Java 如何防止在JTabbedPane上留下选项卡
我有一个应用程序，它有嵌套的JTabbedPane。每个JTabbedPane包括其他JTabbedPane 我想在允许用户离开当前选项卡之前检查一些内容 当您运行下面的代码时，您将看到月份->二月选项卡有一个允许复选框 如果选中“允许”复选框，则我希望允许用户导航以离开当前面板。如果不是，那么他们不能离开，直到它 在显示下一个组件（可能在另一个JTabbedPane上）之前，我似乎找不到处理离开请求的方法 这可以通过转到月份->二月选项卡，然后选择颜色选项卡来演示 有什么想法吗Java 如何防止在JTabbedPane上留下选项卡,java,swing,jtabbedpane,Java,Swing,Jtabbedpane,我有一个应用程序，它有嵌套的JTabbedPane。每个JTabbedPane包括其他JTabbedPane 我想在允许用户离开当前选项卡之前检查一些内容 当您运行下面的代码时，您将看到月份->二月选项卡有一个允许复选框 如果选中“允许”复选框，则我希望允许用户导航以离开当前面板。如果不是，那么他们不能离开，直到它 在显示下一个组件（可能在另一个JTabbedPane上）之前，我似乎找不到处理离开请求的方法 这可以通过转到月份->二月选项卡，然后选择颜色选项卡来演示 有什么想法吗 import
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.HierarchyEvent;
import java.awt.event.HierarchyListener;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.SwingUtilities;
public class VerifyBeforeLeavingTab extends JFrame
{
private static final long serialVersionUID = 1L;
public VerifyBeforeLeavingTab()
{
setSize(700, 700);
JTabbedPane mainTabbedPane = new JTabbedPane(JTabbedPane.TOP);
MyJTabbedPane colorsPane = new MyJTabbedPane(JTabbedPane.TOP, "colors");
JPanel bluePanel = new JPanel();
bluePanel.setBackground(Color.blue);
colorsPane.addTab("Blue", bluePanel);
JPanel redPanel = new JPanel();
redPanel.setBackground(Color.red);
colorsPane.addTab("Red", redPanel);
mainTabbedPane.addTab("Colors", colorsPane);
JTabbedPane monthsPane = new MyJTabbedPane(JTabbedPane.TOP, "months");
JPanel janPanel = new JPanel();
monthsPane.addTab("January", janPanel);
JPanel febPanel = new MyUnleavableJPanel();
monthsPane.addTab("February", febPanel);
mainTabbedPane.addTab("Months", monthsPane);
add(mainTabbedPane, BorderLayout.CENTER);
getContentPane().add(mainTabbedPane);
}
private class MyUnleavableJPanel extends JPanel
{
private static final long serialVersionUID = 1L;
public MyUnleavableJPanel()
{
final JCheckBox chckBoxAllowToLeave = new JCheckBox("Allow to leave");
chckBoxAllowToLeave.setBounds(100, 100, 50, 50);
this.add(chckBoxAllowToLeave);
addHierarchyListener(new HierarchyListener()
{
public void hierarchyChanged(HierarchyEvent e)
{
if ((HierarchyEvent.SHOWING_CHANGED & e.getChangeFlags()) != 0)
{
if (isShowing())
{
System.out.println("Showing an unleavable panel");
}
else
{
// TODO: Do not let them leave this JCheckbox is selected
if (chckBoxAllowToLeave.isSelected())
{
System.out.println("OK to leave");
}
else
{
System.out.println("Not allowed to leave");
}
}
}
}
});
}
}
private class MyJTabbedPane extends JTabbedPane
{
private static final long serialVersionUID = 1L;
public MyJTabbedPane(int i, String name)
{
super(i);
setName(name);
}
@Override
public void setSelectedIndex(int index)
{
System.out.println("Now on '" + getName() + "' tab #" + index);
super.setSelectedIndex(index);
}
}
private static void createAndShowGUI()
{
// Create and set up the window.
VerifyBeforeLeavingTab frame = new VerifyBeforeLeavingTab();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
try
{
createAndShowGUI();
}
catch (Exception e)
{
e.printStackTrace();
System.exit(0);
}
}
});
}
}
我扩展了JTabbedPane并重写了setSelectedIndex（）。如果要允许选择成功，请调用super.setSelectedIndex；否则不要
我使用它调用与该选项卡关联的验证例程，如果验证失败，则否决更改。这种方法的一个优点是，它完全不依赖于用户如何更改选项卡——他可以单击选项卡，单击移动选项卡的按钮，等等。我扩展了JTabbedPane并覆盖了setSelectedIndex（）。如果要允许选择成功，请调用super.setSelectedIndex；否则不要
我使用它调用与该选项卡关联的验证例程，如果验证失败，则否决更改。这种方法的一个优点是，它完全不依赖于用户如何更改选项卡——他可以单击选项卡，单击移动选项卡的按钮，等等。好的，决定继续我自己的示例；两个类，运行main类会生成一个swing窗口，允许您每隔单击一次就更改选项卡
import javax.swing.JFrame;
import javax.swing.JPanel;
public class TabbedPaneExample extends JFrame
{
public static void main(String[] args)
{
TabbedPaneExample example = new TabbedPaneExample();
example.go();
}
public void go()
{
ValidatingTabbedPane vtp = new ValidatingTabbedPane();
for(int i=0; i<3; i++)
{
vtp.addTab(""+i, new JPanel());
}
vtp.setSelectedIndex(0);
getContentPane().add(vtp);
pack();
setVisible(true);
}
}
import javax.swing.JFrame；
导入javax.swing.JPanel；
公共类TabbedPaneeExample扩展了JFrame
{
公共静态void main（字符串[]args）
{
TabbedPaneExample example=new TabbedPaneExample（）；
例如：go（）；
}
公开作废go（）
{
ValidatingAbbedPane vtp=新的ValidatingAbbedPane（）；
对于（int i=0；i=0&&newIndex我在中留下了注释，以显示我在实际程序中验证的位置。好的，决定继续我自己的示例；两个类，运行main类会生成一个swing窗口，允许您每隔单击一次就更改选项卡
import javax.swing.JFrame;
import javax.swing.JPanel;
public class TabbedPaneExample extends JFrame
{
public static void main(String[] args)
{
TabbedPaneExample example = new TabbedPaneExample();
example.go();
}
public void go()
{
ValidatingTabbedPane vtp = new ValidatingTabbedPane();
for(int i=0; i<3; i++)
{
vtp.addTab(""+i, new JPanel());
}
vtp.setSelectedIndex(0);
getContentPane().add(vtp);
pack();
setVisible(true);
}
}
import javax.swing.JFrame；
导入javax.swing.JPanel；
公共类TabbedPaneeExample扩展了JFrame
{
公共静态void main（字符串[]args）
{
TabbedPaneExample example=new TabbedPaneExample（）；
例如：go（）；
}
公开作废go（）
{
ValidatingAbbedPane vtp=新的ValidatingAbbedPane（）；
对于（int i=0；i=0&&newIndex我在中留下了注释，以显示我在实际程序中验证的位置。@rcook-我已将您的setSelected（）方法插入到我的原始代码中。 运行程序时，将显示蓝色面板（在“颜色”选项卡下） 如果你去二月的小组（在任务单下）
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.HierarchyEvent;
import java.awt.event.HierarchyListener;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.SwingUtilities;
public class VerifyBeforeLeavingTab extends JFrame
{
private static final long serialVersionUID = 1L;
private static final JCheckBox chckBoxAllowToLeave = new JCheckBox("Allow to leave");
public VerifyBeforeLeavingTab()
{
setSize(700, 700);
JTabbedPane mainTabbedPane = new JTabbedPane(JTabbedPane.TOP);
MyJTabbedPane colorsPane = new MyJTabbedPane(JTabbedPane.TOP, "colors");
JPanel bluePanel = new JPanel();
bluePanel.setBackground(Color.blue);
colorsPane.addTab("Blue", bluePanel);
JPanel redPanel = new JPanel();
redPanel.setBackground(Color.red);
colorsPane.addTab("Red", redPanel);
mainTabbedPane.addTab("Colors", colorsPane);
JTabbedPane monthsPane = new MyJTabbedPane(JTabbedPane.TOP, "months");
JPanel janPanel = new JPanel();
monthsPane.addTab("January", janPanel);
JPanel febPanel = new MyUnleavableJPanel();
monthsPane.addTab("February", febPanel);
mainTabbedPane.addTab("Months", monthsPane);
add(mainTabbedPane, BorderLayout.CENTER);
getContentPane().add(mainTabbedPane);
}
private class MyUnleavableJPanel extends JPanel
{
private static final long serialVersionUID = 1L;
public MyUnleavableJPanel()
{
// final JCheckBox chckBoxAllowToLeave = new JCheckBox("Allow to leave");
chckBoxAllowToLeave.setBounds(100, 100, 50, 50);
chckBoxAllowToLeave.setSelected(true);
this.add(chckBoxAllowToLeave);
addHierarchyListener(new HierarchyListener()
{
public void hierarchyChanged(HierarchyEvent e)
{
if ((HierarchyEvent.SHOWING_CHANGED & e.getChangeFlags()) != 0)
{
if (isShowing())
{
System.out.println("Showing an unleavable panel");
}
else
{
// TODO: Do not let them leave if this JCheckbox is selected
if (chckBoxAllowToLeave.isSelected())
{
System.out.println("OK to leave");
}
else
{
System.out.println("Not allowed to leave");
}
}
}
}
});
}
}
private class MyJTabbedPane extends JTabbedPane
{
private static final long serialVersionUID = 1L;
public MyJTabbedPane(int i, String name)
{
super(i);
setName(name);
}
/**
* override of selecting a new panel; the new panel selection is only allowed after the current panel determines
* that its data is valid.
*/
@Override
public void setSelectedIndex(int newIndex)
{
System.out.println("Now on '" + getName() + "' tab #" + newIndex);
int currentIndex = getSelectedIndex();
if (newIndex >= 0 && newIndex < getTabCount())
{
// if we are currently setting the selected tab for the first
// time, we don't need to validate the currently selected panel;
// same if we're (somehow) selecting the current panel
if (currentIndex == -1)
{
super.setSelectedIndex(newIndex);
}
else
{
if (currentIndex != newIndex)
{
if (chckBoxAllowToLeave.isSelected())
{
super.setSelectedIndex(newIndex);
}
else
{
JOptionPane.showMessageDialog(null, "Not this time");
}
}
}
}
else
{
System.out.println("setting new tabbed pane index to " + newIndex + "; wonder why?");
}
}
}
private static void createAndShowGUI()
{
// Create and set up the window.
VerifyBeforeLeavingTab frame = new VerifyBeforeLeavingTab();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
public static void main(String[] args)
{
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
try
{
createAndShowGUI();
}
catch (Exception e)
{
e.printStackTrace();
System.exit(0);
}
}
});
}
}