Java 网格布局重量错误?
我正在处理的项目中组件的布局看起来不正确,我怀疑Swing中存在错误。基本上,当布置的单元具有不同的最小尺寸和/或首选尺寸时,似乎发生的情况是,Java 网格布局重量错误?,java,swing,layout,grid,Java,Swing,Layout,Grid,我正在处理的项目中组件的布局看起来不正确,我怀疑Swing中存在错误。基本上,当布置的单元具有不同的最小尺寸和/或首选尺寸时,似乎发生的情况是,weightx和weighty比例没有得到遵守。我创建了一个示例程序来演示这一点,以下是源代码: package com.ensoftcorp.product.simmerge.gui.swing.dialogs; import java.awt.Color; import java.awt.Dimension; import java.awt.Gri
weightx
和weighty
比例没有得到遵守。我创建了一个示例程序来演示这一点,以下是源代码:
package com.ensoftcorp.product.simmerge.gui.swing.dialogs;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import javax.swing.BorderFactory;
import javax.swing.Box;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class TestClass {
/**
* @param args
*/
public static void main(String[] args) {
try {
//UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
new TestClass();
} catch (Exception e) {
e.printStackTrace();
}
}
static final GridBagConstraints GBC_CELL = new GridBagConstraints();
static final GridBagConstraints GBC_ROWEND = new GridBagConstraints();
static final GridBagConstraints GBC_FILLROW = new GridBagConstraints();
static {
GBC_CELL.anchor = GridBagConstraints.NORTHWEST;
GBC_CELL.weightx = 0.5;
GBC_CELL.fill = GridBagConstraints.BOTH;
GBC_ROWEND.gridwidth = GridBagConstraints.REMAINDER;
GBC_FILLROW.gridwidth = GridBagConstraints.REMAINDER;
GBC_FILLROW.weightx = 1.0;
GBC_FILLROW.fill = GridBagConstraints.BOTH;
}
public TestClass() {
JFrame frame = new JFrame();
JPanel pnlContent = new JPanel(new GridBagLayout());
pnlContent.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
/*
* Layout "ruler" panel
*/
JPanel pnlRuler = new JPanel(new GridBagLayout());
pnlRuler.add(createRulerCell(Color.BLACK, Color.WHITE),GBC_CELL);
pnlRuler.add(createRulerCell(Color.BLACK, Color.WHITE),GBC_CELL);
pnlRuler.add(Box.createHorizontalGlue(),GBC_ROWEND);
/*
* Layout "correct" panel
*/
JPanel pnlGoodLayout = new JPanel(new GridBagLayout());
pnlGoodLayout.add(new JButton("JButton1"),GBC_CELL);
pnlGoodLayout.add(new JButton("JButton2"),GBC_CELL);
pnlGoodLayout.add(Box.createHorizontalGlue(),GBC_ROWEND);
pnlGoodLayout.add(new JButton("JButton3"),GBC_CELL);
pnlGoodLayout.add(new JButton("JButton4"),GBC_CELL);
pnlGoodLayout.add(Box.createHorizontalGlue(),GBC_ROWEND);
/*
* Layout "incorrect" panel
*/
JPanel pnlBadLayout = new JPanel(new GridBagLayout());
pnlBadLayout.add(new JButton("JButton1"),GBC_CELL);
pnlBadLayout.add(new JButton("JButton2"),GBC_CELL);
pnlBadLayout.add(Box.createHorizontalGlue(),GBC_ROWEND);
pnlBadLayout.add(new JButton("JButton number 3 is wide"),GBC_CELL);
pnlBadLayout.add(new JButton("JButton4"),GBC_CELL);
pnlBadLayout.add(Box.createHorizontalGlue(),GBC_ROWEND);
/*
* Add panels to main panel
*/
pnlContent.add(pnlRuler,GBC_FILLROW);
pnlContent.add(Box.createVerticalStrut(8),GBC_FILLROW);
pnlContent.add(pnlGoodLayout,GBC_FILLROW);
pnlContent.add(Box.createVerticalStrut(8),GBC_FILLROW);
pnlContent.add(pnlBadLayout,GBC_FILLROW);
/*
* Configure frame
*/
frame.getContentPane().add(pnlContent);
frame.setTitle("GridBagLayout Weight Bug?");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400,200);
frame.setVisible(true);
}
JComponent createRulerCell(Color border, Color background) {
JPanel glue = new JPanel();
glue.setBorder(BorderFactory.createLineBorder(border));
glue.setBackground(background);
return glue;
}
}
示例程序有三组…第一组是显示50%分数的“标尺”。第二组和第三组是使用GridBagLayout的面板,其中每个单元格的权重x为0.5。这两个组之间的唯一区别是按钮文本长度,但是第二个组的列比例并不均匀,即使它有足够的空间这样做
我的问题是:以前有没有人遇到过这个问题,他们会推荐一种解决方法
附言——如果jdk1.6.0_11有区别的话,我正在使用它。来自:
指定如何分配额外的水平空间
网格行李布局管理器将列的重量计算为列中所有组件的最大重量X。如果生成的布局在水平方向上小于需要填充的区域,则额外的空间将按其权重比例分配给每列
考虑到这一点,我不认为这是一个bug,因为带有wide按钮的列需要更多的空间。一旦计算了该值和正常按钮列的大小,剩余的空间将被分配
解决方法:
要解决此问题,可以在添加每个按钮之前设置GBC_CELL.gridx
和GBC_CELL.gridy
,在与大按钮共享行的按钮之前,可以设置
GBC_单元,ipadx=100代码>
然后将其设置为0
,然后再添加宽按钮(#3)。这将使按钮在更多的网格中对齐。使用内置按钮。您拥有比GridBagLayout更多的控制权。这可能会有帮助:
当多个列具有非零权重时,多余的空间为
使用权重值分布在非零权重列中。
特别是,如果多余空间为P个像素,则列权重
因为列^i是权重^i,那么列^i得到的正好是(权重^i*P)/
(所有列权重之和)。例如,如果列1的权重为1
列2的权重为2,多余空间为90像素,列1
将获得30个额外像素,第2列将获得60个额外像素。排
对于非零权重,其行为方式类似
我找到了一个简单的解决办法。将每个JButton
的preferredSize.width
属性显式设置为preferredSize.width=0
这是一种方法:
private JButton createButton(String text) {
JButton button = new JButton(text);
button.setPreferredSize(new Dimension(0, button.getPreferredSize().height));
return button;
}
这是您修改过的示例(我用//
public class TestClass {
/**
* @param args
*/
public static void main(String[] args) {
try {
//UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
new TestClass();
} catch (Exception e) {
e.printStackTrace();
}
}
static final GridBagConstraints GBC_CELL = new GridBagConstraints();
static final GridBagConstraints GBC_ROWEND = new GridBagConstraints();
static final GridBagConstraints GBC_FILLROW = new GridBagConstraints();
static {
GBC_CELL.anchor = GridBagConstraints.NORTHWEST;
GBC_CELL.weightx = 0.5;
GBC_CELL.fill = GridBagConstraints.BOTH;
GBC_ROWEND.gridwidth = GridBagConstraints.REMAINDER;
GBC_FILLROW.gridwidth = GridBagConstraints.REMAINDER;
GBC_FILLROW.weightx = 1.0;
GBC_FILLROW.fill = GridBagConstraints.BOTH;
}
public TestClass() {
JFrame frame = new JFrame();
JPanel pnlContent = new JPanel(new GridBagLayout());
pnlContent.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
/*
* Layout "ruler" panel
*/
JPanel pnlRuler = new JPanel(new GridBagLayout());
pnlRuler.add(createRulerCell(Color.BLACK, Color.WHITE),GBC_CELL);
pnlRuler.add(createRulerCell(Color.BLACK, Color.WHITE),GBC_CELL);
pnlRuler.add(Box.createHorizontalGlue(),GBC_ROWEND);
/*
* Layout "correct" panel
*/
JPanel pnlGoodLayout = new JPanel(new GridBagLayout());
pnlGoodLayout.add(createButton("JButton1"),GBC_CELL); // <==============
pnlGoodLayout.add(createButton("JButton2"),GBC_CELL); // <==============
pnlGoodLayout.add(Box.createHorizontalGlue(),GBC_ROWEND);
pnlGoodLayout.add(createButton("JButton3"),GBC_CELL); // <==============
pnlGoodLayout.add(createButton("JButton4"),GBC_CELL); // <==============
pnlGoodLayout.add(Box.createHorizontalGlue(),GBC_ROWEND);
/*
* Layout "incorrect" panel
*/
JPanel pnlBadLayout = new JPanel(new GridBagLayout());
pnlBadLayout.add(createButton("JButton1"),GBC_CELL); // <==============
pnlBadLayout.add(createButton("JButton2"),GBC_CELL); // <==============
pnlBadLayout.add(Box.createHorizontalGlue(),GBC_ROWEND);
pnlBadLayout.add(createButton("JButton number 3 is wide"),GBC_CELL); // <==============
pnlBadLayout.add(createButton("JButton4"),GBC_CELL); // <==============
pnlBadLayout.add(Box.createHorizontalGlue(),GBC_ROWEND);
/*
* Add panels to main panel
*/
pnlContent.add(pnlRuler,GBC_FILLROW);
pnlContent.add(Box.createVerticalStrut(8),GBC_FILLROW);
pnlContent.add(pnlGoodLayout,GBC_FILLROW);
pnlContent.add(Box.createVerticalStrut(8),GBC_FILLROW);
pnlContent.add(pnlBadLayout,GBC_FILLROW);
/*
* Configure frame
*/
frame.getContentPane().add(pnlContent);
frame.setTitle("GridBagLayout Weight Bug?");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(400,200);
frame.setVisible(true);
}
JComponent createRulerCell(Color border, Color background) {
JPanel glue = new JPanel();
glue.setBorder(BorderFactory.createLineBorder(border));
glue.setBackground(background);
return glue;
}
private JButton createButton(String text) {
JButton button = new JButton(text);
button.setPreferredSize(new Dimension(0, button.getPreferredSize().height));
return button;
}
}