前两天看到了关于面板收缩与展开的实例,现在有几个疑问想请教各位高手:1、我要写一个BordeLayout的主程序,想把面板收缩与展开的部分布局在西侧,但不知如何调用这个程序,应该怎么处理??
2、程序中“level 1"等文字是绘图上去的,但是怎么才能把它们居中呢?
3、如何点击面板的任意部位都可收缩或展开面板,而不仅局限在三角型区域呢??
源程序如下:
import java.awt.*;
import java.awt.event.*;
import java.awt.font.*;
import java.awt.image.BufferedImage;
import javax.swing.*; public class ExpandingPanels extends MouseAdapter {
ActionPanel[] aps;
JPanel[] panels; public ExpandingPanels() {
assembleActionPanels();
assemblePanels();
} public void mousePressed(MouseEvent e) {
ActionPanel ap = (ActionPanel) e.getSource();
if (ap.target.contains(e.getPoint())) {
ap.toggleSelection();
togglePanelVisibility(ap);
}
} private void togglePanelVisibility(ActionPanel ap) {
int index = getPanelIndex(ap);
if (panels[index].isShowing())
panels[index].setVisible(false);
else
panels[index].setVisible(true);
ap.getParent().validate();
} private int getPanelIndex(ActionPanel ap) {
for (int j = 0; j < aps.length; j++)
if (ap == aps[j])
return j;
return -1;
} private void assembleActionPanels() {
String[] ids = { "level 1", "level 2", "level 3", "level 4" };
aps = new ActionPanel[ids.length];
for (int j = 0; j < aps.length; j++)
aps[j] = new ActionPanel(ids[j], this);
} private void assemblePanels() {
GridBagConstraints gbc = new GridBagConstraints();
gbc.insets = new Insets(2, 1, 2, 1);
gbc.weightx = 1.0;
gbc.weighty = 1.0;
JPanel p1 = new JPanel(new GridBagLayout());
gbc.gridwidth = gbc.RELATIVE;
p1.add(new JButton("button 1"), gbc);
gbc.gridwidth = gbc.REMAINDER;
p1.add(new JButton("button 2"), gbc);
gbc.gridwidth = gbc.RELATIVE;
p1.add(new JButton("button 3"), gbc);
gbc.gridwidth = gbc.REMAINDER;
p1.add(new JButton("button 4"), gbc);
JPanel p2 = new JPanel(new GridBagLayout());
gbc.gridwidth = 1;
gbc.anchor = gbc.EAST;
p2.add(new JLabel("enter"), gbc);
gbc.anchor = gbc.WEST;
p2.add(new JTextField(8), gbc);
gbc.anchor = gbc.CENTER;
p2.add(new JButton("button 1"), gbc);
gbc.gridwidth = gbc.REMAINDER;
p2.add(new JButton("button 2"), gbc);
JPanel p3 = new JPanel(new BorderLayout());
JTextArea textArea = new JTextArea(8, 12);
textArea.setLineWrap(true);
p3.add(new JScrollPane(textArea));
JPanel p4 = new JPanel(new GridBagLayout());
addComponents(new JLabel("label 1"), new JTextField(12), p4, gbc);
addComponents(new JLabel("label 2"), new JTextField(16), p4, gbc);
gbc.gridwidth = 2;
gbc.gridy = 2;
p4.add(new JSlider(), gbc);
gbc.gridy++;
JPanel p5 = new JPanel(new GridBagLayout());
p5.add(new JButton("button 1"), gbc);
p5.add(new JButton("button 2"), gbc);
p5.add(new JButton("button 3"), gbc);
p5.add(new JButton("button 4"), gbc);
gbc.weighty = 1.0;
gbc.fill = gbc.BOTH;
p4.add(p5, gbc);
panels = new JPanel[] { p1, p2, p3, p4 };
} private void addComponents(Component c1, Component c2, Container c,
GridBagConstraints gbc) {
gbc.anchor = gbc.EAST;
gbc.gridwidth = gbc.RELATIVE;
c.add(c1, gbc);
gbc.anchor = gbc.WEST;
gbc.gridwidth = gbc.REMAINDER;
c.add(c2, gbc);
gbc.anchor = gbc.CENTER;
} private JPanel getComponent() {
JPanel panel = new JPanel(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.insets = new Insets(1, 3, 0, 3);
gbc.weightx = 1.0;
gbc.fill = gbc.HORIZONTAL;
gbc.gridwidth = gbc.REMAINDER;
for (int j = 0; j < aps.length; j++) {
panel.add(aps[j], gbc);
panel.add(panels[j], gbc);
panels[j].setVisible(false);
}
JLabel padding = new JLabel();
gbc.weighty = 1.0;
panel.add(padding, gbc);
return panel;
} public static void main(String[] args) {
ExpandingPanels test = new ExpandingPanels();
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.getContentPane().add(new JScrollPane(test.getComponent()));
f.setSize(360, 500);
f.setLocation(200, 100);
f.setVisible(true);
}
} class ActionPanel extends JPanel {
String text;
Font font;
private boolean selected;
BufferedImage open, closed;
Rectangle target;
final int OFFSET = 30, PAD = 5; public ActionPanel(String text, MouseListener ml) {
this.text = text;
addMouseListener(ml);
font = new Font("sans-serif", Font.PLAIN, 12);
selected = false;
setBackground(new Color(200, 200, 220));
setPreferredSize(new Dimension(200, 20));
setBorder(BorderFactory.createRaisedBevelBorder());
setPreferredSize(new Dimension(200, 20));
createImages();
setRequestFocusEnabled(true);
} public void toggleSelection() {
selected = !selected;
repaint();
} protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
int w = getWidth();
int h = getHeight();
if (selected)
g2.drawImage(open, PAD, 0, this);
else
g2.drawImage(closed, PAD, 0, this);
g2.setFont(font);
FontRenderContext frc = g2.getFontRenderContext();
LineMetrics lm = font.getLineMetrics(text, frc);
float height = lm.getAscent() + lm.getDescent();
float x = OFFSET;
float y = (h + height) / 2 - lm.getDescent();
g2.drawString(text, x, y);
} private void createImages() {
int w = 20;
int h = getPreferredSize().height;
target = new Rectangle(2, 0, 20, 18);
open = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = open.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setPaint(getBackground());
g2.fillRect(0, 0, w, h);
int[] x = { 2, w / 2, 18 };
int[] y = { 4, 15, 4 };
Polygon p = new Polygon(x, y, 3);
g2.setPaint(Color.green.brighter());
g2.fill(p);
g2.setPaint(Color.blue.brighter());
g2.draw(p);
g2.dispose();
closed = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
g2 = closed.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setPaint(getBackground());
g2.fillRect(0, 0, w, h);
x = new int[] { 3, 13, 3 };
y = new int[] { 4, h / 2, 16 };
p = new Polygon(x, y, 3);
g2.setPaint(Color.red);
g2.fill(p);
g2.setPaint(Color.blue.brighter());
g2.draw(p);
g2.dispose();
}
}
2、程序中“level 1"等文字是绘图上去的,但是怎么才能把它们居中呢?
3、如何点击面板的任意部位都可收缩或展开面板,而不仅局限在三角型区域呢??
源程序如下:
import java.awt.*;
import java.awt.event.*;
import java.awt.font.*;
import java.awt.image.BufferedImage;
import javax.swing.*; public class ExpandingPanels extends MouseAdapter {
ActionPanel[] aps;
JPanel[] panels; public ExpandingPanels() {
assembleActionPanels();
assemblePanels();
} public void mousePressed(MouseEvent e) {
ActionPanel ap = (ActionPanel) e.getSource();
if (ap.target.contains(e.getPoint())) {
ap.toggleSelection();
togglePanelVisibility(ap);
}
} private void togglePanelVisibility(ActionPanel ap) {
int index = getPanelIndex(ap);
if (panels[index].isShowing())
panels[index].setVisible(false);
else
panels[index].setVisible(true);
ap.getParent().validate();
} private int getPanelIndex(ActionPanel ap) {
for (int j = 0; j < aps.length; j++)
if (ap == aps[j])
return j;
return -1;
} private void assembleActionPanels() {
String[] ids = { "level 1", "level 2", "level 3", "level 4" };
aps = new ActionPanel[ids.length];
for (int j = 0; j < aps.length; j++)
aps[j] = new ActionPanel(ids[j], this);
} private void assemblePanels() {
GridBagConstraints gbc = new GridBagConstraints();
gbc.insets = new Insets(2, 1, 2, 1);
gbc.weightx = 1.0;
gbc.weighty = 1.0;
JPanel p1 = new JPanel(new GridBagLayout());
gbc.gridwidth = gbc.RELATIVE;
p1.add(new JButton("button 1"), gbc);
gbc.gridwidth = gbc.REMAINDER;
p1.add(new JButton("button 2"), gbc);
gbc.gridwidth = gbc.RELATIVE;
p1.add(new JButton("button 3"), gbc);
gbc.gridwidth = gbc.REMAINDER;
p1.add(new JButton("button 4"), gbc);
JPanel p2 = new JPanel(new GridBagLayout());
gbc.gridwidth = 1;
gbc.anchor = gbc.EAST;
p2.add(new JLabel("enter"), gbc);
gbc.anchor = gbc.WEST;
p2.add(new JTextField(8), gbc);
gbc.anchor = gbc.CENTER;
p2.add(new JButton("button 1"), gbc);
gbc.gridwidth = gbc.REMAINDER;
p2.add(new JButton("button 2"), gbc);
JPanel p3 = new JPanel(new BorderLayout());
JTextArea textArea = new JTextArea(8, 12);
textArea.setLineWrap(true);
p3.add(new JScrollPane(textArea));
JPanel p4 = new JPanel(new GridBagLayout());
addComponents(new JLabel("label 1"), new JTextField(12), p4, gbc);
addComponents(new JLabel("label 2"), new JTextField(16), p4, gbc);
gbc.gridwidth = 2;
gbc.gridy = 2;
p4.add(new JSlider(), gbc);
gbc.gridy++;
JPanel p5 = new JPanel(new GridBagLayout());
p5.add(new JButton("button 1"), gbc);
p5.add(new JButton("button 2"), gbc);
p5.add(new JButton("button 3"), gbc);
p5.add(new JButton("button 4"), gbc);
gbc.weighty = 1.0;
gbc.fill = gbc.BOTH;
p4.add(p5, gbc);
panels = new JPanel[] { p1, p2, p3, p4 };
} private void addComponents(Component c1, Component c2, Container c,
GridBagConstraints gbc) {
gbc.anchor = gbc.EAST;
gbc.gridwidth = gbc.RELATIVE;
c.add(c1, gbc);
gbc.anchor = gbc.WEST;
gbc.gridwidth = gbc.REMAINDER;
c.add(c2, gbc);
gbc.anchor = gbc.CENTER;
} private JPanel getComponent() {
JPanel panel = new JPanel(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
gbc.insets = new Insets(1, 3, 0, 3);
gbc.weightx = 1.0;
gbc.fill = gbc.HORIZONTAL;
gbc.gridwidth = gbc.REMAINDER;
for (int j = 0; j < aps.length; j++) {
panel.add(aps[j], gbc);
panel.add(panels[j], gbc);
panels[j].setVisible(false);
}
JLabel padding = new JLabel();
gbc.weighty = 1.0;
panel.add(padding, gbc);
return panel;
} public static void main(String[] args) {
ExpandingPanels test = new ExpandingPanels();
JFrame f = new JFrame();
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.getContentPane().add(new JScrollPane(test.getComponent()));
f.setSize(360, 500);
f.setLocation(200, 100);
f.setVisible(true);
}
} class ActionPanel extends JPanel {
String text;
Font font;
private boolean selected;
BufferedImage open, closed;
Rectangle target;
final int OFFSET = 30, PAD = 5; public ActionPanel(String text, MouseListener ml) {
this.text = text;
addMouseListener(ml);
font = new Font("sans-serif", Font.PLAIN, 12);
selected = false;
setBackground(new Color(200, 200, 220));
setPreferredSize(new Dimension(200, 20));
setBorder(BorderFactory.createRaisedBevelBorder());
setPreferredSize(new Dimension(200, 20));
createImages();
setRequestFocusEnabled(true);
} public void toggleSelection() {
selected = !selected;
repaint();
} protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
int w = getWidth();
int h = getHeight();
if (selected)
g2.drawImage(open, PAD, 0, this);
else
g2.drawImage(closed, PAD, 0, this);
g2.setFont(font);
FontRenderContext frc = g2.getFontRenderContext();
LineMetrics lm = font.getLineMetrics(text, frc);
float height = lm.getAscent() + lm.getDescent();
float x = OFFSET;
float y = (h + height) / 2 - lm.getDescent();
g2.drawString(text, x, y);
} private void createImages() {
int w = 20;
int h = getPreferredSize().height;
target = new Rectangle(2, 0, 20, 18);
open = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = open.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setPaint(getBackground());
g2.fillRect(0, 0, w, h);
int[] x = { 2, w / 2, 18 };
int[] y = { 4, 15, 4 };
Polygon p = new Polygon(x, y, 3);
g2.setPaint(Color.green.brighter());
g2.fill(p);
g2.setPaint(Color.blue.brighter());
g2.draw(p);
g2.dispose();
closed = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
g2 = closed.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setPaint(getBackground());
g2.fillRect(0, 0, w, h);
x = new int[] { 3, 13, 3 };
y = new int[] { 4, h / 2, 16 };
p = new Polygon(x, y, 3);
g2.setPaint(Color.red);
g2.fill(p);
g2.setPaint(Color.blue.brighter());
g2.draw(p);
g2.dispose();
}
}
2.final int OFFSET = 30, PAD = 5; 把offset的值變大就行了~
3.target = new Rectangle(2, 0, 20, 18); 把里面的后兩個坐標值變大 就行了
能提供个源码不?简单点的就行
2、改变offset的值是可以,但不一定恰取到能居中的值,一个一个试不现实吧?!有其他方法吗??
问题1:
先把private JPanel getComponent()改成public
在你的frame的mainPanel中,用mainPanel.add(new JScrollPane(leftPanel.getComponent()),BorderLayout.WEST);
leftPanel就是ExpandingPanels
这个程序是把ActivePanel的内容绘制上去的,其实不用也可以,
你可以把paintComponent方法注释掉
ActionPanel的构造函数修改成:
setPreferredSize(new Dimension(200, 30));
this.add(new JLabel(text));
//createImages();
然后,mousePressed的内容稍微修改下:
ap.contains(e.getPoint())
问题3:问题2的修改就解决了问题3。
问题4:我要实现面板中各组件的事件响应,是要在你的这个程序里添加把?
如果是现在的这个类的话,你要修改的地方还有好多
并且把ActivePanel展开后的Panel作为ActivePanel的一个引用,最好在保持一个
类似如JFrame这样的引用,构造ExpandingPanels之前把ActivePanel的集合构造好,传递给ExpandingPanels,ExpandingPanels只实现点击的事件传递,然后有你写的ActivePanel来实现要如何处理事件,这样可能会好些