lab-05:

Working calculator

lab-05/src/CalculatorPane.java

@@ -0,0 +1,158 @@
+import javafx.event.EventHandler;
+import javafx.geometry.Insets;
+import javafx.geometry.Pos;
+import javafx.scene.control.Button;
+import javafx.scene.control.TextField;
+import javafx.scene.input.MouseEvent;
+import javafx.scene.layout.*;
+import javafx.scene.paint.Paint;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class CalculatorPane extends VBox implements EventHandler<MouseEvent> {
+
+    private Button[] btnList;
+    private TextField ioField;
+
+    private boolean subtracting;
+
+    private int firstOperand;
+
+
+    public CalculatorPane(){
+        constructButtons();
+        setSpacing(15);
+        setPadding(new Insets(10));
+        ioField = new TextField();
+        ioField.setPrefColumnCount(15);
+        ioField.setEditable(false);
+        ioField.setText("");
+        ioField.setPrefHeight(15);
+
+
+    }
+
+
+    private void calculateAndDisplay() {
+        if (subtracting) {
+            display(String.valueOf(firstOperand - Integer.parseInt(ioField.getText())));
+        }
+        else display(String.valueOf(firstOperand+Integer.parseInt(ioField.getText())));
+    }
+
+    private void clear() {
+        this.firstOperand = 0;
+        ioField.setText("");
+        subtracting = false; //defualt to adding
+    }
+
+    private void add() {
+        firstOperand = Integer.parseInt(ioField.getText());
+        subtracting = false;
+    }
+
+    private void subtract() {
+        firstOperand = Integer.parseInt(ioField.getText());
+        subtracting = true;
+    }
+
+    private void display(String result) {
+        ioField.setText(result);
+    }
+
+    @Override
+    public void handle(MouseEvent mouseEvent) {
+        int pressedBtn = 0;
+        for (int i = 0; i < btnList.length; i++) {
+            if (btnList[i] == mouseEvent.getSource()){
+                pressedBtn = i;
+            }
+        }
+        System.out.println(mouseEvent.getSource() + "Clicked");
+        if (firstOperand == 0) {
+            //if there is no op yet, append to io.
+            ioField.setText(ioField.getText()+ pressedBtn);
+        }
+        else {
+            ioField.setText(String.valueOf(pressedBtn));
+        }
+    }
+
+    private void constructButtons(){
+        btnList = new Button[14];
+        btnList[Buttons.ZERO] = new Button("0");//Index 0
+        btnList[Buttons.ONE] = new Button("1");//Index 1
+        btnList[Buttons.TWO] = new Button("2");// ...
+        btnList[Buttons.THREE] = new Button("3");
+        btnList[Buttons.FOUR] = new Button("4");
+        btnList[Buttons.FIVE] = new Button("5");
+        btnList[Buttons.SIX] = new Button("6");
+        btnList[Buttons.SEVEN] = new Button("7");
+        btnList[Buttons.EIGHT] = new Button("8");
+        btnList[Buttons.NINE] = new Button("9");
+        btnList[Buttons.PLUS] = new Button("+");
+        btnList[Buttons.MINUS] = new Button("-");
+        btnList[Buttons.EQUAL] = new Button("=");
+        btnList[Buttons.CLEAR] = new Button("C");//Index 14
+        for (Button btn : btnList){
+            btn.setPrefSize(50,50);
+            btn.setOnMouseClicked(this);
+        }
+
+        btnList[Buttons.CLEAR].setOnMouseClicked(e-> clear());
+        btnList[Buttons.PLUS].setOnMouseClicked(e -> add());
+        btnList[Buttons.MINUS].setOnMouseClicked(e -> subtract());
+        btnList[Buttons.EQUAL].setOnMouseClicked(e -> calculateAndDisplay());
+
+        HBox firstRow = new HBox();
+        HBox secondRow = new HBox();
+        HBox thirdRow = new HBox();
+        HBox fourthRow = new HBox();
+        HBox fifthRow = new HBox();
+        firstRow.setSpacing(20);
+        firstRow.setAlignment(Pos.CENTER);
+        secondRow.setSpacing(20);
+        secondRow.setAlignment(Pos.CENTER);
+        thirdRow.setSpacing(20);
+        thirdRow.setAlignment(Pos.CENTER);
+        fourthRow.setSpacing(20);
+        fourthRow.setAlignment(Pos.CENTER);
+        fifthRow.setSpacing(20);
+        fifthRow.setAlignment(Pos.CENTER);
+
+        firstRow.getChildren().addAll(
+                btnList[Buttons.ONE], btnList[Buttons.TWO], btnList[Buttons.THREE]
+        );
+        secondRow.getChildren().addAll(
+                btnList[Buttons.FOUR], btnList[Buttons.FIVE], btnList[Buttons.SIX]
+        );
+        thirdRow.getChildren().addAll(
+                btnList[Buttons.SEVEN], btnList[Buttons.EIGHT], btnList[Buttons.NINE]
+        );
+        fourthRow.getChildren().addAll(
+                btnList[Buttons.PLUS], btnList[Buttons.MINUS], btnList[Buttons.ZERO]
+        );
+        fifthRow.getChildren().addAll(
+                btnList[Buttons.EQUAL], btnList[Buttons.CLEAR]
+        );
+        getChildren().addAll(ioField, firstRow, secondRow, thirdRow, fourthRow, fifthRow);
+    }
+
+    private final class Buttons {
+        public final static int ZERO = 0;
+        public final static int ONE = 1;
+        public final static int TWO = 2;
+        public final static int THREE = 3;
+        public final static int FOUR = 4;
+        public final static int FIVE = 5;
+        public final static int SIX = 6;
+        public final static int SEVEN = 7;
+        public final static int EIGHT = 8;
+        public final static int NINE = 9;
+        public final static int PLUS = 10;
+        public final static int MINUS = 11;
+        public final static int EQUAL = 12;
+        public final static int CLEAR = 13;
+    }
+}

lab-05/src/Main.java

@@ -9,9 +9,9 @@ public class Main extends Application {
 
     @Override
     public void start(Stage primaryStage) throws Exception{
-        Pane root = new Pane();
-        primaryStage.setTitle("Hello World");
-        primaryStage.setScene(new Scene(root, 300, 275));
+        CalculatorPane root = new CalculatorPane();
+        primaryStage.setTitle("Calculator");
+        primaryStage.setScene(new Scene(root, 300, 400));
         primaryStage.show();
     }