动态将按钮添加到JFrame或layeredPane

Question

public ChessGameDemo(){
Dimension boardSize = new Dimension(600, 600);

//  Using a Layered Pane 
layeredPane = new JLayeredPane();
add(layeredPane);
layeredPane.setPreferredSize(new Dimension(700,700));

//Create a reset button that will reset the game
JButton button = new JButton("Reset");
button.setPreferredSize(new Dimension(50,50));
add(button,BorderLayout.EAST);


//Add the chessboard to the Layered Pane 

chessBoard = new JPanel();
layeredPane.add(chessBoard, JLayeredPane.DEFAULT_LAYER);
chessBoard.setLayout( new GridLayout(8, 8) );
chessBoard.setPreferredSize( boardSize );
chessBoard.setBounds(0, 0, boardSize.width, boardSize.height);

for (int i = 0; i < 64; i++) {
    JPanel square = new JPanel( new BorderLayout() );
    chessBoard.add( square );

int row = (i / 8) % 2;
if (row == 0)
    square.setBackground( i % 2 == 0 ? Color.blue : Color.white );
else
    square.setBackground( i % 2 == 0 ? Color.white : Color.blue );
}

As you can see here, I am creating a chess board in a panel and adding that to a layered pane, which in turn is part of the frame. The idea is to have a menu bar and a couple of buttons to make it all look more presentable. But when I try to add the button it captures the entire height of the frame ignoring the dimension I have specified. I just see one tall button stretching the entire height of the window/frame. What is the mistake here? How do I add normal sized buttons dynamically here? that sits well next to the chessboard?

Answer 1

But when I try to add the button it captures the entire height of the frame ignoring the dimension I have specified.

That is the way BorderLayout.EAST works. Read the section from the Swing tutorial on Using Layout Managers for more information.

You can always nest layout manager to get your desired look for example:

JPanel east = new JPanel( new BorderLayout() );
JPanel buttons = new JPanel( new GridLayout(0, 1) );
east.add(buttons, BorderLayout.NORTH);
buttons.add( button1 );
buttons.add( button2 );
frame.add(east, BorderLayoutEAST);