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Adding ScrollBars to JPanel

Hi ,

I have JFrame, over which i have a JInternalFrame. On this JInternalFrame i am displaying an Image using JPanel, ie JPanel which contains the image is placed on JInternalFrame.

Code is like this.

class myclass extends JPanel{
...
----
// constructor
myclass()
{
-- --
--
JScrollPane scroll = new JScrollPane(this);

}

}
i have set the color of scrollpane to white(for testing the presence)

When the image is displayed the scrollpane appears as a bar next to image,
when the image is zoomed, this bar disappears and the image is zoomed, but no scrollbars appear.

can i get help for this,

regards

weelink

How did you filled the scrollpane with the image?

Mayank S

JScrollPane scroll = new JScrollPane ( this, ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED, ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED ) ;

Mayank.

weelink

When I want a image with scrollbars I do the following:

ImageIcon image = new ImageIcon("image.gif");
JLabel lblImage = new JLabel(image);

JScrollPane scrollPane = new JScrollPane(lblImage);

Does this help?

weelink

You could take a look here:

http://java.sun.com/docs/books/tutorial/uiswing/components/scrollpane.html

alpjose

ASKER

Hi ,

I have added image to JPanel. then added this JPanel to JScrollPane.
This object of scrollpane is called in another class which is JInternalFrame.

When the image is zoomed the scrollbars appear and if the mouse is just moved a bit on the image immediately the scrollbars disappear.

this is the problem.

i have used this.

JScrollPane scroll = new JScrollPane ( this, ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED, ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED ) ;

thanks and regards

Mayank S

Try:

JScrollPane scroll = new JScrollPane ( this, ScrollPaneConstants.VERTICAL_SCROLLBAR_ALWAYS, ScrollPaneConstants.HORIZONTAL_SCROLLBAR_ALWAYS ) ;

Mayank.

alpjose

ASKER

mayank, i have tried this also, same thing happens, when the image is zoomed, scrollbars appear and when the mouse is just moved on the image , i think when it get repainted it immediately disappears,
what can be be done for this

weelink

Did you implement a MouseListener somewhere?

alpjose

ASKER

yes i have implemented MouseListener,

weelink

Does this MouseListener has anything to do with the scrollpane? And if so, could you post the code?

alpjose

ASKER

Now the Scrollbars doesn't disappear, the scrollbars(both horizontal and vertical) are visible.

I have set the preferredSize(800,800);, so it is appearing, but when the scrollbars are scrolled, without zooming, repainting becomes very slow it becomes alright when i minimize and maximize the window, is there a way out of this.

once zoomed and scrolled, it works quiet OK,not perfectly.

ASKER CERTIFIED SOLUTION

Mayank S

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alpjose

ASKER

Hi,
Thank you , it works properly.
The Component's setPreferredSize() method has to be used for the JScrollpane to work properly.

And for repaint problem, in the paint method paintComponent() method has to be used.

it works fine.

Pls close this question

Thanks and Regards

CleanupPing

alpjose:
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Mayank S

Recommendation: Accept mayankeagle's comment as answer.