第12章 轻量容器（续）

12.3.3 指定同一层中组件的位置

 

例12-7 同一层中放置组件的缺省方式

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

public class Test extends JApplet {
private JLayeredPane lp = new JLayeredPane();

private Integer[] layers = {
JLayeredPane.FRAME_CONTENT_LAYER,
JLayeredPane.DEFAULT_LAYER,
JLayeredPane.DEFAULT_LAYER,
JLayeredPane.DEFAULT_LAYER,
JLayeredPane.PALETTE_LAYER,
JLayeredPane.MODAL_LAYER,
JLayeredPane.POPUP_LAYER,
JLayeredPane.DRAG_LAYER,
};
private final Component[] comps = {
new JButton("Frame Content"), new JButton("Default"),
new JButton("default 1"), new JButton("default 2"),
new JButton("Palette"), new JButton("Modal"),
new JButton("Popup"), new JButton("Drag"),
};
public void init() {
setContentPane(lp);
lp.setLayout(null);

for(int i=0; i < comps.length; ++i) {
AbstractButton button = (AbstractButton)comps[i];

lp.setLayer(button, layers[i].intValue());
lp.add(button);
}
for(int i=0; i < comps.length; ++i) {
AbstractButton button = (AbstractButton)comps[i];
String t = button.getText();
String replacement = new String("Layer: ");

replacement += t + "(" + lp.getLayer(button) + "),";
replacement += " Index: " + lp.getIndexOf(button);
replacement += " Position: " +
lp.getPosition(button);

button.setText(replacement);
button.setBounds(i*50, i*50, 350, 75);
}
}
}

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例12-8 显式地设置同层中组件的位置

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

public class Test extends JApplet {
private JLayeredPane lp = new JLayeredPane();

private Integer[] layers = {
JLayeredPane.FRAME_CONTENT_LAYER,
JLayeredPane.DEFAULT_LAYER,
JLayeredPane.DEFAULT_LAYER,
JLayeredPane.DEFAULT_LAYER,
JLayeredPane.PALETTE_LAYER,
JLayeredPane.MODAL_LAYER,
JLayeredPane.POPUP_LAYER,
JLayeredPane.DRAG_LAYER,
};
private final Component[] comps = {
new JButton("Frame Content"), new JButton("Default"),
new JButton("default 1"), new JButton("default 2"),
new JButton("Palette"), new JButton("Modal"),
new JButton("Popup"), new JButton("Drag"),
};
public void init() {
setContentPane(lp);
lp.setLayout(null);

for(int i=0; i < comps.length; ++i) {
AbstractButton button = (AbstractButton)comps[i];
String t = button.getText();

lp.setLayer(button, layers[i].intValue());
lp.add(button);
}
for(int i=0; i < comps.length; ++i) {
AbstractButton button = (AbstractButton)comps[i];
String t = button.getText();
String replacement = new String("Layer: ");

if(t.equals("Default"))
lp.setPosition(button, 2);
else if(t.equals("default 2"))
lp.setPosition(button, 0);

replacement += t + "(" + lp.getLayer(button) + "),";
replacement += " Index: " + lp.getIndexOf(button);
replacement += " Position: " +
lp.getPosition(button);

button.setText(replacement);
button.setBounds(i*50, i*50, 350, 75);
}
}
}

---

 

 

12.3.4 使用拖动层

 

例12-9 使用拖动层

---

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

public class Test extends JApplet {
public void init() {
setContentPane(new CustomContentPane());
}
}
class CustomContentPane extends JLayeredPane {
private ImageIcon rain = new ImageIcon("rain.gif");
private ImageIcon punch = new ImageIcon("punch.gif");
private ImageIcon skelly = new ImageIcon("skelly.gif");
private int rainw = rain.getIconWidth();
private int rainh = rain.getIconHeight();

private JLabel[] labels = {
new JLabel("I stay put", punch, SwingConstants.RIGHT),
new JLabel("Drag me around!",
skelly, SwingConstants.RIGHT),
};

public CustomContentPane() {
Dragger listener = new Dragger();
JCheckBox onDragLayer = new JCheckBox("Drag Layer");

// JLayeredPane has a null layout by default
setLayout(new FlowLayout());

onDragLayer.setOpaque(false);

add(onDragLayer);
add(labels[0]);
add(labels[1]);

labels[1].addMouseMotionListener(listener);
labels[1].addMouseListener(listener);

setLabelText();

onDragLayer.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
if(e.getStateChange() == ItemEvent.SELECTED) {
setLayer(labels[1],
JLayeredPane.DRAG_LAYER.intValue());
}
else {
setLayer(labels[1],
JLayeredPane.DEFAULT_LAYER.intValue());

}
setLabelText();
validate();
}
});
}
public void paintComponent(Graphics g) {
Dimension size = getSize();

for(int row=0; row < size.height; row += rainh)
for(int col=0; col < size.width; col += rainw)
rain.paintIcon(this,g,col,row);
}
private void setLabelText() {
for(int i=0; i < labels.length; ++i) {
JLabel label = labels[i];
String t = new String("Layer: ");

t += "(" + getLayer(label) + "),";
t += " Index: " + getIndexOf(label);

label.setText(t);
}
}
}
class Dragger extends MouseAdapter
implements MouseMotionListener {
Point press = new Point();
boolean dragging = false;

public void mousePressed(MouseEvent event) {
press.x = event.getX();
press.y = event.getY();
dragging = true;
}
public boolean isDragging() {
return dragging;
}
public void mouseReleased(MouseEvent event) {
dragging = false;
}
public void mouseClicked(MouseEvent event) {
dragging = false;
}
public void mouseMoved(MouseEvent event) {
// don't care
}
public void mouseDragged(MouseEvent event) {
Component c = (Component)event.getSource();

if(dragging) {
Point loc = c.getLocation();
Point pt = new Point();
pt.x = event.getX() + loc.x - press.x;
pt.y = event.getY() + loc.y - press.y;
c.setLocation(pt.x, pt.y);
c.getParent().repaint();
}
}
}

---

12.3.5 JLayeredPane属性

 

12.3.6 JLayeredPane类总结

 

12.3.7 AWT兼容

 

12.4 JTablePane

 

例12-10 JTabbedPane的一个简单实例

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

public class Test extends JApplet {
public Test() {
Container contentPane = getContentPane();
JTabbedPane tp = new JTabbedPane();
JPanel panelOne = new JPanel();
JPanel panelTwo = new JPanel();

panelOne.add(new JButton("button in panel 1"));
panelTwo.add(new JButton("button in panel 2"));

tp.add(panelOne, "Panel One");
tp.addTab("Panel Two",
new ImageIcon("document.gif"),
panelTwo,
"tooltip text");

contentPane.setLayout(new BorderLayout());
contentPane.add(tp);
}
}

---

12.4.1 选项卡的位置

 

12.4.2 JTabbedPane的属性

 

例12-11 为JTabbedPane的实例设置选项卡放置位置

---

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

public class Test extends JApplet {
private JTabbedPane tp = new JTabbedPane(SwingConstants.BOTTOM);
private JComboBox combo = new JComboBox();

public Test() {
Container contentPane = getContentPane();
JPanel comboPanel = new JPanel();
JPanel panelOne = new JPanel();
JPanel panelTwo = new JPanel();

tp.add(panelOne, "Panel One");
tp.addTab("Panel Two",
new ImageIcon("document.gif"),
panelTwo,
"tooltip text");

combo.addItem("TOP");
combo.addItem("LEFT");
combo.addItem("RIGHT");
combo.addItem("BOTTOM");

setComboValue();

comboPanel.add(new JLabel("Tab Placement:"));
comboPanel.add(combo);

contentPane.setLayout(new BorderLayout());
contentPane.add(comboPanel, BorderLayout.NORTH);
contentPane.add(tp, BorderLayout.CENTER);

combo.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
JComboBox cb = (JComboBox)e.getSource();
int state = e.getStateChange();

if(state == ItemEvent.SELECTED) {
String s = (String)cb.getSelectedItem();

if(s.equals("TOP"))
tp.setTabPlacement(JTabbedPane.TOP);
else if(s.equals("LEFT"))
tp.setTabPlacement(JTabbedPane.LEFT);
else if(s.equals("RIGHT"))
tp.setTabPlacement(JTabbedPane.RIGHT);
else if(s.equals("BOTTOM"))
tp.setTabPlacement(JTabbedPane.BOTTOM);

tp.validate();
}
}
});
}
private void setComboValue() {
int placement = tp.getTabPlacement();
String selectedItem = null;

switch(placement) {
case JTabbedPane.TOP:
selectedItem = "TOP";
break;
case JTabbedPane.LEFT:
selectedItem = "LEFT";
break;
case JTabbedPane.RIGHT:
selectedItem = "RIGHT";
break;
case JTabbedPane.BOTTOM:
selectedItem = "BOTTOM";
break;
}
combo.setSelectedItem(selectedItem);
}
}

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12.4.3 JTabbedPane的事件

 

例12-12 响应JTabbedPane的变化事件

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

public class Test extends JApplet {

public Test() {
Container contentPane = getContentPane();
JTabbedPane tp = new JTabbedPane();
JPanel panelOne = new JPanel();
JPanel panelTwo = new JPanel();

tp.add(panelOne, "Panel One");
tp.addTab("Panel Two",
new ImageIcon("document.gif"),
panelTwo,
"tooltip text");

contentPane.setLayout(new BorderLayout());
contentPane.add(tp);

tp.addChangeListener(new ChangeListener() {
public void stateChanged(ChangeEvent e) {
JTabbedPane tabbedPane =
(JTabbedPane)e.getSource();

int index = tabbedPane.getSelectedIndex();
String s = tabbedPane.getTitleAt(index);

showStatus(s + " selected");
}
});
}
}

---

12.4.4 JTabbedPane类总结

 

12.5 JSplitPane类

 

例12-13 运行中的JSplitPane

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

public class Test extends JApplet {
public Test() {
Container contentPane = getContentPane();
JButton left, right;
JSplitPane sp = new JSplitPane();
ControlPanel cp = new ControlPanel(sp);

contentPane.setLayout(new BorderLayout());
contentPane.add(sp, BorderLayout.CENTER);
contentPane.add(cp, BorderLayout.NORTH);

left = (JButton)sp.getTopComponent();
right = (JButton)sp.getBottomComponent();

System.out.println("left button minimum size: " +
left.getMinimumSize());
System.out.println("right button minimum size: " +
right.getMinimumSize());

}
}

class ControlPanel extends JPanel {
private JSplitPane sp;

public ControlPanel(JSplitPane splitPane) {
sp = splitPane;

JComboBox dividerSize = new JComboBox();
JComboBox orientation = new JComboBox();

JCheckBox continuous = new JCheckBox(
"Continuous Layout");
JCheckBox oneTouch = new JCheckBox(
"One Touch Expandable");

Integer initialSize = new Integer(sp.getDividerSize());
dividerSize.addItem(initialSize.toString());
dividerSize.addItem("10");
dividerSize.addItem("20");
dividerSize.addItem("30");
dividerSize.addItem("40");

orientation.addItem("horizontal");
orientation.addItem("vertical");

int initialOrientation = sp.getOrientation();
if(initialOrientation == JSplitPane.HORIZONTAL_SPLIT)
orientation.setSelectedItem("horizontal");
else
orientation.setSelectedItem("vertical");

boolean initialContinuousLayout = sp.isContinuousLayout();
if(initialContinuousLayout)
continuous.setSelected(true);

add(oneTouch);
add(continuous);
add(new JLabel("Divider Size:"));
add(dividerSize);
add(new JLabel("Orientation:"));
add(orientation);

oneTouch.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
if(e.getStateChange() == ItemEvent.SELECTED)
sp.setOneTouchExpandable(true);
else
sp.setOneTouchExpandable(false);
}
});
continuous.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
if(e.getStateChange() == ItemEvent.SELECTED)
sp.setContinuousLayout(true);
else
sp.setContinuousLayout(false);
}
});
dividerSize.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
JComboBox combo = (JComboBox)e.getSource();
String s = (String)combo.getSelectedItem();

sp.setDividerSize(Integer.parseInt(s));
}
});
orientation.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent e) {
JComboBox combo = (JComboBox)e.getSource();
String s = (String)combo.getSelectedItem();

if(s.equals("horizontal"))
sp.setOrientation(
JSplitPane.HORIZONTAL_SPLIT);
else
sp.setOrientation(JSplitPane.VERTICAL_SPLIT);
}
});
}
}

---

12.5.1 JSplitPane属性

 

12.5.2 JSplitPane事件

 

例12-14 监视一个拆分窗格的分隔体的位置

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

public class Test extends JApplet {
public Test() {
Container contentPane = getContentPane();
JSplitPane sp = new JSplitPane();

contentPane.add(sp, BorderLayout.CENTER);
sp.addPropertyChangeListener(
new PropertyChangeListener() {
public void propertyChange(PropertyChangeEvent e) {
if(e.getPropertyName().equals(
JSplitPane.LAST_DIVIDER_LOCATION_PROPERTY)) {
JSplitPane jsp = (JSplitPane)e.getSource();

int dl = jsp.getDividerLocation();

JButton lb = (JButton)jsp.getLeftComponent();
JButton rb = (JButton)jsp.getRightComponent();

showStatus("Divider Location: " + dl + " / " +
lb.getText() + ": " + lb.getSize() + " / " +
rb.getText() + ": " + rb.getSize());
}
}
});
}
}

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12.5.3 JSplitPane类总结

 

12.5.4 AWT兼容

 

12.6 本章回顾