如何在一定时间后调用方法 repaint()

Question

我想更新工具提示，所以我想使用重绘方法，每 30 秒重绘一次框架，但它不起作用。谁能帮帮我..

GrphicsTut 方法

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.Timer;
import javax.swing.ImageIcon;
import javax.swing.JFrame;

public class GrphicsTut extends JFrame{
    Timer timer; 
    Image image;
    Image image2;
    int x1,y1,x2,y2;
    Font fonte = new Font("TimesRoman ",Font.BOLD,100);

    public GrphicsTut(){
        MouseListenerJ bkg = new MouseListenerJ();
        this.setTitle("Remember g for Graphics");
        this.setSize(600,500);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setVisible(true);
        this.addMouseMotionListener(bkg);
        this.addMouseListener(bkg);
        this.add(bkg);
    }

    public void paint(Graphics gr){ 
        gr.setFont(fonte);
        gr.setColor(Color.black);
        gr.drawLine(35,35, 410, 110);
        gr.drawLine(410,110, 310, 410);
        ImageIcon i=new ImageIcon("image/1005511030.jpg");
        image=i.getImage();
        gr.drawImage(image, 35, 35,null);
        gr.drawImage(image, 400, 100,null);
        gr.drawImage(image, 300, 400,null);
        repaint();
    }

    public static void main(String[] args) {
        new GrphicsTut();
    }
}

这里是 MouseListner 的方法

package Carte;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import javax.swing.ImageIcon;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
public class MouseListenerJ extends JPanel implements MouseListener, MouseMotionListener {
    public MouseListenerJ(){}
    public void paint(Graphics g){}

    @Override
    public void mouseClicked(MouseEvent me) {
        // TODO Auto-generated method stub
        if(me.getX()>=35 && me.getX()<=70 && me.getY()>=35 &&me.getY()<=70){
            //JOptionPane.showMessageDialog(null,"Que voulez vous faire");
            new Carte1();
        }       
    }

    @Override
    public void mouseEntered(MouseEvent me) {
        // TODO Auto-generated method stub
        //System.out.println("Entered at x "+me.getX());
    }

    @Override
    public void mouseExited(MouseEvent me) {
        // TODO Auto-generated method stub
        //System.out.println("Exited"); 
    }

    @Override
    public void mousePressed(MouseEvent me) {
        // TODO Auto-generated method stub
        System.out.println("Pressed at : "+me.getX()+" "+me.getY());
    }

    @Override
    public void mouseReleased(MouseEvent arg0) {
        // TODO Auto-generated method stub
        System.out.println("released");
    }

    @Override
    public void mouseDragged(MouseEvent arg0) {
        // TODO Auto-generated method stub  
    }

    @Override
    public void mouseMoved(MouseEvent me) {
        // TODO Auto-generated method stub
        if(me.getX()>=35 && me.getX()<=70 && me.getY()>=35 && me.getY()<=70){
            //JOptionPane.showMessageDialog(null,"Que voulez vous faire");
            this.setToolTipText("text");
            System.out.println(me.getX()+"  "+me.getY());
        }
        else if(me.getX()>=400 && me.getX()<=470 && me.getY()>=100 && me.getY(<=170){
            this.setToolTipText("Text 2");
            System.out.println(me.getX()+"  "+me.getY());
        }
    }   
}

Answer 1

考虑使用本机 Swing 组件来实现您的目标。它们提供您想要的所有功能：

• 处理鼠标点击
• 显示工具提示
• 显示图片

这里有一个小sn-p，教你如何使用JButton：

import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.net.MalformedURLException;
import java.net.URL;

import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.SwingUtilities;

public class TestButtons {

    protected void initUI() throws MalformedURLException {
        JFrame frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JPanel panel = new JPanel(new GridLayout(2, 2, 20, 20));
        panel.add(createButton("https://pbs.twimg.com/profile_images/378800000534649369/489a1e058bea59b62fd73c56f4bcb6c7.jpeg"));
        panel.add(createButton("https://pbs.twimg.com/profile_images/378800000714838591/ebbde1563faae6da2be79df945a7a02b.jpeg"));
        panel.add(createButton("https://pbs.twimg.com/profile_images/3477392906/f1907df0bd76668deac4a5e31a22fbe7.jpeg"));
        panel.add(createButton("https://pbs.twimg.com/profile_images/2718799802/9567ed3c3299f6f6ab1ffcbcbfd93da5.jpeg"));
        frame.add(panel);
        frame.pack();
        frame.setVisible(true);
    }

    private JButton createButton(final String url) throws MalformedURLException {
        final JButton button = new JButton(new ImageIcon(new URL(url)));
        button.setToolTipText("You are looking at image located at " + url);
        button.setBorderPainted(false);
        button.setContentAreaFilled(false);
        button.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                JOptionPane.showMessageDialog(button,
                        "You clicked on image located at " + url);
            }
        });
        return button;
    }

    /**
     * @param args
     */
    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    new TestButtons().initUI();
                } catch (MalformedURLException e) {
                    e.printStackTrace();
                }
            }
        });
    }

}