如何使用SpringLayout和BorderLayout：
JPanel contentPane = new JPanel(new SpringLayout());
//...
contentPane.add(makeWrapper(label));
//...
private static JComponent makeWrapper(JComponent c) {
JPanel p = new JPanel(new BorderLayout());
p.add(c, BorderLayout.NORTH);
return p;
}
import java.awt.*;
import javax.swing.*;
public class LayoutTest {
public JComponent makeUI() {
JPanel contentPane = new JPanel(new SpringLayout());
for (int i = 0; i < 5; i++) {
JLabel label = new JLabel("Label: ");
JTextField textField = new JTextField("Text field", 15);
JTextArea textArea = new JTextArea("Text Area", 4, 40);
JScrollPane scrollPane = new JScrollPane(textArea);
contentPane.add(makeWrapper(label));
contentPane.add(makeWrapper(textField));
contentPane.add(scrollPane);
}
SpringUtilities.makeCompactGrid(contentPane, 5, 3, 1, 1, 1, 0);
return contentPane;
}
private static JComponent makeWrapper(JComponent c) {
JPanel p = new JPanel(new BorderLayout());
p.add(c, BorderLayout.NORTH);
return p;
}
// Another common way to use GridBagLayout:
public JComponent makeGridBagLayoutUI() {
JPanel contentPane = new JPanel(new GridBagLayout());
contentPane.setBorder(BorderFactory.createEmptyBorder(5, 0, 0, 5));
GridBagConstraints c = new GridBagConstraints();
c.insets = new Insets(0, 5, 5, 0);
c.gridy = 0;
for (int i = 0; i < 5; i++) {
JLabel label = new JLabel("Label: ");
JTextField textField = new JTextField("Text field", 15);
//JTextArea textArea = new JTextArea("Text Area", 3, 40);
//> JTaxtArea with height 4
int textAreaHeight = 4; //3
JTextArea textArea = new JTextArea("Text Area", textAreaHeight, 40);
JScrollPane scrollPane = new JScrollPane(textArea);
c.fill = GridBagConstraints.HORIZONTAL;
c.gridheight = 1;
c.weightx = 0d;
//c.weighty = 0d;
c.gridx = 0;
contentPane.add(label, c);
c.gridx = 1;
contentPane.add(textField, c);
c.gridx = 2;
c.gridheight = textAreaHeight;
c.weightx = 1d;
//c.weighty = 1d;
c.fill = GridBagConstraints.BOTH;
contentPane.add(scrollPane, c);
c.gridy += textAreaHeight;
}
return contentPane;
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override public void run() {
createAndShowGUI();
}
});
}
public static void createAndShowGUI() {
JFrame frame = new JFrame("test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(new LayoutTest().makeUI());
//frame.getContentPane().add(new LayoutTest().makeGridBagLayoutUI());
frame.pack();
//frame.setMinimumSize(frame.getSize());
frame.setVisible(true);
}
}
/*
* Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of Oracle or the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
class SpringUtilities {
/**
* A debugging utility that prints to stdout the component's
* minimum, preferred, and maximum sizes.
*/
public static void printSizes(Component c) {
System.out.println("minimumSize = " + c.getMinimumSize());
System.out.println("preferredSize = " + c.getPreferredSize());
System.out.println("maximumSize = " + c.getMaximumSize());
}
/**
* Aligns the first <code>rows</code> * <code>cols</code>
* components of <code>parent</code> in
* a grid. Each component is as big as the maximum
* preferred width and height of the components.
* The parent is made just big enough to fit them all.
*
* @param rows number of rows
* @param cols number of columns
* @param initialX x location to start the grid at
* @param initialY y location to start the grid at
* @param xPad x padding between cells
* @param yPad y padding between cells
*/
public static void makeGrid(Container parent,
int rows, int cols,
int initialX, int initialY,
int xPad, int yPad) {
SpringLayout layout;
try {
layout = (SpringLayout)parent.getLayout();
} catch (ClassCastException exc) {
System.err.println("The first argument to makeGrid must use SpringLayout.");
return;
}
Spring xPadSpring = Spring.constant(xPad);
Spring yPadSpring = Spring.constant(yPad);
Spring initialXSpring = Spring.constant(initialX);
Spring initialYSpring = Spring.constant(initialY);
int max = rows * cols;
//Calculate Springs that are the max of the width/height so that all
//cells have the same size.
Spring maxWidthSpring = layout.getConstraints(parent.getComponent(0)).
getWidth();
Spring maxHeightSpring = layout.getConstraints(parent.getComponent(0)).
getWidth();
for (int i = 1; i < max; i++) {
SpringLayout.Constraints cons = layout.getConstraints(
parent.getComponent(i));
maxWidthSpring = Spring.max(maxWidthSpring, cons.getWidth());
maxHeightSpring = Spring.max(maxHeightSpring, cons.getHeight());
}
//Apply the new width/height Spring. This forces all the
//components to have the same size.
for (int i = 0; i < max; i++) {
SpringLayout.Constraints cons = layout.getConstraints(
parent.getComponent(i));
cons.setWidth(maxWidthSpring);
cons.setHeight(maxHeightSpring);
}
//Then adjust the x/y constraints of all the cells so that they
//are aligned in a grid.
SpringLayout.Constraints lastCons = null;
SpringLayout.Constraints lastRowCons = null;
for (int i = 0; i < max; i++) {
SpringLayout.Constraints cons = layout.getConstraints(
parent.getComponent(i));
if (i % cols == 0) { //start of new row
lastRowCons = lastCons;
cons.setX(initialXSpring);
} else { //x position depends on previous component
cons.setX(Spring.sum(lastCons.getConstraint(SpringLayout.EAST),
xPadSpring));
}
if (i/cols == 0) { //first row
cons.setY(initialYSpring);
} else { //y position depends on previous row
cons.setY(Spring.sum(lastRowCons.getConstraint(SpringLayout.SOUTH),
yPadSpring));
}
lastCons = cons;
}
//Set the parent's size.
SpringLayout.Constraints pCons = layout.getConstraints(parent);
pCons.setConstraint(SpringLayout.SOUTH,
Spring.sum(
Spring.constant(yPad),
lastCons.getConstraint(SpringLayout.SOUTH)));
pCons.setConstraint(SpringLayout.EAST,
Spring.sum(
Spring.constant(xPad),
lastCons.getConstraint(SpringLayout.EAST)));
}
/* Used by makeCompactGrid. */
private static SpringLayout.Constraints getConstraintsForCell(
int row, int col,
Container parent,
int cols) {
SpringLayout layout = (SpringLayout) parent.getLayout();
Component c = parent.getComponent(row * cols + col);
return layout.getConstraints(c);
}
/**
* Aligns the first <code>rows</code> * <code>cols</code>
* components of <code>parent</code> in
* a grid. Each component in a column is as wide as the maximum
* preferred width of the components in that column;
* height is similarly determined for each row.
* The parent is made just big enough to fit them all.
*
* @param rows number of rows
* @param cols number of columns
* @param initialX x location to start the grid at
* @param initialY y location to start the grid at
* @param xPad x padding between cells
* @param yPad y padding between cells
*/
public static void makeCompactGrid(Container parent,
int rows, int cols,
int initialX, int initialY,
int xPad, int yPad) {
SpringLayout layout;
try {
layout = (SpringLayout)parent.getLayout();
} catch (ClassCastException exc) {
System.err.println("The first argument to makeCompactGrid must use SpringLayout.");
return;
}
//Align all cells in each column and make them the same width.
Spring x = Spring.constant(initialX);
for (int c = 0; c < cols; c++) {
Spring width = Spring.constant(0);
for (int r = 0; r < rows; r++) {
width = Spring.max(width,
getConstraintsForCell(r, c, parent, cols).
getWidth());
}
for (int r = 0; r < rows; r++) {
SpringLayout.Constraints constraints =
getConstraintsForCell(r, c, parent, cols);
constraints.setX(x);
constraints.setWidth(width);
}
x = Spring.sum(x, Spring.sum(width, Spring.constant(xPad)));
}
//Align all cells in each row and make them the same height.
Spring y = Spring.constant(initialY);
for (int r = 0; r < rows; r++) {
Spring height = Spring.constant(0);
for (int c = 0; c < cols; c++) {
height = Spring.max(height,
getConstraintsForCell(r, c, parent, cols).
getHeight());
}
for (int c = 0; c < cols; c++) {
SpringLayout.Constraints constraints =
getConstraintsForCell(r, c, parent, cols);
constraints.setY(y);
constraints.setHeight(height);
}
y = Spring.sum(y, Spring.sum(height, Spring.constant(yPad)));
}
//Set the parent's size.
SpringLayout.Constraints pCons = layout.getConstraints(parent);
pCons.setConstraint(SpringLayout.SOUTH, y);
pCons.setConstraint(SpringLayout.EAST, x);
}
}