Drawing lines/circles in Swing

did u try repaint()???

vemul

set the pen color of the graphics object to soemthing other that the bg color of the panel...
g.setColor(Color.red);

Or you can use the Graphics object's methods to draw lines and arcs:-

g.drawLine(.....)
g.drawArc(.....)

see the java doc apis for info on the arguments....

Well, the super.paintComponent() part already happens, so the problem definitely lies somewhere else.

repaint() -- as in from where ?

yeah, the pen color is set to one diff. from the background. and no, the g.drawLine didnt work :(

am increasing the points, seems like the question is not so trivial :)
--Ankur.

if the super paints first (as above) then try to invalidate() the panel after you painting is done... or directly issue the repaint()..  the repaint should be on the overridden panel.

randy

hie randy,
Sorry, none of them worked :(
I think I'll give the general structure of the code, maybe it'll help you identify the problem better...

-----------------------------------------------------------
Draw objDraw = new Draw();
myFrame.getContentPane().add(BorderLayout.CENTER,objDraw);
.
.
.
.

in the file Draw.java

class Draw() extends JPanel...
{

public void paintComponent()
{
super.paintComponent();
Graphics2D g2 = (Graphics2D) g;
drawShapes(g2);
}      

public void drawShapes(Graphics2D g2)
{
        g2.setPaint(axis);
        g2.setStroke(dashed);
        g2.draw(new Line2D.Double(wt/2,0,wt/2,ht));
        g2.draw(new Line2D.Double(0,ht/2,wt,ht/2));
}
}// end of class Draw


Thanx for the prompt replies anyway :)

--Ankur.

hie randy,
Sorry, none of them worked :(
I think I'll give the general structure of the code, maybe it'll help you identify the problem better...

-----------------------------------------------------------
Draw objDraw = new Draw();
myFrame.getContentPane().add(BorderLayout.CENTER,objDraw);
.
.
.
.

in the file Draw.java

class Draw() extends JPanel...
{

public void paintComponent()
{
super.paintComponent();
Graphics2D g2 = (Graphics2D) g;
drawShapes(g2);
}      

public void drawShapes(Graphics2D g2)
{
        g2.setPaint(axis);
        g2.setStroke(dashed);
        g2.draw(new Line2D.Double(wt/2,0,wt/2,ht));
        g2.draw(new Line2D.Double(0,ht/2,wt,ht/2));
}
}// end of class Draw


Thanx for the prompt replies anyway :)

--Ankur.

Your paintComponent method has the wrong signature, should be:

public void paintComponent(Graphics g)
{
   super.paintComponent(g);
   Graphics2D g2 = (Graphics2D) g;
   drawShapes(g2);
}      

hie randy,
Sorry, none of them worked :(
I think I'll give the general structure of the code, maybe it'll help you identify the problem better...

-----------------------------------------------------------
Draw objDraw = new Draw();
myFrame.getContentPane().add(BorderLayout.CENTER,objDraw);
.
.
.
.

in the file Draw.java

class Draw() extends JPanel...
{

public void paintComponent()
{
super.paintComponent();
Graphics2D g2 = (Graphics2D) g;
drawShapes(g2);
}      

public void drawShapes(Graphics2D g2)
{
        g2.setPaint(axis);
        g2.setStroke(dashed);
        g2.draw(new Line2D.Double(wt/2,0,wt/2,ht));
        g2.draw(new Line2D.Double(0,ht/2,wt,ht/2));
}
}// end of class Draw


Thanx for the prompt replies anyway :)

--Ankur.

Actually, in the code, it is the way it should be, i.e paintComponent(Graphics g) ... i did a mistake in copying it to the message board :((

--Ankur.

Actually, in the code, it is the way it should be, i.e paintComponent(Graphics g) ... i did a mistake in copying it to the message board :((

--Ankur.

Actually, in the code, it is the way it should be, i.e paintComponent(Graphics g) ... i did a mistake in copying it to the message board :((

--Ankur.

(stop hitting refresh) :-)

Thxn, seems like the problem was the wt and ht values not being assigned properly. A simple solution for a seemlingly complex problem.

--Ankur.

PS: Yeah, just realised the refreshing error :))