Please help with a drawing on JPanel in a background.
Hello everybody,
I have already post this question in the main java forum and was adviced to place the question here. Since then, I have refactored the code. I need your opinion and advice.
My task is to draw some objects on the JPanel or some other components and to place the names to the objects, for example squares, but later, from the thread. Because it can take some time, untill the names will be avaliable.
So, I refactored the code I post before http://forum.java.sun.com/thread.jspa?threadID=5192586&tstart=15
And now, it draws on layers and from thread on resize, with some imitating interval.
Is it a good approach I use, is there a better way, to draw on JPanel, after some objects were already painted.
Here is my sample, try to resize window:
package test;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
import java.awt.geom.Rectangle2D;
import javax.swing.JFrame;
import javax.swing.JLayeredPane;
import javax.swing.JPanel;
publicclass Painterextends JFrameimplements ComponentListener{
privatestaticfinallong serialVersionUID = 1;
private ThreadPainter threadPainter;
JPanel panel =new JPanel(){
privatestaticfinallong serialVersionUID = 1;
@Override
protectedvoid paintComponent(Graphics g){
super.paintComponent(g);
System.out.println("repaint");
Graphics2D g2d = (Graphics2D) g;
g2d.setColor(Color.gray);
g2d.fillRect(0, 0, 800, 600);
g2d.setColor(Color.white);
for (int i = 0; i < 6; i++){
Rectangle2D rec2d =new Rectangle2D.Double(10 + i * 100,
10 + i * 100, 10, 10);
g2d.fill(rec2d);
g2d.drawString("Square " + i, 10 + i * 100 + 20, 10 + i * 100);
}
// start thread to paint some changes later
if (threadPainter ==null){
threadPainter =new ThreadPainter();
threadPainter.start();
}
}
};
JPanelTest panel1 =new JPanelTest();
publicclass JPanelTestextends JPanel{
privatestaticfinallong serialVersionUID = 1;
privateint times = 0;
@Override
protectedvoid paintComponent(Graphics g){
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
g2d.setColor(Color.red);
System.out.println("repaint panel test");
System.out.println("repaitn times");
g2d.drawString("Square " + times, 10 + times * 100 + 20, 10 + times * 100);
}
publicvoid repaintMethod(int times){
this.times = times;
this.repaint(times * 100 + 20, times * 100, 300,300);
};
};
publicclass ThreadPainterextends Thread{
privateboolean stop =false;
@Override
publicvoid run(){
while (!stop){
int cnt = 0;
for (int i = 0; i < 6; i++){
System.out.println("do task");
panel1.repaintMethod(i);
// load data, do calculations
try{
// emulate calcilation
Thread.sleep(1000);
}catch (InterruptedException e){
e.printStackTrace();
}
if (stop){
break;
}
cnt++;
}
if (cnt == 6){
stopThread();
}
}
};
publicvoid stopThread(){
this.stop =true;
};
};
public Painter(){
this.setLayout(new BorderLayout());
JLayeredPane pane =new JLayeredPane();
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setLocation(new Point(100, 100));
this.setPreferredSize(new Dimension(800, 600));
this.panel.setOpaque(false);
this.panel1.setOpaque(false);
pane.setOpaque(false);
pane.add(panel, JLayeredPane.DEFAULT_LAYER);
pane.add(panel1,new Integer(
JLayeredPane.DEFAULT_LAYER.intValue() + 1));
this.add(pane, BorderLayout.CENTER);
panel.setBounds(new Rectangle(0, 0, 800, 600));
panel1.setBounds(new Rectangle(0, 0, 800, 600));
this.addComponentListener(this);
}
publicstaticvoid main(String[] args){
Painter painter =new Painter();
painter.pack();
painter.setVisible(true);
}
@Override
publicvoid componentHidden(ComponentEvent e){
// TODO Auto-generated method stub
}
@Override
publicvoid componentMoved(ComponentEvent e){
// TODO Auto-generated method stub
}
@Override
publicvoid componentResized(ComponentEvent e){
if (threadPainter !=null){
threadPainter.stopThread();
threadPainter =new ThreadPainter();
threadPainter.start();
}
}
@Override
publicvoid componentShown(ComponentEvent e){
// TODO Auto-generated method stub
}
}
