commit Exercise_30_06

csv77 · csv77 · commit f037a2f7d75d · 2017-09-30T18:03:11.000+02:00
diff --git a/Chapter_30/exercise_30_06/BallPane.java b/Chapter_30/exercise_30_06/BallPane.java
@@ -0,0 +1,62 @@
+package exercise_30_06;
+
+import javafx.application.Platform;
+import javafx.scene.layout.Pane;
+import javafx.scene.paint.Color;
+import javafx.scene.shape.Circle;
+
+public class BallPane extends Pane {
+public final double radius = 20;
+    private double x = radius, y = radius;
+    private double dx = 1, dy = 1;
+    private Circle circle = new Circle(x, y, radius);
+    private int sleepTime = 10;
+    private Thread thread = new Thread(() -> {
+        try {
+            while(true) {
+                Platform.runLater(() -> moveBall());
+                Thread.sleep(sleepTime);
+            }
+        }
+        catch (InterruptedException ex) {
+        }
+    });
+
+    public BallPane() {
+        circle.setFill(Color.GREEN);
+        getChildren().add(circle);
+        thread.start();
+    }
+
+    public void resume() {
+        thread.resume();
+    }
+
+    public void suspend() {
+        thread.suspend();
+    }
+
+    public void increaseSpeed() {
+        if(sleepTime > 1) {
+            sleepTime--;
+        }
+    }
+
+    public void decreaseSpeed() {
+        sleepTime++;
+    }
+
+    protected void moveBall() {
+        if(x < radius || x > getWidth() - radius) {
+            dx *= -1;
+        }
+        if(y < radius || y > getHeight() - radius) {
+            dy *= -1;
+        }
+
+        x += dx;
+        y += dy;
+        circle.setCenterX(x);
+        circle.setCenterY(y);
+    }
+}
diff --git a/Chapter_30/exercise_30_06/Exercise_30_06.java b/Chapter_30/exercise_30_06/Exercise_30_06.java
@@ -0,0 +1,37 @@
+package exercise_30_06;
+
+import javafx.application.Application;
+import javafx.scene.Scene;
+import javafx.scene.input.KeyCode;
+import javafx.stage.Stage;
+
+public class Exercise_30_06 extends Application {
+    
+    @Override
+    public void start(Stage primaryStage) {
+        BallPane ballPane = new BallPane();
+
+        ballPane.setOnMousePressed(e -> ballPane.suspend());
+        ballPane.setOnMouseReleased(e -> ballPane.resume());
+
+        ballPane.setOnKeyPressed(e -> {
+          if (e.getCode() == KeyCode.UP) {
+            ballPane.increaseSpeed();
+          } 
+          else if (e.getCode() == KeyCode.DOWN) {
+            ballPane.decreaseSpeed();
+          }
+        });
+
+        Scene scene = new Scene(ballPane, 250, 150);
+        primaryStage.setTitle("Exercise_30_06");
+        primaryStage.setScene(scene);
+        primaryStage.show();
+
+        ballPane.requestFocus();
+    }
+
+    public static void main(String[] args) {
+        launch(args);
+    }
+}
