【发布时间】：2016-08-14 01:43:10
【问题描述】：
我正在尝试在以下程序上设置按钮，但它们无法正确控制程序。我不确定他们为什么不工作。反向按钮有效，但开始和停止按钮无效。
import javafx.animation.KeyFrame;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.application.Platform;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.Pane;
import javafx.scene.paint.Color;
import javafx.scene.shape.Arc;
import javafx.scene.shape.ArcType;
import javafx.scene.shape.Circle;
import javafx.stage.Stage;
import javafx.util.Duration;
public class ch30 extends Application {
@Override // Override the start method in the Application class
public void start(Stage primaryStage) {
FanPane fan = new FanPane();
HBox hBox = new HBox(5);
Button btPause = new Button("Pause");
Button btResume = new Button("Resume");
Button btReverse = new Button("Reverse");
hBox.setAlignment(Pos.CENTER);
hBox.getChildren().addAll(btPause, btResume, btReverse);
BorderPane pane = new BorderPane();
pane.setCenter(fan);
pane.setBottom(hBox);
// Create a scene and place it in the stage
Scene scene = new Scene(pane, 200, 200);
primaryStage.setTitle("Exercise15_28"); // Set the stage title
primaryStage.setScene(scene); // Place the scene in the stage
primaryStage.show(); // Display the stage
//Runnable first = new Begin();
//Thread first = new Thread();
//t1.start();
Thread first = new Thread(new Runnable() {
@Override public void run() {
while (true) {
try {
//Pause
Thread.sleep(100);
} catch (InterruptedException ex) {
ex.printStackTrace();
}
Platform.runLater(new Runnable() {
@Override public void run() {
fan.move();
}
});
}
}
});
first.start();
//Timeline animation = new Timeline(
//new KeyFrame(Duration.millis(100), e -> fan.move()));
//animation.setCycleCount(Timeline.INDEFINITE);
//animation.play(); // Start animation
scene.widthProperty().addListener(e -> fan.setW(fan.getWidth()));
scene.heightProperty().addListener(e -> fan.setH(fan.getHeight()));
//btPause.setOnAction(e -> first.wait());
btResume.setOnAction(e -> first.start());
btReverse.setOnAction(e -> fan.reverse());
}
/**
* The main method is only needed for the IDE with limited
* JavaFX support. Not needed for running from the command line.
*/
public static void main(String[] args) {
launch(args);
}
}
class FanPane extends Pane {
private double w = 200;
private double h = 200;
private double radius = Math.min(w, h) * 0.45;
private Arc arc[] = new Arc[4];
private double startAngle = 30;
private Circle circle = new Circle(w / 2, h / 2, radius);
public FanPane() {
circle.setStroke(Color.BLACK);
circle.setFill(Color.WHITE);
getChildren().add(circle);
for (int i = 0; i < 4; i++) {
arc[i] = new Arc(w / 2, h / 2, radius * 0.9, radius * 0.9, startAngle + i * 90, 35);
arc[i].setFill(Color.RED); // Set fill color
arc[i].setType(ArcType.ROUND);
getChildren().addAll(arc[i]);
}
}
private double increment = 5;
public void reverse() {
increment = -increment;
}
public void move() {
setStartAngle(startAngle + increment);
}
public void setStartAngle(double angle) {
startAngle = angle;
setValues();
}
public void setValues() {
radius = Math.min(w, h) * 0.45;
circle.setRadius(radius);
circle.setCenterX(w / 2);
circle.setCenterY(h / 2);
for (int i = 0; i < 4; i++) {
arc[i].setRadiusX(radius * 0.9);
arc[i].setRadiusY(radius * 0.9);
arc[i].setCenterX(w / 2);
arc[i].setCenterY(h / 2);
arc[i].setStartAngle(startAngle + i * 90);
}
}
public void setW(double w) {
this.w = w;
setValues();
}
public void setH(double h) {
this.h = h;
setValues();
}
}
【问题讨论】：
-
wait不会停止线程，而是让当前（调用）线程等待，直到有人在同一对象上调用notify。看看this question
标签： multithreading javafx