Paint Method

[JessyCute]

I try to draw the line like this on the screen, but when some menu show
up my line is not draw correctly. Anyone know how to solve it thankyou.

Follow this code. I tried paint() and paintComponent() but it doesn't
work both.

Code:



import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;

import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;

public class TestPaint extends JFrame{

public TestPaint(){
JMenuBar bar = new JMenuBar();
JMenu testM = new JMenu("TEST");
testM.add(new JMenuItem("test1-child"));
testM.add(new JMenuItem("test1-child"));

JMenu test1M = new JMenu("TEST1");
test1M.add(new JMenuItem("test1-child"));
test1M.add(new JMenuItem("test1-child"));
test1M.add(new JMenuItem("test1-child"));
test1M.add(new JMenuItem("test1-child"));
test1M.add(new JMenuItem("test1-child"));

JMenu test2M = new JMenu("TEST2");
test2M.add(new JMenuItem("test1-child"));
test2M.add(new JMenuItem("test1-child"));
test2M.add(new JMenuItem("test1-child"));
test2M.add(new JMenuItem("test1-child"));
test2M.add(new JMenuItem("test1-child"));

JMenu test3M = new JMenu("TEST2");
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));

bar.add(testM);
bar.add(test1M);
bar.add(test2M);
bar.add(test3M);

setJMenuBar(bar);

getContentPane().add(new TestPanel(), BorderLayout.CENTER);

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(400,400);
show();
}

class TestPanel extends JPanel{

/*public void paint(Graphics g) {
super.paint(g);
System.out.println("paint");
int x2 = ( int ) g.getClipBounds().getWidth();
int y = 100;
g.setColor( Color.RED );
g.drawLine( 0, y, x2, y );
}*/

protected void paintComponent(Graphics g) {
super.paintComponent(g);
System.out.println("paintComponent");
int x2 = ( int ) g.getClipBounds().getWidth();
int y = 100;
g.setColor( Color.RED );
g.drawLine( 0, y, x2, y );
}
}

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

 

[Bart Cremers]

When using the clipbounds to paint you'll have to make sure you take
the x position of the clip rectangle also into account:

int x1 = g.getClipBounds().x;
int x2 = x1 + g.getClipBounds().width;
int y = 100;
g.setColor(Color.RED);
g.drawLine(x1, y, x2, y);

Regards,

Bart

 

[Bart Rider]

I try to draw the line like this on the screen, but when some menu show
up my line is not draw correctly. Anyone know how to solve it thankyou.

Follow this code. I tried paint() and paintComponent() but it doesn't
work both.

Code:



import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;

import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;

public class TestPaint extends JFrame{

public TestPaint(){
JMenuBar bar = new JMenuBar();
JMenu testM = new JMenu("TEST");
testM.add(new JMenuItem("test1-child"));
testM.add(new JMenuItem("test1-child"));

JMenu test1M = new JMenu("TEST1");
test1M.add(new JMenuItem("test1-child"));
test1M.add(new JMenuItem("test1-child"));
test1M.add(new JMenuItem("test1-child"));
test1M.add(new JMenuItem("test1-child"));
test1M.add(new JMenuItem("test1-child"));

JMenu test2M = new JMenu("TEST2");
test2M.add(new JMenuItem("test1-child"));
test2M.add(new JMenuItem("test1-child"));
test2M.add(new JMenuItem("test1-child"));
test2M.add(new JMenuItem("test1-child"));
test2M.add(new JMenuItem("test1-child"));

JMenu test3M = new JMenu("TEST2");
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));
test3M.add(new JMenuItem("test1-child"));

bar.add(testM);
bar.add(test1M);
bar.add(test2M);
bar.add(test3M);

setJMenuBar(bar);

getContentPane().add(new TestPanel(), BorderLayout.CENTER);

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setSize(400,400);
show();
}

class TestPanel extends JPanel{

/*public void paint(Graphics g) {
super.paint(g);
System.out.println("paint");
int x2 = ( int ) g.getClipBounds().getWidth();
int y = 100;
g.setColor( Color.RED );
g.drawLine( 0, y, x2, y );
}*/

protected void paintComponent(Graphics g) {
super.paintComponent(g);
System.out.println("paintComponent");
int x2 = ( int ) g.getClipBounds().getWidth();
int y = 100;
g.setColor( Color.RED );
g.drawLine( 0, y, x2, y );
}
}

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

Use x2=getWidth(), so you draw from zero x coordinate to the
maximum (you may want to give credit to any border zone). If
you use the clip bounderies, the section to redraw might not
nessecarily start with x coordinate zero, but that was pointed
out by Bart Cremers before.

Just a hint to add:
dont use show any more, instead use setVisible(true) and before
the call to setVisible insert a pack() statement (together with
a new method in TestPanel called getMinimumSize)