Thread: JPanel inside CENTER of BorderLayout is given GRID LAYOUT

import java.awt.*;
import javax.swing.*;
public class SSCCE extends JFrame {
 
	public static void main(String[] args)
	{
		//This block creates a panel(which uses grid layout) to put in the center of a border layout
		JPanel center = new JPanel();
		center.setVisible(true);
		center.setBackground(Color.red);
		center.setLayout(new GridLayout(10,10));
		fillGrid(center, 10*10);
 
		// a scroller is needed for functionality
		JScrollPane centerScroller = new JScrollPane(center,JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
 
		//setting up the frame
		SSCCE frame = new SSCCE();
		frame.setLayout(new BorderLayout());
		frame.add(centerScroller,BorderLayout.CENTER);
 
		frame.setSize(100, 100);
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setVisible(true);
	} // end main
 
	public static void fillGrid(JPanel center, int totalGrids)
	{
		JPanel temp;
 
		for(int i = 0; i < totalGrids; i++)
		{
			temp = new JPanel();
			Dimension size = new Dimension(10, 10);
			temp.setSize(size);
			temp.setPreferredSize(size);
			temp.setMinimumSize(size);
			temp.setMaximumSize(size);
			// temp.setResizeable(false); not an option for JPanels
			center.add(temp);
 
			if(i == 1 || i == 44) //for visual aid
			{
				temp.setBackground(Color.yellow);
			}
		}
	} //end fillGrid method
}

I know layout managers have magical powers to do what they need to do, just wish there was more documentation to predict their dictator regimes!

Thanks for taking a look,
Jonathan

I took out the scroller and it didn't make a difference as I suspected. (but it is needed to test the behavior of window resizing)

ha ha, will do. Can I ask why?

JPanels are weak mindless creatures, they need to grow some back bone and stand up to those Layout managers. I am close to giving up and either not using a layout manager, or trying something other then JPanels that can have its size locked.

Even shorter SSCCE

This code just uses GridLayout, and fills it with exactly as many JPanels as needed to fill the grid.
in this demo we have 10x10 grid, filled with 100 JPanels, they order properly (10 Columbus, 10 rows)
but I cant get them to stay one size... AND I HAVE TRIED 3000+ lines of code in options.

import java.awt.*;
import javax.swing.*;
public class SSCCE extends JFrame {
 
	public static void main(String[] args)
	{
 
		//This block creates a panel(which uses grid layout)
		JPanel center = new JPanel();
		center.setVisible(true);
		center.setBackground(Color.red);
		center.setLayout(new GridLayout(10,10));
 
 
		//This all does nothing from what I can tell
		Dimension forceMe = new Dimension(100, 100);
		center.setSize(forceMe);
		center.setPreferredSize(forceMe);
		center.setMinimumSize(forceMe);
		center.setMaximumSize(forceMe);
 
		//This fills the Grid with 100 JPanels using a simple for loop.
		fillGrid(center, 10*10);
 
		//setting up the frame
		SSCCE frame = new SSCCE();
		frame.add(center);
 
		frame.setSize(100, 100);
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setVisible(true);
	} // end main
 
 
	// Attempt to make a method to fills the grid with JPanels that keep their size.
	// All the sizing attemps seem to be efforts wasted.
	public static void fillGrid(JPanel center, int totalGrids)
	{
		JPanel temp;
 
		for(int i = 0; i < totalGrids; i++)
		{
			temp = new JPanel();
			Dimension size = new Dimension(10, 10);
			temp.setSize(size);
			temp.setPreferredSize(size);
			temp.setMinimumSize(size);
			temp.setMaximumSize(size);
			// temp.setResizeable(false); not an option for JPanels
			center.add(temp);
 
			if(i == 1 || i == 44) //for visual aid
			{
				temp.setBackground(Color.yellow);
			}
		}
	} //end fillGrid method
}

[Mark as solved]
Well, good thing you kept insisting on a wrapper Copeg, I tried it again after 100 other things, and it worked this time.
No idea how I failed to add it right the first time, must have gotten mixed up with my scroller.