Question about Layout

I want to place JLabels as a NxN grids at the upper-left corncer of a JPanel.
And, I want there is no gap between components (JLabels)

I faced few problems

Problem 1:
I have tried use “null” layout and set the location manually that I did what I want. However, it doesn’t work when I add the JPanel onto JScrollPane.

Code:

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......
JPanel panel = new JPanel();
JPanel paneMain = new JPanel();
panel.setLayout( null ); [COLOR="Lime"]// no layout manager[/COLOR]
panelCenter.setLayout( new BorderLayout() ); [COLOR="Lime"]// use BorderLayout[/COLOR]
.......[COLOR="Lime"]// create others components[/COLOR]
[COLOR="Lime"]// add the panel onto a JScrollPane[/COLOR]
JScrollPane scrollPane = new JScrollPane( panel );

paneMain.add( scrollPane, BorderLayout.CENTER );
......[COLOR="Lime"]// add other components onto the paneMain[/COLOR]
[COLOR="Lime"]// add the paneMain onto the frame[/COLOR]
this.add( panelCenter, BorderLayout.CENTER );

......[COLOR="Lime"]// add other JPanels onto the frame[/COLOR]

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The following is the code about placing the JLabels onto the panel
labelInWorld[ ][ ] is a 2D-array of JLabel which is initialized already
The size of each JLabel is 50x50 which is set already.

Code:

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for( int i = 0; i < N; i++ )
{
        for( int j = 0; j < N; j++ )
        {
                labelInWorld[ i ][ j ].setLocation( j*50, i* 50 );
                panel.add( labelInWorld[ i ][ j ] );
        } [COLOR="Lime"]// end 2nd for loop[/COLOR]
} [COLOR="Lime"]// end 1st for loop[/COLOR]

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When N is large, the JPanel cannot display all the JLabels. The scrollbar should be appeared but it didn't. What is the problem?
Is the problem about using "null" layout?

Problem 2:
Besides using “null” layout, what layout manager I can use?

Thank you.

GridBagLayout and set the borders of the JLabels to an EmptyBorder of size 0.

Quote:

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Originally Posted by masijade

GridBagLayout and set the borders of the JLabels to an EmptyBorder of size 0.

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What is the purpose of setting the borders of the JLabels to an EmptyBorder of size 0? is it used to fixed the size of JLabel?

Thank you for your reply.

It used to reduce the size of the label (since you say you want no space between them I would assume those 10 pixels they leave between the message and the edge of the label to also be too much).

Quote:

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Originally Posted by masijade

It used to reduce the size of the label (since you say you want no space between them I would assume those 10 pixels they leave between the message and the edge of the label to also be too much).

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Thank you and I am trying to use the GridBagLayout.
And, do you know the what's wrong in problem 1?

I guess that the JScrollPane cannot be used without layout manager, is that correct?

Don't know. Don't care. I do not use null layout. It is the "I give up" layout manager and leads to brittle, non-platform-independent GUIs.

Quote:

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Originally Posted by masijade

Don't know. Don't care. I do not use null layout. It is the "I give up" layout manager and leads to brittle, non-platform-independent GUIs.

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Thank you.