我现在做的程序要求有"鹰眼"功能:在屏幕上首先有一个"大的绘图区域",在该区域内你可以绘制图形;再次你定义一个"小的区域"大的绘图区域的一个缩影,当你在一个"小的区域内"拖动一个方块的时候,"大的绘图区域"内的图形跟着同步移动.我这里有个例子,可以直接运行,例子可以到[email protected],密码是123456下载运行,谁能告诉我是怎么做的?本人非常谢谢!!!!!!!!
调试欢乐多
test.jpg 文件找个大点儿的能看到效果
------------------------------------------------------------import java.awt.*;
import java.awt.event.MouseEvent;import javax.swing.*;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
import javax.swing.event.MouseInputListener;public class NavigateTest
{ public static void main(String[] args)
{
JLabel label = new JLabel(new ImageIcon("C:/test.jpg")); JScrollPane sp = new JScrollPane(label);
NavigateView nv = new NavigateView(sp, label, 0.2);
JPanel p = new JPanel();
p.add(nv);
nv.setBorder(BorderFactory.createLineBorder(Color.black)); JFrame f = new JFrame("NavigateTest");
f.getContentPane().add(sp, BorderLayout.CENTER);
f.setSize(500, 400);
f.setLocation(200, 200);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true); JFrame nf = new JFrame("NavigateView");
nf.getContentPane().add(p, BorderLayout.CENTER);
nf.pack();
nf.setLocation(f.getX() + f.getWidth(), f.getY());
nf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
nf.setVisible(true);
} private static class NavigateView extends JComponent
implements ChangeListener, MouseInputListener
{
private JComponent targetComponent = null;
private double scale;
private Point anchorPoint;
private JViewport viewport;
private Point viewportAnchorPos; private Image bufferImage = null;
private boolean needRepaintBuffer = false; public NavigateView(JScrollPane scrollPane, JComponent component, double scale)
{
targetComponent = component;
this.viewport = scrollPane.getViewport();
this.scale = scale; this.viewport.addChangeListener(this);
this.addMouseListener(this);
this.addMouseMotionListener(this);
setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
} public Dimension getPreferredSize()
{
Dimension d = targetComponent.getPreferredSize();
d.width *= scale;
d.height *= scale; Insets insets = getInsets();
d.width += insets.left + insets.right;
d.height += insets.top + insets.bottom; return d;
}
protected void paintComponent(Graphics g)
{
if (bufferImage == null || needRepaintBuffer) {
prepareBufferedImage();
} Insets insets = getInsets();
g.translate(insets.left, insets.top); Rectangle rect = targetComponent.getVisibleRect();
rect.x *= scale;
rect.y *= scale;
rect.width *= scale;
rect.height *= scale; g.drawImage(bufferImage, 0, 0, getWidth(), getHeight(), null, this);
g.setColor(Color.red);
g.drawRect(rect.x, rect.y, rect.width-1, rect.height-1); g.translate(-insets.left, -insets.top);
}
public void repaintBuffer()
{
needRepaintBuffer = true;
} private void prepareBufferedImage()
{
if (bufferImage == null ||
bufferImage.getWidth(this) < getWidth() ||
bufferImage.getHeight(this) < getHeight()) {
bufferImage = this.createImage(getWidth(), getHeight());
}
Graphics2D g2d = (Graphics2D) bufferImage.getGraphics();
g2d.scale(scale, scale);
targetComponent.paint(g2d);
g2d.dispose(); needRepaintBuffer = false;
} public void stateChanged(ChangeEvent e)
{
repaint();
} public void mousePressed(MouseEvent e)
{
Point p = e.getPoint();
Rectangle rect = targetComponent.getVisibleRect(); if (rect.contains(p.x / scale, p.y / scale)) {
this.anchorPoint = p;
this.viewportAnchorPos = viewport.getViewPosition();
}
else {
int x = (int) (p.x / scale - rect.width / 2);
int y = (int) (p.y / scale - rect.height / 2);
setViewPositon(x, y); this.viewportAnchorPos = viewport.getViewPosition();
rect = viewport.getViewRect();
this.anchorPoint = new Point(
(int)((rect.x + rect.width / 2) * scale),
(int)((rect.y + rect.height/ 2) * scale));
}
} public void mouseDragged(MouseEvent e)
{
Point p = e.getPoint();
int dx = (int) ((p.x - anchorPoint.x) / scale);
int dy = (int) ((p.y - anchorPoint.y) / scale); Point viewportPos = viewport.getViewPosition();
viewportPos.x = viewportAnchorPos.x + dx;
viewportPos.y = viewportAnchorPos.y + dy; setViewPositon(viewportPos.x, viewportPos.y);
} private void setViewPositon(int x, int y)
{
Rectangle rect = viewport.getViewRect(); x = Math.max(x, 0);
y = Math.max(y, 0);
x = Math.min(x, targetComponent.getWidth() - rect.width);
y = Math.min(y, targetComponent.getHeight() - rect.height); viewport.setViewPosition(new Point(x, y));
} public void mouseClicked(MouseEvent e) {}
public void mouseReleased(MouseEvent e) {}
public void mouseEntered(MouseEvent e) {}
public void mouseExited(MouseEvent e) {}
public void mouseMoved(MouseEvent e) {}
}
}
这个图形实际就是Model,大的显示区域,和小的显示区域是分别的两个View,这两个View都对这个Model进行监听,一旦Model被触发,同时对2个View产生影响。如果楼主对MVC模式和java swing都比较熟悉的话,不难实现。