i have two questoin:
a. in method mousePressed() and mouseDragged(),how to save the initial coordinate of the mouse press?
b.i have saw many applets just draw a rectangle only when the mouse is released,how to let rectangle always show on the panel before the mouse is released?
who can show some code of it? Thanks.
I use a global value for rectangle co-ords which is set by a mouseAdaptor (mousePressed & mouseReleased)
I also have a listener implementing MouseMotionListener to track mouse moved.
I redraw the rectangle each time as the cursor moves. I generate the background ONCE as a BufferedImage and then its just a case of redisplaying the image and drawing over with a rectangle.
Regards,
MArk
Draw extends canvas {
boolean drawRect=false
int x1, y1, x2, y2
boolean drawFinal=false
paint(Graphics g) {
if(!drawRect) return
if(drawFinal)
g.setColor(Color.black)
else
g.setColor(Color.blue)
g.drawRect(x1, y1, x2-x1, y2-y1)
}
Listen implements mouseListener, MouseMotionListener {
mouseDragged(MouseEvent e) {
Draw.drawRect = true;
Draw.drawFinal = false;
Draw.x = e.getX();
Draw.y = e.getY();
}
mouseUp(MouseEvent e) {
Draw.drawFinal = true;
}
this is the basic skeleton code for this type of operation. of course you will have to add the listener, and the listener will have to have a reference to the drawer. but otherwise it should do what you want it to do. ohh and the method for mouseUp may not be right. it may have another name, or you may actually have to check the mouseEvent itself for this.