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Swing CardLayout布局

CardLayout类排列卡的容器中的每个组件。在一个时间内只有一张卡是可见,与容器作为将整叠卡片。

类声明

以下是声明 java.awt.CardLayout类:

public class CardLayout
   extends Object
      implements LayoutManager2, Serializable

类构造函数

S.N. 构造函数 & 描述
1 CardLayout() 
Creates a new card layout with gaps of size zero.
2 CardLayout(int hgap, int vgap) 
Creates a new card layout with the specified horizontal and vertical gaps.

类方法

S.N. 方法 & 描述
1 void addLayoutComponent(Component comp, Object constraints) 
Adds the specified component to this card layout's internal table of names.
2 void addLayoutComponent(String name, Component comp) 
If the layout manager uses a per-component string, adds the component comp to the layout, associating it with the string specified by name.
3 void first(Container parent) 
Flips to the first card of the container.
4 int getHgap() 
Gets the horizontal gap between components.
5 float getLayoutAlignmentX(Container parent) 
Returns the alignment along the x axis.
6 float getLayoutAlignmentY(Container parent) 
Returns the alignment along the y axis.
7 int getVgap() 
Gets the vertical gap between components.
8 void invalidateLayout(Container target) 
Invalidates the layout, indicating that if the layout manager has cached information it should be discarded.
9 void last(Container parent) 
Flips to the last card of the container.
10 void layoutContainer(Container parent) 
Lays out the specified container using this card layout.
11 Dimension maximumLayoutSize(Container target) 
Returns the maximum dimensions for this layout given the components in the specified target container.
12 Dimension minimumLayoutSize(Container parent) 
Calculates the minimum size for the specified panel.
13 void next(Container parent) 
Flips to the next card of the specified container.
14 Dimension preferredLayoutSize(Container parent) 
Determines the preferred size of the container argument using this card layout.
15 void previous(Container parent) 
Flips to the previous card of the specified container.
16 void removeLayoutComponent(Component comp) 
Removes the specified component from the layout.
17 void setHgap(int hgap) 
Sets the horizontal gap between components.
18 void setVgap(int vgap) 
Sets the vertical gap between components.
19 void show(Container parent, String name) 
Flips to the component that was added to this layout with the specified name, using addLayoutComponent.
20 String toString() 
Returns a string representation of the state of this card layout.

方法继承

这个类从以下类继承的方法:

  • java.lang.Object

CardLayout 例子

选择使用任何编辑器创建以下java程序在 D:/ > SWING > com > yiibai > gui >

SwingLayoutDemo.java
package com.yiibai.gui;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class SwingLayoutDemo {
   private JFrame mainFrame;
   private JLabel headerLabel;
   private JLabel statusLabel;
   private JPanel controlPanel;
   private JLabel msglabel;

   public SwingLayoutDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      SwingLayoutDemo swingLayoutDemo = new SwingLayoutDemo();  
      swingLayoutDemo.showCardLayoutDemo();       
   }
      
   private void prepareGUI(){
      mainFrame = new JFrame("Java SWING Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));

      headerLabel = new JLabel("",JLabel.CENTER );
      statusLabel = new JLabel("",JLabel.CENTER);        

      statusLabel.setSize(350,100);
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
	        System.exit(0);
         }        
      });    
      controlPanel = new JPanel();
      controlPanel.setLayout(new FlowLayout());

      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }
   
   private void showCardLayoutDemo(){
      headerLabel.setText("Layout in action: CardLayout");      

      final JPanel panel = new JPanel();
      panel.setBackground(Color.CYAN);
      panel.setSize(300,300);

      CardLayout layout = new CardLayout();
      layout.setHgap(10);
      layout.setVgap(10);
      panel.setLayout(layout);        

      JPanel buttonPanel = new JPanel(new FlowLayout());

      buttonPanel.add(new JButton("OK"));
      buttonPanel.add(new JButton("Cancel"));    

      JPanel textBoxPanel = new JPanel(new FlowLayout());

      textBoxPanel.add(new JLabel("Name:"));
      textBoxPanel.add(new JTextField(20));

      panel.add("Button", buttonPanel);
      panel.add("Text", textBoxPanel);
      
	  final DefaultComboBoxModel panelName = new DefaultComboBoxModel();

      panelName.addElement("Button");
      panelName.addElement("Text");
     	  
	  final JComboBox listCombo = new JComboBox(panelName);    
      listCombo.setSelectedIndex(0);

      JScrollPane listComboScrollPane = new JScrollPane(listCombo);    

      JButton showButton = new JButton("Show");

      showButton.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) { 
            String data = "";
            if (listCombo.getSelectedIndex() != -1) {  
               CardLayout cardLayout = (CardLayout)(panel.getLayout());
               cardLayout.show(panel, 
               (String)listCombo.getItemAt(listCombo.getSelectedIndex()));	               
            }              
            statusLabel.setText(data);
         }
      }); 
	  
      controlPanel.add(listComboScrollPane);
      controlPanel.add(showButton);
	  controlPanel.add(panel);

      mainFrame.setVisible(true);  
   }
}

编译程序,使用命令提示符。到 D:/ > SWING 然后输出以下命令。

D:SWING>javac comyiibaiguiSwingLayoutDemo.java

如果没有错误出现,这意味着编译成功。使用下面的命令来运行程序。

D:SWING>java com.yiibai.gui.SwingLayoutDemo

验证下面的输出

SWING  CardLayout