databinding: rewrite in kotlin

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

ui/src/main/java/com/wireguard/android/databinding/BindingAdapters.java

@@ -1,150 +0,0 @@
-/*
- * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package com.wireguard.android.databinding;
-
-import android.text.InputFilter;
-import android.view.LayoutInflater;
-import android.widget.LinearLayout;
-import android.widget.TextView;
-
-import com.wireguard.android.BR;
-import com.wireguard.android.R;
-import com.wireguard.android.databinding.ObservableKeyedRecyclerViewAdapter.RowConfigurationHandler;
-import com.wireguard.android.util.ObservableKeyedList;
-import com.wireguard.android.widget.ToggleSwitch;
-import com.wireguard.android.widget.ToggleSwitch.OnBeforeCheckedChangeListener;
-import com.wireguard.config.Attribute;
-import com.wireguard.config.InetNetwork;
-import com.wireguard.util.Keyed;
-import com.wireguard.util.NonNullForAll;
-
-import androidx.annotation.Nullable;
-import androidx.databinding.BindingAdapter;
-import androidx.databinding.DataBindingUtil;
-import androidx.databinding.ObservableList;
-import androidx.databinding.ViewDataBinding;
-import androidx.databinding.adapters.ListenerUtil;
-import androidx.recyclerview.widget.LinearLayoutManager;
-import androidx.recyclerview.widget.RecyclerView;
-import java9.util.Optional;
-
-/**
- * Static methods for use by generated code in the Android data binding library.
- */
-
-@SuppressWarnings("unused")
-@NonNullForAll
-public final class BindingAdapters {
-    private BindingAdapters() {
-        // Prevent instantiation.
-    }
-
-    @BindingAdapter("checked")
-    public static void setChecked(final ToggleSwitch view, final boolean checked) {
-        view.setCheckedInternal(checked);
-    }
-
-    @BindingAdapter("filter")
-    public static void setFilter(final TextView view, final InputFilter filter) {
-        view.setFilters(new InputFilter[]{filter});
-    }
-
-    @BindingAdapter({"items", "layout"})
-    public static <E>
-    void setItems(final LinearLayout view,
-                  @Nullable final ObservableList<E> oldList, final int oldLayoutId,
-                  @Nullable final ObservableList<E> newList, final int newLayoutId) {
-        if (oldList == newList && oldLayoutId == newLayoutId)
-            return;
-        ItemChangeListener<E> listener = ListenerUtil.getListener(view, R.id.item_change_listener);
-        // If the layout changes, any existing listener must be replaced.
-        if (listener != null && oldList != null && oldLayoutId != newLayoutId) {
-            listener.setList(null);
-            listener = null;
-            // Stop tracking the old listener.
-            ListenerUtil.trackListener(view, null, R.id.item_change_listener);
-        }
-        // Avoid adding a listener when there is no new list or layout.
-        if (newList == null || newLayoutId == 0)
-            return;
-        if (listener == null) {
-            listener = new ItemChangeListener<>(view, newLayoutId);
-            ListenerUtil.trackListener(view, listener, R.id.item_change_listener);
-        }
-        // Either the list changed, or this is an entirely new listener because the layout changed.
-        listener.setList(newList);
-    }
-
-    @BindingAdapter({"items", "layout"})
-    public static <E>
-    void setItems(final LinearLayout view,
-                  @Nullable final Iterable<E> oldList, final int oldLayoutId,
-                  @Nullable final Iterable<E> newList, final int newLayoutId) {
-        if (oldList == newList && oldLayoutId == newLayoutId)
-            return;
-        view.removeAllViews();
-        if (newList == null)
-            return;
-        final LayoutInflater layoutInflater = LayoutInflater.from(view.getContext());
-        for (final E item : newList) {
-            final ViewDataBinding binding =
-                    DataBindingUtil.inflate(layoutInflater, newLayoutId, view, false);
-            binding.setVariable(BR.collection, newList);
-            binding.setVariable(BR.item, item);
-            binding.executePendingBindings();
-            view.addView(binding.getRoot());
-        }
-    }
-
-    @BindingAdapter(requireAll = false, value = {"items", "layout", "configurationHandler"})
-    public static <K, E extends Keyed<? extends K>>
-    void setItems(final RecyclerView view,
-                  @Nullable final ObservableKeyedList<K, E> oldList, final int oldLayoutId,
-                  final RowConfigurationHandler oldRowConfigurationHandler,
-                  @Nullable final ObservableKeyedList<K, E> newList, final int newLayoutId,
-                  final RowConfigurationHandler newRowConfigurationHandler) {
-        if (view.getLayoutManager() == null)
-            view.setLayoutManager(new LinearLayoutManager(view.getContext(), RecyclerView.VERTICAL, false));
-
-        if (oldList == newList && oldLayoutId == newLayoutId)
-            return;
-        // The ListAdapter interface is not generic, so this cannot be checked.
-        @SuppressWarnings("unchecked") ObservableKeyedRecyclerViewAdapter<K, E> adapter =
-                (ObservableKeyedRecyclerViewAdapter<K, E>) view.getAdapter();
-        // If the layout changes, any existing adapter must be replaced.
-        if (adapter != null && oldList != null && oldLayoutId != newLayoutId) {
-            adapter.setList(null);
-            adapter = null;
-        }
-        // Avoid setting an adapter when there is no new list or layout.
-        if (newList == null || newLayoutId == 0)
-            return;
-        if (adapter == null) {
-            adapter = new ObservableKeyedRecyclerViewAdapter<>(view.getContext(), newLayoutId, newList);
-            view.setAdapter(adapter);
-        }
-
-        adapter.setRowConfigurationHandler(newRowConfigurationHandler);
-        // Either the list changed, or this is an entirely new listener because the layout changed.
-        adapter.setList(newList);
-    }
-
-    @BindingAdapter("onBeforeCheckedChanged")
-    public static void setOnBeforeCheckedChanged(final ToggleSwitch view,
-                                                 final OnBeforeCheckedChangeListener listener) {
-        view.setOnBeforeCheckedChangeListener(listener);
-    }
-
-    @BindingAdapter("android:text")
-    public static void setText(final TextView view, final Optional<?> text) {
-        view.setText(text.map(Object::toString).orElse(""));
-    }
-
-    @BindingAdapter("android:text")
-    public static void setText(final TextView view, @Nullable final Iterable<InetNetwork> networks) {
-        view.setText(networks != null ? Attribute.join(networks) : "");
-    }
-}

ui/src/main/java/com/wireguard/android/databinding/BindingAdapters.kt

@@ -0,0 +1,137 @@
+/*
+ * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package com.wireguard.android.databinding
+
+import android.text.InputFilter
+import android.view.LayoutInflater
+import android.widget.LinearLayout
+import android.widget.TextView
+import androidx.databinding.BindingAdapter
+import androidx.databinding.DataBindingUtil
+import androidx.databinding.ObservableList
+import androidx.databinding.ViewDataBinding
+import androidx.databinding.adapters.ListenerUtil
+import androidx.recyclerview.widget.LinearLayoutManager
+import androidx.recyclerview.widget.RecyclerView
+import com.wireguard.android.BR
+import com.wireguard.android.R
+import com.wireguard.android.databinding.ObservableKeyedRecyclerViewAdapter.RowConfigurationHandler
+import com.wireguard.android.widget.ToggleSwitch
+import com.wireguard.android.widget.ToggleSwitch.OnBeforeCheckedChangeListener
+import com.wireguard.config.Attribute
+import com.wireguard.config.InetNetwork
+import java9.util.Optional
+
+/**
+ * Static methods for use by generated code in the Android data binding library.
+ */
+object BindingAdapters {
+    @JvmStatic
+    @BindingAdapter("checked")
+    fun setChecked(view: ToggleSwitch, checked: Boolean) {
+        view.setCheckedInternal(checked)
+    }
+
+    @JvmStatic
+    @BindingAdapter("filter")
+    fun setFilter(view: TextView, filter: InputFilter) {
+        view.filters = arrayOf(filter)
+    }
+
+    @JvmStatic
+    @BindingAdapter("items", "layout")
+    fun <E> setItems(view: LinearLayout,
+                     oldList: ObservableList<E>?, oldLayoutId: Int,
+                     newList: ObservableList<E>?, newLayoutId: Int) {
+        if (oldList === newList && oldLayoutId == newLayoutId)
+            return
+        var listener: ItemChangeListener<E>? = ListenerUtil.getListener(view, R.id.item_change_listener)
+        // If the layout changes, any existing listener must be replaced.
+        if (listener != null && oldList != null && oldLayoutId != newLayoutId) {
+            listener.setList(null)
+            listener = null
+            // Stop tracking the old listener.
+            ListenerUtil.trackListener<Any?>(view, null, R.id.item_change_listener)
+        }
+        // Avoid adding a listener when there is no new list or layout.
+        if (newList == null || newLayoutId == 0)
+            return
+        if (listener == null) {
+            listener = ItemChangeListener(view, newLayoutId)
+            ListenerUtil.trackListener(view, listener, R.id.item_change_listener)
+        }
+        // Either the list changed, or this is an entirely new listener because the layout changed.
+        listener.setList(newList)
+    }
+
+    @JvmStatic
+    @BindingAdapter("items", "layout")
+    fun <E> setItems(view: LinearLayout,
+                     oldList: Iterable<E>?, oldLayoutId: Int,
+                     newList: Iterable<E>?, newLayoutId: Int) {
+        if (oldList === newList && oldLayoutId == newLayoutId)
+            return
+        view.removeAllViews()
+        if (newList == null)
+            return
+        val layoutInflater = LayoutInflater.from(view.context)
+        for (item in newList) {
+            val binding = DataBindingUtil.inflate<ViewDataBinding>(layoutInflater, newLayoutId, view, false)
+            binding.setVariable(BR.collection, newList)
+            binding.setVariable(BR.item, item)
+            binding.executePendingBindings()
+            view.addView(binding.root)
+        }
+    }
+
+    @JvmStatic
+    @BindingAdapter(requireAll = false, value = ["items", "layout", "configurationHandler"])
+    fun <K, E : Keyed<out K>> setItems(view: RecyclerView,
+                                       oldList: ObservableKeyedArrayList<K, E>?, oldLayoutId: Int,
+                                       oldRowConfigurationHandler: RowConfigurationHandler<*, *>?,
+                                       newList: ObservableKeyedArrayList<K, E>?, newLayoutId: Int,
+                                       newRowConfigurationHandler: RowConfigurationHandler<*, *>?) {
+        if (view.layoutManager == null)
+            view.layoutManager = LinearLayoutManager(view.context, RecyclerView.VERTICAL, false)
+        if (oldList === newList && oldLayoutId == newLayoutId)
+            return
+        // The ListAdapter interface is not generic, so this cannot be checked.
+        var adapter = view.adapter as ObservableKeyedRecyclerViewAdapter<K, E>?
+        // If the layout changes, any existing adapter must be replaced.
+        if (adapter != null && oldList != null && oldLayoutId != newLayoutId) {
+            adapter.setList(null)
+            adapter = null
+        }
+        // Avoid setting an adapter when there is no new list or layout.
+        if (newList == null || newLayoutId == 0)
+            return
+        if (adapter == null) {
+            adapter = ObservableKeyedRecyclerViewAdapter(view.context, newLayoutId, newList)
+            view.adapter = adapter
+        }
+        adapter.setRowConfigurationHandler(newRowConfigurationHandler)
+        // Either the list changed, or this is an entirely new listener because the layout changed.
+        adapter.setList(newList)
+    }
+
+    @JvmStatic
+    @BindingAdapter("onBeforeCheckedChanged")
+    fun setOnBeforeCheckedChanged(view: ToggleSwitch,
+                                  listener: OnBeforeCheckedChangeListener?) {
+        view.setOnBeforeCheckedChangeListener(listener)
+    }
+
+    @JvmStatic
+    @BindingAdapter("android:text")
+    fun setText(view: TextView, text: Optional<*>) {
+        view.text = text.map { obj: Any -> obj.toString() }.orElse("")
+    }
+
+    @JvmStatic
+    @BindingAdapter("android:text")
+    fun setText(view: TextView, networks: Iterable<InetNetwork?>?) {
+        view.text = if (networks != null) Attribute.join(networks) else ""
+    }
+}

ui/src/main/java/com/wireguard/android/databinding/ItemChangeListener.java

@@ -1,143 +0,0 @@
-/*
- * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package com.wireguard.android.databinding;
-
-import android.view.LayoutInflater;
-import android.view.View;
-import android.view.ViewGroup;
-
-import com.wireguard.android.BR;
-import com.wireguard.util.NonNullForAll;
-
-import java.lang.ref.WeakReference;
-import java.util.Objects;
-
-import androidx.annotation.Nullable;
-import androidx.databinding.DataBindingUtil;
-import androidx.databinding.ObservableList;
-import androidx.databinding.ViewDataBinding;
-
-/**
- * Helper class for binding an ObservableList to the children of a ViewGroup.
- */
-
-@NonNullForAll
-class ItemChangeListener<T> {
-    private final OnListChangedCallback<T> callback = new OnListChangedCallback<>(this);
-    private final ViewGroup container;
-    private final int layoutId;
-    private final LayoutInflater layoutInflater;
-    @Nullable private ObservableList<T> list;
-
-    ItemChangeListener(final ViewGroup container, final int layoutId) {
-        this.container = container;
-        this.layoutId = layoutId;
-        layoutInflater = LayoutInflater.from(container.getContext());
-    }
-
-    private View getView(final int position, @Nullable final View convertView) {
-        ViewDataBinding binding = convertView != null ? DataBindingUtil.getBinding(convertView) : null;
-        if (binding == null) {
-            binding = DataBindingUtil.inflate(layoutInflater, layoutId, container, false);
-        }
-
-        Objects.requireNonNull(list, "Trying to get a view while list is still null");
-
-        binding.setVariable(BR.collection, list);
-        binding.setVariable(BR.item, list.get(position));
-        binding.executePendingBindings();
-        return binding.getRoot();
-    }
-
-    void setList(@Nullable final ObservableList<T> newList) {
-        if (list != null)
-            list.removeOnListChangedCallback(callback);
-        list = newList;
-        if (list != null) {
-            list.addOnListChangedCallback(callback);
-            callback.onChanged(list);
-        } else {
-            container.removeAllViews();
-        }
-    }
-
-    private static final class OnListChangedCallback<T>
-            extends ObservableList.OnListChangedCallback<ObservableList<T>> {
-
-        private final WeakReference<ItemChangeListener<T>> weakListener;
-
-        private OnListChangedCallback(final ItemChangeListener<T> listener) {
-            weakListener = new WeakReference<>(listener);
-        }
-
-        @Override
-        public void onChanged(final ObservableList<T> sender) {
-            final ItemChangeListener<T> listener = weakListener.get();
-            if (listener != null) {
-                // TODO: recycle views
-                listener.container.removeAllViews();
-                for (int i = 0; i < sender.size(); ++i)
-                    listener.container.addView(listener.getView(i, null));
-            } else {
-                sender.removeOnListChangedCallback(this);
-            }
-        }
-
-        @Override
-        public void onItemRangeChanged(final ObservableList<T> sender, final int positionStart,
-                                       final int itemCount) {
-            final ItemChangeListener<T> listener = weakListener.get();
-            if (listener != null) {
-                for (int i = positionStart; i < positionStart + itemCount; ++i) {
-                    final View child = listener.container.getChildAt(i);
-                    listener.container.removeViewAt(i);
-                    listener.container.addView(listener.getView(i, child));
-                }
-            } else {
-                sender.removeOnListChangedCallback(this);
-            }
-        }
-
-        @Override
-        public void onItemRangeInserted(final ObservableList<T> sender, final int positionStart,
-                                        final int itemCount) {
-            final ItemChangeListener<T> listener = weakListener.get();
-            if (listener != null) {
-                for (int i = positionStart; i < positionStart + itemCount; ++i)
-                    listener.container.addView(listener.getView(i, null));
-            } else {
-                sender.removeOnListChangedCallback(this);
-            }
-        }
-
-        @Override
-        public void onItemRangeMoved(final ObservableList<T> sender, final int fromPosition,
-                                     final int toPosition, final int itemCount) {
-            final ItemChangeListener<T> listener = weakListener.get();
-            if (listener != null) {
-                final View[] views = new View[itemCount];
-                for (int i = 0; i < itemCount; ++i)
-                    views[i] = listener.container.getChildAt(fromPosition + i);
-                listener.container.removeViews(fromPosition, itemCount);
-                for (int i = 0; i < itemCount; ++i)
-                    listener.container.addView(views[i], toPosition + i);
-            } else {
-                sender.removeOnListChangedCallback(this);
-            }
-        }
-
-        @Override
-        public void onItemRangeRemoved(final ObservableList<T> sender, final int positionStart,
-                                       final int itemCount) {
-            final ItemChangeListener<T> listener = weakListener.get();
-            if (listener != null) {
-                listener.container.removeViews(positionStart, itemCount);
-            } else {
-                sender.removeOnListChangedCallback(this);
-            }
-        }
-    }
-}

ui/src/main/java/com/wireguard/android/databinding/ItemChangeListener.kt

@@ -0,0 +1,112 @@
+/*
+ * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package com.wireguard.android.databinding
+
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.databinding.DataBindingUtil
+import androidx.databinding.ObservableList
+import androidx.databinding.ViewDataBinding
+import com.wireguard.android.BR
+import java.lang.ref.WeakReference
+
+/**
+ * Helper class for binding an ObservableList to the children of a ViewGroup.
+ */
+internal class ItemChangeListener<T>(private val container: ViewGroup, private val layoutId: Int) {
+    private val callback = OnListChangedCallback(this)
+    private val layoutInflater: LayoutInflater = LayoutInflater.from(container.context)
+    private var list: ObservableList<T>? = null
+
+    private fun getView(position: Int, convertView: View?): View {
+        var binding = if (convertView != null) DataBindingUtil.getBinding<ViewDataBinding>(convertView) else null
+        if (binding == null) {
+            binding = DataBindingUtil.inflate(layoutInflater, layoutId, container, false)
+        }
+        require(list != null) { "Trying to get a view while list is still null" }
+        binding!!.setVariable(BR.collection, list)
+        binding.setVariable(BR.item, list!![position])
+        binding.executePendingBindings()
+        return binding.root
+    }
+
+    fun setList(newList: ObservableList<T>?) {
+        list?.removeOnListChangedCallback(callback)
+        list = newList
+        if (list != null) {
+            list!!.addOnListChangedCallback(callback)
+            callback.onChanged(list!!)
+        } else {
+            container.removeAllViews()
+        }
+    }
+
+    private class OnListChangedCallback<T> constructor(listener: ItemChangeListener<T>) : ObservableList.OnListChangedCallback<ObservableList<T>>() {
+        private val weakListener: WeakReference<ItemChangeListener<T>> = WeakReference(listener)
+
+        override fun onChanged(sender: ObservableList<T>) {
+            val listener = weakListener.get()
+            if (listener != null) {
+                // TODO: recycle views
+                listener.container.removeAllViews()
+                for (i in sender.indices)
+                    listener.container.addView(listener.getView(i, null))
+            } else {
+                sender.removeOnListChangedCallback(this)
+            }
+        }
+
+        override fun onItemRangeChanged(sender: ObservableList<T>, positionStart: Int,
+                                        itemCount: Int) {
+            val listener = weakListener.get()
+            if (listener != null) {
+                for (i in positionStart until positionStart + itemCount) {
+                    val child = listener.container.getChildAt(i)
+                    listener.container.removeViewAt(i)
+                    listener.container.addView(listener.getView(i, child))
+                }
+            } else {
+                sender.removeOnListChangedCallback(this)
+            }
+        }
+
+        override fun onItemRangeInserted(sender: ObservableList<T>, positionStart: Int,
+                                         itemCount: Int) {
+            val listener = weakListener.get()
+            if (listener != null) {
+                for (i in positionStart until positionStart + itemCount)
+                    listener.container.addView(listener.getView(i, null))
+            } else {
+                sender.removeOnListChangedCallback(this)
+            }
+        }
+
+        override fun onItemRangeMoved(sender: ObservableList<T>, fromPosition: Int,
+                                      toPosition: Int, itemCount: Int) {
+            val listener = weakListener.get()
+            if (listener != null) {
+                val views = arrayOfNulls<View>(itemCount)
+                for (i in 0 until itemCount) views[i] = listener.container.getChildAt(fromPosition + i)
+                listener.container.removeViews(fromPosition, itemCount)
+                for (i in 0 until itemCount) listener.container.addView(views[i], toPosition + i)
+            } else {
+                sender.removeOnListChangedCallback(this)
+            }
+        }
+
+        override fun onItemRangeRemoved(sender: ObservableList<T>, positionStart: Int,
+                                        itemCount: Int) {
+            val listener = weakListener.get()
+            if (listener != null) {
+                listener.container.removeViews(positionStart, itemCount)
+            } else {
+                sender.removeOnListChangedCallback(this)
+            }
+        }
+
+    }
+
+}

ui/src/main/java/com/wireguard/android/databinding/Keyed.kt

@@ -0,0 +1,12 @@
+/*
+ * Copyright © 2020 WireGuard LLC. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package com.wireguard.android.databinding
+
+/**
+ * Interface for objects that have a identifying key of the given type.
+ */
+interface Keyed<K> {
+    val key: K
+}

ui/src/main/java/com/wireguard/android/databinding/ObservableKeyedArrayList.kt

@@ -0,0 +1,32 @@
+/*
+ * Copyright © 2020 WireGuard LLC. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package com.wireguard.android.databinding
+
+import androidx.databinding.ObservableArrayList
+
+/**
+ * ArrayList that allows looking up elements by some key property. As the key property must always
+ * be retrievable, this list cannot hold `null` elements. Because this class places no
+ * restrictions on the order or duplication of keys, lookup by key, as well as all list modification
+ * operations, require O(n) time.
+ */
+open class ObservableKeyedArrayList<K, E : Keyed<out K>> : ObservableArrayList<E>() {
+    fun containsKey(key: K) = indexOfKey(key) >= 0
+
+    operator fun get(key: K): E? {
+        val index = indexOfKey(key)
+        return if (index >= 0) get(index) else null
+    }
+
+    open fun indexOfKey(key: K): Int {
+        val iterator = listIterator()
+        while (iterator.hasNext()) {
+            val index = iterator.nextIndex()
+            if (iterator.next()!!.key == key)
+                return index
+        }
+        return -1
+    }
+}

ui/src/main/java/com/wireguard/android/databinding/ObservableKeyedRecyclerViewAdapter.java

@@ -1,162 +0,0 @@
-/*
- * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package com.wireguard.android.databinding;
-
-import android.content.Context;
-import android.view.LayoutInflater;
-import android.view.ViewGroup;
-
-import com.wireguard.android.BR;
-import com.wireguard.android.util.ObservableKeyedList;
-import com.wireguard.util.Keyed;
-import com.wireguard.util.NonNullForAll;
-
-import java.lang.ref.WeakReference;
-
-import androidx.annotation.Nullable;
-import androidx.databinding.DataBindingUtil;
-import androidx.databinding.ObservableList;
-import androidx.databinding.ViewDataBinding;
-import androidx.recyclerview.widget.RecyclerView;
-import androidx.recyclerview.widget.RecyclerView.Adapter;
-
-/**
- * A generic {@code RecyclerView.Adapter} backed by a {@code ObservableKeyedList}.
- */
-
-@NonNullForAll
-public class ObservableKeyedRecyclerViewAdapter<K, E extends Keyed<? extends K>> extends Adapter<ObservableKeyedRecyclerViewAdapter.ViewHolder> {
-
-    private final OnListChangedCallback<E> callback = new OnListChangedCallback<>(this);
-    private final int layoutId;
-    private final LayoutInflater layoutInflater;
-    @Nullable private ObservableKeyedList<K, E> list;
-    @Nullable private RowConfigurationHandler rowConfigurationHandler;
-
-    ObservableKeyedRecyclerViewAdapter(final Context context, final int layoutId,
-                                       final ObservableKeyedList<K, E> list) {
-        this.layoutId = layoutId;
-        layoutInflater = LayoutInflater.from(context);
-        setList(list);
-    }
-
-    @Nullable
-    private E getItem(final int position) {
-        if (list == null || position < 0 || position >= list.size())
-            return null;
-        return list.get(position);
-    }
-
-    @Override
-    public int getItemCount() {
-        return list != null ? list.size() : 0;
-    }
-
-    @Override
-    public long getItemId(final int position) {
-        final K key = getKey(position);
-        return key != null ? key.hashCode() : -1;
-    }
-
-    @Nullable
-    private K getKey(final int position) {
-        final E item = getItem(position);
-        return item != null ? item.getKey() : null;
-    }
-
-    @SuppressWarnings("unchecked")
-    @Override
-    public void onBindViewHolder(final ViewHolder holder, final int position) {
-        holder.binding.setVariable(BR.collection, list);
-        holder.binding.setVariable(BR.key, getKey(position));
-        holder.binding.setVariable(BR.item, getItem(position));
-        holder.binding.executePendingBindings();
-
-        if (rowConfigurationHandler != null) {
-            final E item = getItem(position);
-            if (item != null) {
-                rowConfigurationHandler.onConfigureRow(holder.binding, item, position);
-            }
-        }
-    }
-
-    @Override
-    public ViewHolder onCreateViewHolder(final ViewGroup parent, final int viewType) {
-        return new ViewHolder(DataBindingUtil.inflate(layoutInflater, layoutId, parent, false));
-    }
-
-    void setList(@Nullable final ObservableKeyedList<K, E> newList) {
-        if (list != null)
-            list.removeOnListChangedCallback(callback);
-        list = newList;
-        if (list != null) {
-            list.addOnListChangedCallback(callback);
-        }
-        notifyDataSetChanged();
-    }
-
-    void setRowConfigurationHandler(final RowConfigurationHandler rowConfigurationHandler) {
-        this.rowConfigurationHandler = rowConfigurationHandler;
-    }
-
-    public interface RowConfigurationHandler<B extends ViewDataBinding, T> {
-        void onConfigureRow(B binding, T item, int position);
-    }
-
-    private static final class OnListChangedCallback<E extends Keyed<?>>
-            extends ObservableList.OnListChangedCallback<ObservableList<E>> {
-
-        private final WeakReference<ObservableKeyedRecyclerViewAdapter<?, E>> weakAdapter;
-
-        private OnListChangedCallback(final ObservableKeyedRecyclerViewAdapter<?, E> adapter) {
-            weakAdapter = new WeakReference<>(adapter);
-        }
-
-        @Override
-        public void onChanged(final ObservableList<E> sender) {
-            final ObservableKeyedRecyclerViewAdapter adapter = weakAdapter.get();
-            if (adapter != null)
-                adapter.notifyDataSetChanged();
-            else
-                sender.removeOnListChangedCallback(this);
-        }
-
-        @Override
-        public void onItemRangeChanged(final ObservableList<E> sender, final int positionStart,
-                                       final int itemCount) {
-            onChanged(sender);
-        }
-
-        @Override
-        public void onItemRangeInserted(final ObservableList<E> sender, final int positionStart,
-                                        final int itemCount) {
-            onChanged(sender);
-        }
-
-        @Override
-        public void onItemRangeMoved(final ObservableList<E> sender, final int fromPosition,
-                                     final int toPosition, final int itemCount) {
-            onChanged(sender);
-        }
-
-        @Override
-        public void onItemRangeRemoved(final ObservableList<E> sender, final int positionStart,
-                                       final int itemCount) {
-            onChanged(sender);
-        }
-    }
-
-    public static class ViewHolder extends RecyclerView.ViewHolder {
-        final ViewDataBinding binding;
-
-        public ViewHolder(final ViewDataBinding binding) {
-            super(binding.getRoot());
-
-            this.binding = binding;
-        }
-    }
-
-}

ui/src/main/java/com/wireguard/android/databinding/ObservableKeyedRecyclerViewAdapter.kt

@@ -0,0 +1,103 @@
+/*
+ * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package com.wireguard.android.databinding
+
+import android.content.Context
+import android.view.LayoutInflater
+import android.view.ViewGroup
+import androidx.databinding.DataBindingUtil
+import androidx.databinding.ObservableList
+import androidx.databinding.ViewDataBinding
+import androidx.recyclerview.widget.RecyclerView
+import com.wireguard.android.BR
+import java.lang.ref.WeakReference
+
+/**
+ * A generic `RecyclerView.Adapter` backed by a `ObservableKeyedArrayList`.
+ */
+class ObservableKeyedRecyclerViewAdapter<K, E : Keyed<out K>> internal constructor(context: Context, private val layoutId: Int,
+                                                                                   list: ObservableKeyedArrayList<K, E>?) : RecyclerView.Adapter<ObservableKeyedRecyclerViewAdapter.ViewHolder>() {
+    private val callback = OnListChangedCallback(this)
+    private val layoutInflater: LayoutInflater = LayoutInflater.from(context)
+    private var list: ObservableKeyedArrayList<K, E>? = null
+    private var rowConfigurationHandler: RowConfigurationHandler<ViewDataBinding, Any>? = null
+
+    private fun getItem(position: Int): E? = if (list == null || position < 0 || position >= list!!.size) null else list?.get(position)
+
+    override fun getItemCount() = list?.size ?: 0
+
+    override fun getItemId(position: Int) = (getKey(position)?.hashCode() ?: -1).toLong()
+
+    private fun getKey(position: Int): K? = getItem(position)?.key
+
+    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
+        holder.binding.setVariable(BR.collection, list)
+        holder.binding.setVariable(BR.key, getKey(position))
+        holder.binding.setVariable(BR.item, getItem(position))
+        holder.binding.executePendingBindings()
+        if (rowConfigurationHandler != null) {
+            val item = getItem(position)
+            if (item != null) {
+                rowConfigurationHandler?.onConfigureRow(holder.binding, item, position)
+            }
+        }
+    }
+
+    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int) = ViewHolder(DataBindingUtil.inflate(layoutInflater, layoutId, parent, false))
+
+    fun setList(newList: ObservableKeyedArrayList<K, E>?) {
+        list?.removeOnListChangedCallback(callback)
+        list = newList
+        list?.addOnListChangedCallback(callback)
+        notifyDataSetChanged()
+    }
+
+    fun setRowConfigurationHandler(rowConfigurationHandler: RowConfigurationHandler<*, *>?) {
+        this.rowConfigurationHandler = rowConfigurationHandler as? RowConfigurationHandler<ViewDataBinding, Any>
+    }
+
+    interface RowConfigurationHandler<B : ViewDataBinding, T> {
+        fun onConfigureRow(binding: B, item: T, position: Int)
+    }
+
+    private class OnListChangedCallback<E : Keyed<*>> constructor(adapter: ObservableKeyedRecyclerViewAdapter<*, E>) : ObservableList.OnListChangedCallback<ObservableList<E>>() {
+        private val weakAdapter: WeakReference<ObservableKeyedRecyclerViewAdapter<*, E>> = WeakReference(adapter)
+
+        override fun onChanged(sender: ObservableList<E>) {
+            val adapter = weakAdapter.get()
+            if (adapter != null)
+                adapter.notifyDataSetChanged()
+            else
+                sender.removeOnListChangedCallback(this)
+        }
+
+        override fun onItemRangeChanged(sender: ObservableList<E>, positionStart: Int,
+                                        itemCount: Int) {
+            onChanged(sender)
+        }
+
+        override fun onItemRangeInserted(sender: ObservableList<E>, positionStart: Int,
+                                         itemCount: Int) {
+            onChanged(sender)
+        }
+
+        override fun onItemRangeMoved(sender: ObservableList<E>, fromPosition: Int,
+                                      toPosition: Int, itemCount: Int) {
+            onChanged(sender)
+        }
+
+        override fun onItemRangeRemoved(sender: ObservableList<E>, positionStart: Int,
+                                        itemCount: Int) {
+            onChanged(sender)
+        }
+
+    }
+
+    class ViewHolder(val binding: ViewDataBinding) : RecyclerView.ViewHolder(binding.root)
+
+    init {
+        setList(list)
+    }
+}

ui/src/main/java/com/wireguard/android/databinding/ObservableSortedKeyedArrayList.kt

@@ -0,0 +1,106 @@
+/*
+ * Copyright © 2020 WireGuard LLC. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package com.wireguard.android.databinding
+
+import java.util.AbstractList
+import java.util.Collections
+import java.util.Comparator
+import java.util.NoSuchElementException
+import java.util.Spliterator
+
+/**
+ * KeyedArrayList that enforces uniqueness and sorted order across the set of keys. This class uses
+ * binary search to improve lookup and replacement times to O(log(n)). However, due to the
+ * array-based nature of this class, insertion and removal of elements with anything but the largest
+ * key still require O(n) time.
+ */
+class ObservableSortedKeyedArrayList<K, E : Keyed<out K>>(private val comparator: Comparator<in K>?) : ObservableKeyedArrayList<K, E>() {
+    @Transient
+    private val keyList = KeyList(this)
+
+    override fun add(element: E): Boolean {
+        val insertionPoint = getInsertionPoint(element)
+        if (insertionPoint < 0) {
+            // Skipping insertion is non-destructive if the new and existing objects are the same.
+            if (element === get(-insertionPoint - 1)) return false
+            throw IllegalArgumentException("Element with same key already exists in list")
+        }
+        super.add(insertionPoint, element)
+        return true
+    }
+
+    override fun add(index: Int, element: E) {
+        val insertionPoint = getInsertionPoint(element)
+        require(insertionPoint >= 0) { "Element with same key already exists in list" }
+        if (insertionPoint != index) throw IndexOutOfBoundsException("Wrong index given for element")
+        super.add(index, element)
+    }
+
+    override fun addAll(elements: Collection<E>): Boolean {
+        var didChange = false
+        for (e in elements) {
+            if (add(e))
+                didChange = true
+        }
+        return didChange
+    }
+
+    override fun addAll(index: Int, elements: Collection<E>): Boolean {
+        var i = index
+        for (e in elements)
+            add(i++, e)
+        return true
+    }
+
+    private fun getInsertionPoint(e: E): Int {
+        return if (comparator != null) {
+            -Collections.binarySearch(keyList, e.key, comparator) - 1
+        } else {
+            val list = keyList as List<Comparable<K>>
+            -Collections.binarySearch(list, e.key) - 1
+        }
+    }
+
+    override fun indexOfKey(key: K): Int {
+        val index: Int
+        index = if (comparator != null) {
+            Collections.binarySearch(keyList, key, comparator)
+        } else {
+            val list = keyList as List<Comparable<K>>
+            Collections.binarySearch(list, key)
+        }
+        return if (index >= 0) index else -1
+    }
+
+    override fun set(index: Int, element: E): E {
+        val order: Int
+        order = if (comparator != null) {
+            comparator.compare(element.key, get(index).key)
+        } else {
+            val key = element.key as Comparable<K>
+            key.compareTo(get(index).key)
+        }
+        if (order != 0) {
+            // Allow replacement if the new key would be inserted adjacent to the replaced element.
+            val insertionPoint = getInsertionPoint(element)
+            if (insertionPoint < index || insertionPoint > index + 1)
+                throw IndexOutOfBoundsException("Wrong index given for element")
+        }
+        return super.set(index, element)
+    }
+
+    fun values(): Collection<E> {
+        return this
+    }
+
+    private class KeyList<K, E : Keyed<out K>>(private val list: ObservableSortedKeyedArrayList<K, E>) : AbstractList<K>(), Set<K> {
+        override fun get(index: Int): K = list[index].key
+
+        override val size
+            get() = list.size
+
+        override fun spliterator(): Spliterator<K> = super<AbstractList>.spliterator()
+    }
+}

ui/src/main/java/com/wireguard/android/fragment/AppListDialogFragment.kt

@@ -17,11 +17,10 @@ import com.wireguard.android.R
 import com.wireguard.android.databinding.AppListDialogFragmentBinding
 import com.wireguard.android.model.ApplicationData
 import com.wireguard.android.util.ErrorMessages
-import com.wireguard.android.util.ObservableKeyedArrayList
+import com.wireguard.android.databinding.ObservableKeyedArrayList
-import com.wireguard.android.util.ObservableKeyedList
 
 class AppListDialogFragment : DialogFragment() {
-    private val appData: ObservableKeyedList<String, ApplicationData> = ObservableKeyedArrayList()
+    private val appData: ObservableKeyedArrayList<String, ApplicationData> = ObservableKeyedArrayList()
     private var currentlyExcludedApps = emptyList<String>()
 
     private fun loadData() {

ui/src/main/java/com/wireguard/android/fragment/TunnelListFragment.kt

@@ -267,11 +267,13 @@ class TunnelListFragment : BaseFragment() {
         binding ?: return
         binding!!.fragment = this
         Application.getTunnelManager().tunnels.thenAccept { tunnels -> binding!!.tunnels = tunnels }
-        binding!!.rowConfigurationHandler = RowConfigurationHandler { binding: TunnelListItemBinding, tunnel: ObservableTunnel, position ->
+        val parent = this
-            binding.fragment = this
+        binding!!.rowConfigurationHandler = object : RowConfigurationHandler<TunnelListItemBinding, ObservableTunnel> {
+            override fun onConfigureRow(binding: TunnelListItemBinding, item: ObservableTunnel, position: Int) {
+                binding.fragment = parent
                 binding.root.setOnClickListener {
                     if (actionMode == null) {
-                    selectedTunnel = tunnel
+                        selectedTunnel = item
                     } else {
                         actionModeListener.toggleItemChecked(position)
                     }
@@ -283,7 +285,8 @@ class TunnelListFragment : BaseFragment() {
                 if (actionMode != null)
                     (binding.root as MultiselectableRelativeLayout).setMultiSelected(actionModeListener.checkedItems.contains(position))
                 else
-                (binding.root as MultiselectableRelativeLayout).setSingleSelected(selectedTunnel == tunnel)
+                    (binding.root as MultiselectableRelativeLayout).setSingleSelected(selectedTunnel == item)
+            }
         }
     }
 

ui/src/main/java/com/wireguard/android/model/ApplicationData.kt

@@ -8,12 +8,10 @@ import android.graphics.drawable.Drawable
 import androidx.databinding.BaseObservable
 import androidx.databinding.Bindable
 import com.wireguard.android.BR
-import com.wireguard.util.Keyed
+import com.wireguard.android.databinding.Keyed
 
 class ApplicationData(val icon: Drawable, val name: String, val packageName: String, isExcludedFromTunnel: Boolean) : BaseObservable(), Keyed<String> {
-    override fun getKey(): String {
+    override val key = name
-        return name
-    }
 
     @get:Bindable
     var isExcludedFromTunnel = isExcludedFromTunnel

ui/src/main/java/com/wireguard/android/model/ObservableTunnel.kt

@@ -11,7 +11,7 @@ import com.wireguard.android.backend.Statistics
 import com.wireguard.android.backend.Tunnel
 import com.wireguard.android.util.ExceptionLoggers
 import com.wireguard.config.Config
-import com.wireguard.util.Keyed
+import com.wireguard.android.databinding.Keyed
 import java9.util.concurrent.CompletableFuture
 import java9.util.concurrent.CompletionStage
 
@@ -24,8 +24,7 @@ class ObservableTunnel internal constructor(
         config: Config?,
         state: Tunnel.State
 ) : BaseObservable(), Keyed<String>, Tunnel {
-    override fun getKey() = name
+    override val key = name
-
 
     @Bindable
     override fun getName() = name

ui/src/main/java/com/wireguard/android/model/TunnelManager.kt

@@ -22,8 +22,7 @@ import com.wireguard.android.backend.Statistics
 import com.wireguard.android.backend.Tunnel
 import com.wireguard.android.configStore.ConfigStore
 import com.wireguard.android.util.ExceptionLoggers
-import com.wireguard.android.util.ObservableSortedKeyedArrayList
+import com.wireguard.android.databinding.ObservableSortedKeyedArrayList
-import com.wireguard.android.util.ObservableSortedKeyedList
 import com.wireguard.config.Config
 import java9.util.Comparators
 import java9.util.concurrent.CompletableFuture
@@ -34,10 +33,10 @@ import java.util.ArrayList
  * Maintains and mediates changes to the set of available WireGuard tunnels,
  */
 class TunnelManager(private val configStore: ConfigStore) : BaseObservable() {
-    val tunnels = CompletableFuture<ObservableSortedKeyedList<String, ObservableTunnel>>()
+    val tunnels = CompletableFuture<ObservableSortedKeyedArrayList<String, ObservableTunnel>>()
     private val context: Context = get()
     private val delayedLoadRestoreTunnels = ArrayList<CompletableFuture<Void>>()
-    private val tunnelMap: ObservableSortedKeyedList<String, ObservableTunnel> = ObservableSortedKeyedArrayList(COMPARATOR)
+    private val tunnelMap: ObservableSortedKeyedArrayList<String, ObservableTunnel> = ObservableSortedKeyedArrayList(COMPARATOR)
     private var haveLoaded = false
 
     private fun addToList(name: String, config: Config?, state: Tunnel.State): ObservableTunnel? {

ui/src/main/java/com/wireguard/android/util/ObservableKeyedArrayList.java

@@ -1,111 +0,0 @@
-/*
- * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package com.wireguard.android.util;
-
-import com.wireguard.util.Keyed;
-import com.wireguard.util.NonNullForAll;
-
-import java.util.Collection;
-import java.util.ListIterator;
-import java.util.Objects;
-
-import androidx.annotation.Nullable;
-import androidx.databinding.ObservableArrayList;
-
-/**
- * ArrayList that allows looking up elements by some key property. As the key property must always
- * be retrievable, this list cannot hold {@code null} elements. Because this class places no
- * restrictions on the order or duplication of keys, lookup by key, as well as all list modification
- * operations, require O(n) time.
- */
-
-@NonNullForAll
-public class ObservableKeyedArrayList<K, E extends Keyed<? extends K>>
-        extends ObservableArrayList<E> implements ObservableKeyedList<K, E> {
-    @Override
-    public boolean add(@Nullable final E e) {
-        if (e == null)
-            throw new NullPointerException("Trying to add a null element");
-        return super.add(e);
-    }
-
-    @Override
-    public void add(final int index, @Nullable final E e) {
-        if (e == null)
-            throw new NullPointerException("Trying to add a null element");
-        super.add(index, e);
-    }
-
-    @Override
-    public boolean addAll(final Collection<? extends E> c) {
-        if (c.contains(null))
-            throw new NullPointerException("Trying to add a collection with null element(s)");
-        return super.addAll(c);
-    }
-
-    @Override
-    public boolean addAll(final int index, final Collection<? extends E> c) {
-        if (c.contains(null))
-            throw new NullPointerException("Trying to add a collection with null element(s)");
-        return super.addAll(index, c);
-    }
-
-    @Override
-    public boolean containsAllKeys(final Collection<K> keys) {
-        for (final K key : keys)
-            if (!containsKey(key))
-                return false;
-        return true;
-    }
-
-    @Override
-    public boolean containsKey(final K key) {
-        return indexOfKey(key) >= 0;
-    }
-
-    @Nullable
-    @Override
-    public E get(final K key) {
-        final int index = indexOfKey(key);
-        return index >= 0 ? get(index) : null;
-    }
-
-    @Nullable
-    @Override
-    public E getLast(final K key) {
-        final int index = lastIndexOfKey(key);
-        return index >= 0 ? get(index) : null;
-    }
-
-    @Override
-    public int indexOfKey(final K key) {
-        final ListIterator<E> iterator = listIterator();
-        while (iterator.hasNext()) {
-            final int index = iterator.nextIndex();
-            if (Objects.equals(iterator.next().getKey(), key))
-                return index;
-        }
-        return -1;
-    }
-
-    @Override
-    public int lastIndexOfKey(final K key) {
-        final ListIterator<E> iterator = listIterator(size());
-        while (iterator.hasPrevious()) {
-            final int index = iterator.previousIndex();
-            if (Objects.equals(iterator.previous().getKey(), key))
-                return index;
-        }
-        return -1;
-    }
-
-    @Override
-    public E set(final int index, @Nullable final E e) {
-        if (e == null)
-            throw new NullPointerException("Trying to set a null key");
-        return super.set(index, e);
-    }
-}

ui/src/main/java/com/wireguard/android/util/ObservableKeyedList.java

@@ -1,21 +0,0 @@
-/*
- * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package com.wireguard.android.util;
-
-import com.wireguard.util.Keyed;
-import com.wireguard.util.KeyedList;
-import com.wireguard.util.NonNullForAll;
-
-import androidx.databinding.ObservableList;
-
-/**
- * A list that is both keyed and observable.
- */
-
-@NonNullForAll
-public interface ObservableKeyedList<K, E extends Keyed<? extends K>>
-        extends KeyedList<K, E>, ObservableList<E> {
-}

ui/src/main/java/com/wireguard/android/util/ObservableSortedKeyedArrayList.java

@@ -1,200 +0,0 @@
-/*
- * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package com.wireguard.android.util;
-
-import com.wireguard.util.Keyed;
-import com.wireguard.util.NonNullForAll;
-import com.wireguard.util.SortedKeyedList;
-
-import java.util.AbstractList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.Comparator;
-import java.util.List;
-import java.util.NoSuchElementException;
-import java.util.Set;
-import java.util.Spliterator;
-
-import androidx.annotation.Nullable;
-
-/**
- * KeyedArrayList that enforces uniqueness and sorted order across the set of keys. This class uses
- * binary search to improve lookup and replacement times to O(log(n)). However, due to the
- * array-based nature of this class, insertion and removal of elements with anything but the largest
- * key still require O(n) time.
- */
-
-@NonNullForAll
-public class ObservableSortedKeyedArrayList<K, E extends Keyed<? extends K>>
-        extends ObservableKeyedArrayList<K, E> implements ObservableSortedKeyedList<K, E> {
-    @Nullable private final Comparator<? super K> comparator;
-    private final transient KeyList<K, E> keyList = new KeyList<>(this);
-
-    @SuppressWarnings("WeakerAccess")
-    public ObservableSortedKeyedArrayList() {
-        comparator = null;
-    }
-
-    public ObservableSortedKeyedArrayList(final Comparator<? super K> comparator) {
-        this.comparator = comparator;
-    }
-
-    public ObservableSortedKeyedArrayList(final Collection<? extends E> c) {
-        this();
-        addAll(c);
-    }
-
-    public ObservableSortedKeyedArrayList(final SortedKeyedList<K, E> other) {
-        this(other.comparator());
-        addAll(other);
-    }
-
-    @Override
-    public boolean add(final E e) {
-        final int insertionPoint = getInsertionPoint(e);
-        if (insertionPoint < 0) {
-            // Skipping insertion is non-destructive if the new and existing objects are the same.
-            if (e == get(-insertionPoint - 1))
-                return false;
-            throw new IllegalArgumentException("Element with same key already exists in list");
-        }
-        super.add(insertionPoint, e);
-        return true;
-    }
-
-    @Override
-    public void add(final int index, final E e) {
-        final int insertionPoint = getInsertionPoint(e);
-        if (insertionPoint < 0)
-            throw new IllegalArgumentException("Element with same key already exists in list");
-        if (insertionPoint != index)
-            throw new IndexOutOfBoundsException("Wrong index given for element");
-        super.add(index, e);
-    }
-
-    @Override
-    public boolean addAll(final Collection<? extends E> c) {
-        boolean didChange = false;
-        for (final E e : c)
-            if (add(e))
-                didChange = true;
-        return didChange;
-    }
-
-    @Override
-    public boolean addAll(int index, final Collection<? extends E> c) {
-        for (final E e : c)
-            add(index++, e);
-        return true;
-    }
-
-    @Nullable
-    @Override
-    public Comparator<? super K> comparator() {
-        return comparator;
-    }
-
-    @Override
-    public K firstKey() {
-        if (isEmpty())
-            // The parameter in the exception is only to shut
-            // lint up, we never care for the exception message.
-            throw new NoSuchElementException("Empty set");
-        return get(0).getKey();
-    }
-
-    private int getInsertionPoint(final E e) {
-        if (comparator != null) {
-            return -Collections.binarySearch(keyList, e.getKey(), comparator) - 1;
-        } else {
-            @SuppressWarnings("unchecked") final List<Comparable<? super K>> list =
-                    (List<Comparable<? super K>>) keyList;
-            return -Collections.binarySearch(list, e.getKey()) - 1;
-        }
-    }
-
-    @Override
-    public int indexOfKey(final K key) {
-        final int index;
-        if (comparator != null) {
-            index = Collections.binarySearch(keyList, key, comparator);
-        } else {
-            @SuppressWarnings("unchecked") final List<Comparable<? super K>> list =
-                    (List<Comparable<? super K>>) keyList;
-            index = Collections.binarySearch(list, key);
-        }
-        return index >= 0 ? index : -1;
-    }
-
-    @Override
-    public Set<K> keySet() {
-        return keyList;
-    }
-
-    @Override
-    public int lastIndexOfKey(final K key) {
-        // There can never be more than one element with the same key in the list.
-        return indexOfKey(key);
-    }
-
-    @Override
-    public K lastKey() {
-        if (isEmpty())
-            // The parameter in the exception is only to shut
-            // lint up, we never care for the exception message.
-            throw new NoSuchElementException("Empty set");
-        return get(size() - 1).getKey();
-    }
-
-    @Override
-    public E set(final int index, final E e) {
-        final int order;
-        if (comparator != null) {
-            order = comparator.compare(e.getKey(), get(index).getKey());
-        } else {
-            @SuppressWarnings("unchecked") final Comparable<? super K> key =
-                    (Comparable<? super K>) e.getKey();
-            order = key.compareTo(get(index).getKey());
-        }
-        if (order != 0) {
-            // Allow replacement if the new key would be inserted adjacent to the replaced element.
-            final int insertionPoint = getInsertionPoint(e);
-            if (insertionPoint < index || insertionPoint > index + 1)
-                throw new IndexOutOfBoundsException("Wrong index given for element");
-        }
-        return super.set(index, e);
-    }
-
-    @Override
-    public Collection<E> values() {
-        return this;
-    }
-
-    private static final class KeyList<K, E extends Keyed<? extends K>>
-            extends AbstractList<K> implements Set<K> {
-        private final ObservableSortedKeyedArrayList<K, E> list;
-
-        private KeyList(final ObservableSortedKeyedArrayList<K, E> list) {
-            this.list = list;
-        }
-
-        @Override
-        public K get(final int index) {
-            return list.get(index).getKey();
-        }
-
-        @Override
-        public int size() {
-            return list.size();
-        }
-
-        @Override
-        @SuppressWarnings("EmptyMethod")
-        public Spliterator<K> spliterator() {
-            return super.spliterator();
-        }
-    }
-}

ui/src/main/java/com/wireguard/android/util/ObservableSortedKeyedList.java

@@ -1,19 +0,0 @@
-/*
- * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package com.wireguard.android.util;
-
-import com.wireguard.util.Keyed;
-import com.wireguard.util.NonNullForAll;
-import com.wireguard.util.SortedKeyedList;
-
-/**
- * A list that is both sorted/keyed and observable.
- */
-
-@NonNullForAll
-public interface ObservableSortedKeyedList<K, E extends Keyed<? extends K>>
-        extends ObservableKeyedList<K, E>, SortedKeyedList<K, E> {
-}

ui/src/main/java/com/wireguard/util/Keyed.java

@@ -1,15 +0,0 @@
-/*
- * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package com.wireguard.util;
-
-/**
- * Interface for objects that have a identifying key of the given type.
- */
-
-@NonNullForAll
-public interface Keyed<K> {
-    K getKey();
-}

ui/src/main/java/com/wireguard/util/KeyedList.java

@@ -1,33 +0,0 @@
-/*
- * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package com.wireguard.util;
-
-import java.util.Collection;
-import java.util.List;
-
-import androidx.annotation.Nullable;
-
-/**
- * A list containing elements that can be looked up by key. A {@code KeyedList} cannot contain
- * {@code null} elements.
- */
-
-@NonNullForAll
-public interface KeyedList<K, E extends Keyed<? extends K>> extends List<E> {
-    boolean containsAllKeys(Collection<K> keys);
-
-    boolean containsKey(K key);
-
-    @Nullable
-    E get(K key);
-
-    @Nullable
-    E getLast(K key);
-
-    int indexOfKey(K key);
-
-    int lastIndexOfKey(K key);
-}

ui/src/main/java/com/wireguard/util/SortedKeyedList.java

@@ -1,32 +0,0 @@
-/*
- * Copyright © 2017-2019 WireGuard LLC. All Rights Reserved.
- * SPDX-License-Identifier: Apache-2.0
- */
-
-package com.wireguard.util;
-
-import java.util.Collection;
-import java.util.Comparator;
-import java.util.Set;
-
-import androidx.annotation.Nullable;
-
-/**
- * A keyed list where all elements are sorted by the comparator returned by {@code comparator()}
- * applied to their keys.
- */
-
-@NonNullForAll
-public interface SortedKeyedList<K, E extends Keyed<? extends K>> extends KeyedList<K, E> {
-    Comparator<? super K> comparator();
-
-    @Nullable
-    K firstKey();
-
-    Set<K> keySet();
-
-    @Nullable
-    K lastKey();
-
-    Collection<E> values();
-}

ui/src/main/res/layout/app_list_dialog_fragment.xml

@@ -15,7 +15,7 @@
 
         <variable
             name="appData"
-            type="com.wireguard.android.util.ObservableKeyedList&lt;String, ApplicationData&gt;" />
+            type="com.wireguard.android.databinding.ObservableKeyedArrayList&lt;String, ApplicationData&gt;" />
     </data>
 
     <FrameLayout

ui/src/main/res/layout/app_list_item.xml

@@ -8,7 +8,7 @@
 
         <variable
             name="collection"
-            type="com.wireguard.android.util.ObservableKeyedList&lt;String, com.wireguard.android.model.ApplicationData&gt;" />
+            type="com.wireguard.android.databinding.ObservableKeyedArrayList&lt;String, com.wireguard.android.model.ApplicationData&gt;" />
 
         <variable
             name="key"

ui/src/main/res/layout/tunnel_list_fragment.xml

@@ -17,7 +17,7 @@
 
         <variable
             name="tunnels"
-            type="com.wireguard.android.util.ObservableKeyedList&lt;String, ObservableTunnel&gt;" />
+            type="com.wireguard.android.databinding.ObservableKeyedArrayList&lt;String, ObservableTunnel&gt;" />
     </data>
 
     <androidx.coordinatorlayout.widget.CoordinatorLayout

ui/src/main/res/layout/tunnel_list_item.xml

@@ -11,7 +11,7 @@
 
         <variable
             name="collection"
-            type="com.wireguard.android.util.ObservableKeyedList&lt;String, ObservableTunnel&gt;" />
+            type="com.wireguard.android.databinding.ObservableKeyedArrayList&lt;String, ObservableTunnel&gt;" />
 
         <variable
             name="key"