Prefer AppCompat classes

AppCompat is the preferred way to go for any app targetting
a wider range of SDKs.

Replace all activities and fragments with their AppCompat
variants and fixup method calls to use support variants.

Signed-off-by: Harsh Shandilya <me@msfjarvis.dev>

app/build.gradle

@@ -43,6 +43,8 @@ dependencies {
     implementation "com.google.dagger:dagger:$daggerVersion"
     implementation "com.android.databinding:library:$databindingVersion"
     implementation "com.android.support:support-annotations:$supportLibsVersion"
+    implementation "com.android.support:appcompat-v7:$supportLibsVersion"
+    implementation "com.android.support:preference-v7:$supportLibsVersion"
     implementation "com.commonsware.cwac:crossport:$crossportVersion"
     implementation "com.getbase:floatingactionbutton:$fabLibVersion"
     implementation "net.sourceforge.streamsupport:android-retrofuture:$streamsupportVersion"

app/src/main/java/com/wireguard/android/activity/BaseActivity.java

@@ -1,10 +1,10 @@
 package com.wireguard.android.activity;
 
-import android.app.Activity;
 import android.content.Intent;
 import android.databinding.CallbackRegistry;
 import android.databinding.CallbackRegistry.NotifierCallback;
 import android.os.Bundle;
+import android.support.v7.app.AppCompatActivity;
 
 import com.wireguard.android.Application;
 import com.wireguard.android.backend.GoBackend;
@@ -17,7 +17,7 @@ import java.util.Objects;
  * Base class for activities that need to remember the currently-selected tunnel.
  */
 
-public abstract class BaseActivity extends Activity {
+public abstract class BaseActivity extends AppCompatActivity {
     private static final String KEY_SELECTED_TUNNEL = "selected_tunnel";
 
     private final SelectionChangeRegistry selectionChangeRegistry = new SelectionChangeRegistry();

app/src/main/java/com/wireguard/android/activity/MainActivity.java

@@ -1,9 +1,10 @@
 package com.wireguard.android.activity;
 
-import android.app.Fragment;
-import android.app.FragmentTransaction;
 import android.content.Intent;
 import android.os.Bundle;
+import android.support.v4.app.Fragment;
+import android.support.v4.app.FragmentManager;
+import android.support.v4.app.FragmentTransaction;
 import android.util.Log;
 import android.view.Menu;
 import android.view.MenuItem;
@@ -28,6 +29,7 @@ public class MainActivity extends BaseActivity {
     private State state = State.EMPTY;
 
     private boolean moveToState(final State nextState) {
+        final FragmentManager fragmentManager = getSupportFragmentManager();
         Log.i(TAG, "Moving from " + state.name() + " to " + nextState.name());
         if (nextState == state) {
             return false;
@@ -37,16 +39,16 @@ public class MainActivity extends BaseActivity {
             return true;
         } else if (nextState.layer == state.layer + 1) {
             final Fragment fragment = Fragment.instantiate(this, nextState.fragment);
-            final FragmentTransaction transaction = getFragmentManager().beginTransaction()
+            final FragmentTransaction transaction = fragmentManager.beginTransaction()
                     .replace(R.id.master_fragment, fragment)
                     .setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
             if (state.layer > 0)
                 transaction.addToBackStack(null);
             transaction.commit();
         } else if (nextState.layer == state.layer - 1) {
-            if (getFragmentManager().getBackStackEntryCount() == 0)
+            if (fragmentManager.getBackStackEntryCount() == 0)
                 return false;
-            getFragmentManager().popBackStack();
+            fragmentManager.popBackStack();
         } else if (nextState.layer < state.layer - 1) {
             moveToState(State.ofLayer(state.layer - 1));
             moveToState(nextState);
@@ -121,8 +123,8 @@ public class MainActivity extends BaseActivity {
     }
 
     private void updateActionBar() {
-        if (getActionBar() != null)
+        if (getSupportActionBar() != null)
-            getActionBar().setDisplayHomeAsUpEnabled(state.layer > State.LIST.layer);
+            getSupportActionBar().setDisplayHomeAsUpEnabled(state.layer > State.LIST.layer);
     }
 
     private enum State {

app/src/main/java/com/wireguard/android/activity/SettingsActivity.java

@@ -1,10 +1,11 @@
 package com.wireguard.android.activity;
 
-import android.app.Activity;
 import android.content.pm.PackageManager;
 import android.os.Bundle;
-import android.preference.Preference;
+import android.support.annotation.NonNull;
-import android.preference.PreferenceFragment;
+import android.support.v7.app.AppCompatActivity;
+import android.support.v7.preference.Preference;
+import android.support.v7.preference.PreferenceFragmentCompat;
 
 import com.wireguard.android.Application;
 import com.wireguard.android.R;
@@ -19,7 +20,7 @@ import java.util.List;
  * Interface for changing application-global persistent settings.
  */
 
-public class SettingsActivity extends Activity {
+public class SettingsActivity extends AppCompatActivity {
     @FunctionalInterface
     public interface PermissionRequestCallback {
         void done(String[] permissions, int[] grantResults);
@@ -56,7 +57,7 @@ public class SettingsActivity extends Activity {
     }
 
     @Override
-    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
+    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
         final PermissionRequestCallback f = permissionRequestCallbacks.get(requestCode);
         if (f != null) {
             permissionRequestCallbacks.remove(requestCode);
@@ -67,17 +68,16 @@ public class SettingsActivity extends Activity {
     @Override
     protected void onCreate(final Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        if (getFragmentManager().findFragmentById(android.R.id.content) == null) {
+        if (getSupportFragmentManager().findFragmentById(android.R.id.content) == null) {
-            getFragmentManager().beginTransaction()
+            getSupportFragmentManager().beginTransaction()
                     .add(android.R.id.content, new SettingsFragment())
                     .commit();
         }
     }
 
-    public static class SettingsFragment extends PreferenceFragment {
+    public static class SettingsFragment extends PreferenceFragmentCompat {
         @Override
-        public void onCreate(final Bundle savedInstanceState) {
+        public void onCreatePreferences(final Bundle savedInstanceState, final String key) {
-            super.onCreate(savedInstanceState);
             addPreferencesFromResource(R.xml.preferences);
             if (Application.getComponent().getBackendType() != WgQuickBackend.class) {
                 final Preference toolsInstaller =

app/src/main/java/com/wireguard/android/activity/TunnelCreatorActivity.java

@@ -14,8 +14,8 @@ public class TunnelCreatorActivity extends BaseActivity {
     @SuppressWarnings("UnnecessaryFullyQualifiedName")
     protected void onCreate(final Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        if (getFragmentManager().findFragmentById(android.R.id.content) == null) {
+        if (getSupportFragmentManager().findFragmentById(android.R.id.content) == null) {
-            getFragmentManager().beginTransaction()
+            getSupportFragmentManager().beginTransaction()
                     .add(android.R.id.content, new TunnelEditorFragment())
                     .commit();
         }

app/src/main/java/com/wireguard/android/fragment/BaseFragment.java

@@ -1,7 +1,7 @@
 package com.wireguard.android.fragment;
 
-import android.app.Fragment;
 import android.content.Context;
+import android.support.v4.app.Fragment;
 
 import com.wireguard.android.activity.BaseActivity;
 import com.wireguard.android.activity.BaseActivity.OnSelectedTunnelChangedListener;

app/src/main/java/com/wireguard/android/preference/ToolsInstallerPreference.java

@@ -1,8 +1,8 @@
 package com.wireguard.android.preference;
 
 import android.content.Context;
-import android.preference.Preference;
 import android.support.annotation.NonNull;
+import android.support.v7.preference.Preference;
 import android.system.OsConstants;
 import android.util.AttributeSet;
 
@@ -37,17 +37,12 @@ public class ToolsInstallerPreference extends Preference {
 
     @Override
     public CharSequence getTitle() {
-        return getContext().getString(getTitleRes());
+        return getContext().getString(R.string.tools_installer_title);
     }
 
     @Override
-    public int getTitleRes() {
+    public void onAttached() {
-        return R.string.tools_installer_title;
+        super.onAttached();
-    }
-
-    @Override
-    protected void onAttachedToActivity() {
-        super.onAttachedToActivity();
         asyncWorker.supplyAsync(toolsInstaller::areInstalled).whenComplete(this::onCheckResult);
     }
 

app/src/main/java/com/wireguard/android/preference/ZipExporterPreference.java

@@ -1,9 +1,10 @@
 package com.wireguard.android.preference;
 
+import android.Manifest;
 import android.content.Context;
 import android.content.pm.PackageManager;
 import android.os.Environment;
-import android.preference.Preference;
+import android.support.v7.preference.Preference;
 import android.util.AttributeSet;
 import android.util.Log;
 
@@ -57,12 +58,7 @@ public class ZipExporterPreference extends Preference {
 
     @Override
     public CharSequence getTitle() {
-        return getContext().getString(getTitleRes());
+        return getContext().getString(R.string.zip_exporter_title);
-    }
-
-    @Override
-    public int getTitleRes() {
-        return R.string.zip_exporter_title;
     }
 
     private void exportZip() {
@@ -86,7 +82,8 @@ public class ZipExporterPreference extends Preference {
                             final ZipOutputStream zip = new ZipOutputStream(new FileOutputStream(file));
                             for (int i = 0; i < futureConfigs.size(); ++i) {
                                 zip.putNextEntry(new ZipEntry(tunnels.get(i).getName() + ".conf"));
-                                zip.write(futureConfigs.get(i).getNow(null).toString().getBytes(StandardCharsets.UTF_8));
+                                zip.write(futureConfigs.get(i).getNow(null).
+                                        toString().getBytes(StandardCharsets.UTF_8));
                             }
                             zip.closeEntry();
                             zip.close();
@@ -104,7 +101,9 @@ public class ZipExporterPreference extends Preference {
             final String error = ExceptionLoggers.unwrap(throwable).getMessage();
             final String message = getContext().getString(R.string.export_error, error);
             Log.e(TAG, message, throwable);
-            Snackbar.make(((SettingsActivity)getContext()).findViewById(android.R.id.content), message, Snackbar.LENGTH_LONG).show();
+            Snackbar.make(
+                    ((SettingsActivity)getContext()).findViewById(android.R.id.content),
+                    message, Snackbar.LENGTH_LONG).show();
         } else {
             exportedFilePath = filePath;
             setEnabled(false);
@@ -114,7 +113,9 @@ public class ZipExporterPreference extends Preference {
 
     @Override
     protected void onClick() {
-        ((SettingsActivity)getContext()).ensurePermissions(new String[] { "android.permission.WRITE_EXTERNAL_STORAGE" }, (permissions, granted) -> {
+        ((SettingsActivity)getContext()).ensurePermissions(
+                new String[] {Manifest.permission.WRITE_EXTERNAL_STORAGE},
+                (permissions, granted) -> {
                     if (granted.length > 0 && granted[0] == PackageManager.PERMISSION_GRANTED)
                         exportZip();
                 });