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Java

Dennis Castillo
Dennis Castillo
16,018 Points
Posted by Dennis Castillo
Dennis Castillo
16,018 Points

How do I display graphics on Panel without an events?

Greetings folks,

Just practicing coding on Java using NetBeans 8.1, using GUI or drag and drop object interface. I have a problem displaying graphics on Panel, I have this code:

private void myPanel() {
        Graphics g = myPanel.getGraphics();
        Graphics2D g2 = (Graphics2D) g;
        g2.setStroke(new BasicStroke(5)); 
        g2.drawLine(10, 10, 10, 165);
        g2.drawLine(330, 165, 10, 165);
        g2.setColor(Color.LIGHT_GRAY);
        g2.drawLine(10, 10, 330, 10);
        g2.drawLine(330, 165, 330, 10);
    }

but it won't display, I probably missing something but i don't know what it is and don't know how to use it.

I switch to an event, add some button and put this code in it:

private void btnCalculateMouseClicked(java.awt.event.MouseEvent evt) {                                          
        Graphics g = myPanel.getGraphics();
        Graphics2D g2 = (Graphics2D) g;
        g2.setStroke(new BasicStroke(5)); 
        g2.drawLine(10, 10, 10, 165);
        g2.drawLine(330, 165, 10, 165);
        g2.setColor(Color.LIGHT_GRAY);
        g2.drawLine(10, 10, 330, 10);
        g2.drawLine(330, 165, 330, 10);
    }

And it did work, but this is an event. but what if don't need an event just displaying instantly once the program runs?

Thanks :)