给滚动条加监听事件，急。。。。

[reandyner]

public void adjustmentValueChanged(AdjustmentEvent e) {
System.out.println(e.getAdjustmentType());
}
1、拖动滑动条 结果打印是 5
2、点击三角箭头 结果打印是 5
3、点击滚动条空白处 结果打印是 5

api上AdjustmentType有五种类型

点击滚动条空白处上 BLOCK_DECREMENT 3
点击滚动条空白处下 BLOCK_INCREMENT 4
拖动滑动条 TRACK 5
点击三角箭头向上 UNIT_DECREMENT 2
点击三角箭头向下 UNIT_INCREMENT 1

为什么现在1、2、3的操作都打印 5 代表是拖动滑动条

[reandyner]

如下面的代码
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Event;
import java.awt.Rectangle;
import java.awt.event.AdjustmentEvent;
import java.awt.event.AdjustmentListener;
import java.awt.event.MouseWheelEvent;
import java.awt.event.MouseWheelListener;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollBar;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JViewport;
import javax.swing.UIManager;
import javax.swing.border.EmptyBorder;

/**
* @author Azure
* @version 1.0 31/03/07
*/
public class AzWindowsScrollFrame extends JFrame implements AdjustmentListener {
JScrollBar vScrollBar = new JScrollBar();

JScrollBar hScrollBar = new JScrollBar();

JTable table;
int i=0;

public AzWindowsScrollFrame() {
init();
}

public static void main(String[] args) {
try {
UIManager
.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
} catch (Exception e) {
System.err.println("Something went wrong!");
}
AzWindowsScrollFrame sf = new AzWindowsScrollFrame();
sf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
sf.setLocationRelativeTo(null);
sf.setSize(new Dimension(300, 200));
sf.setVisible(true);
}

private void init() {
this.setLayout(new BorderLayout());

Object data[][] = { { "one", "1", "swing" }, { "two", "2", "is" },
{ "three", "3", "very" }, { "four", "4", "nice" },
{ "five", "5", "swing" }, { "six", "6", "is" },
{ "seven", "7", "very" }, { "eight", "8", "nice" },
{ "nine", "9", "swing" }, { "ten", "10", "is" } };
Object headers[] = { "col1", "col2", "col3" };
table = new JTable(data, headers);
table.setPreferredSize(new Dimension(500, 300));

JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
JScrollPane scrollPane = new JScrollPane(table);
scrollPane
.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_NEVER);
scrollPane
.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
scrollPane.setBorder(new EmptyBorder(0, 0, 0, 0));
panel.setBorder(new EmptyBorder(0, 0, 0, 0));
panel.add(scrollPane, BorderLayout.CENTER);

JPanel hPanel = new JPanel(new BorderLayout());

hScrollBar.setOrientation(JScrollBar.HORIZONTAL);
int visibleAmount = 100;
hScrollBar.setVisibleAmount(visibleAmount);
hPanel.add(hScrollBar, BorderLayout.CENTER);

JLabel vConerlabel = new JLabel();
vConerlabel.setMinimumSize(new Dimension(15, 10));
vConerlabel.setPreferredSize(new Dimension(15, 10));
vConerlabel.setBorder(new EmptyBorder(0, 0, 0, 0));
hPanel.add(vConerlabel, BorderLayout.EAST);

vScrollBar.addAdjustmentListener(this);
int hVisibleAmount = 60;
vScrollBar.setVisibleAmount(hVisibleAmount);
vScrollBar.setUnitIncrement(60);
vScrollBar.setValueIsAdjusting(true);

vScrollBar.addMouseWheelListener(new MouseWheelListener() {
public void mouseWheelMoved(MouseWheelEvent e) {
vScrollBar.setValue(vScrollBar.getValue()
+ e.getWheelRotation() * 60);
}
});
hScrollBar.addAdjustmentListener(this);
hScrollBar.addMouseWheelListener(new MouseWheelListener() {
public void mouseWheelMoved(MouseWheelEvent e) {
hScrollBar.setValue(hScrollBar.getValue()
+ e.getWheelRotation() * 60);
}
});

this.add(hPanel, BorderLayout.SOUTH);
this.add(panel, BorderLayout.CENTER);
this.add(vScrollBar, BorderLayout.EAST);
}

public void adjustmentValueChanged(AdjustmentEvent e) {
if (e.getSource() == vScrollBar) {
System.out.println(e.getAdjustmentType());

} else if (e.getSource() == hScrollBar) {
scrollToTableH(table, e.getValue());
}
}

public void scrollToTableH(JTable table, int value) {
if (!(table.getParent() instanceof JViewport)) {
return;
}
JViewport viewport = (JViewport) table.getParent();
Rectangle viewRect = viewport.getViewRect();
Rectangle rect = new Rectangle(value * table.getWidth() / 90,
(int) viewRect.getY(), 10, 10);

rect.setLocation(rect.x - viewRect.x, rect.y - viewRect.y);
viewport.scrollRectToVisible(rect);
}

public void scrollToTableV(JTable table, int value) {
if (!(table.getParent() instanceof JViewport)) {
return;
}
JViewport viewport = (JViewport) table.getParent();
Rectangle viewRect = viewport.getViewRect();
Rectangle rect = new Rectangle((int) viewRect.getX(), value
* table.getHeight() / 90, 10, 10);

rect.setLocation(rect.x - viewRect.x, rect.y - viewRect.y);
viewport.scrollRectToVisible(rect);
}

}

[afunx]

刚试了一下，4的操作也打印5.可能无论你怎么操作，都变相等于在拖动了。不明原因。顶一个！期待高手。

[sunyiz]

在JScrollBar的源代码中找到以下几段源代码

private ChangeListener fwdAdjustmentEvents = new ModelListener();//实例化了一个ModelListener的对象fwdAdjustmentEvents 
public JScrollBar(int orientation, int value, int extent, int min, int max) {//构造函数
    ...
    this.model.addChangeListener(fwdAdjustmentEvents);给JScrollBar添加ChangeListener——fwdAdjustmentEvents 
    ...
}

那ModelListener是怎么定义的呢？
看下面

    private class ModelListener implements ChangeListener, Serializable {
        public void stateChanged(ChangeEvent e)   {
	    Object obj = e.getSource();
	    if (obj instanceof BoundedRangeModel) {
		int id = AdjustmentEvent.ADJUSTMENT_VALUE_CHANGED;//id赋值AdjustmentEvent.ADJUSTMENT_VALUE_CHANGED
		int type = AdjustmentEvent.TRACK;//type赋值AdjustmentEvent.TRACK
		BoundedRangeModel model = (BoundedRangeModel)obj;
		int value = model.getValue();
		boolean isAdjusting = model.getValueIsAdjusting();
		fireAdjustmentValueChanged(id, type, value, isAdjusting);//以id、type为参数调用fireAdjustmentValueChanged方法
	    }
        }
    }

那fireAdjustmentValueChanged方法是怎么定义的呢？
看下面

    private void fireAdjustmentValueChanged(int id, int type, int value,
					    boolean isAdjusting) {
        Object[] listeners = listenerList.getListenerList();//把listenerList中的对象全取出来放在listeners数组中
        AdjustmentEvent e = null;
        for (int i = listeners.length - 2; i >= 0; i -= 2) {
            if (listeners[i]==AdjustmentListener.class) {
                if (e == null) {
                    e = new AdjustmentEvent(this, id, type, value, isAdjusting);
                }
                ((AdjustmentListener)listeners[i+1]).adjustmentValueChanged(e);//对listeners数组中的对象依次产生adjustmentValueChanged事件
            }          
        }
    }   

其实整个JScrollBar中的代码，
对listenerList产生事件的唯一一个方法就是fireAdjustmentValueChanged
（而你addAdjustmentListener实际上也是往listenerList中添加的）
看到这里有没有发现什么问题了？
adjustmentValueChanged的事件实际上是在fireAdjustmentValueChanged方法中产生的
而fireAdjustmentValueChanged方法是ModelListener中的stateChanged方法中调用的
而JScrollBar在构造的时候，就已经添加了一个ModelListener
而ModelListener中的stateChanged方法仅仅会产生type为TRACK（5）的事件
这就是为什么无论你怎么在JScrollBar上点击，都只会产生type为TRACK（5）的事件的原因了

[reandyner]

你好sunyiz
我现在就是想捕捉到不同操作的不同Type，不知道通过什么方法可以解决呢，期待。。。。

[sunyiz]

你先说下你要捕捉这些事件的用意，
我看下有没有什么简单的实现方法
最通用的（当然也是最复杂的）方法是自己重写JScrollBar
我也不希望这样，所以先看下你的需求

我写了个捕捉上下箭头的例子给你看下，这个比较简单

import java.awt.Container;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollBar;
import javax.swing.JScrollPane;
import javax.swing.plaf.basic.BasicScrollBarUI;

public class MyScrollBar extends JScrollBar{
	public MyScrollBar() {
		super();
		setUI(new MyScrollBarUI());
	}
	
	public MyScrollBar(int orientation) {
		super(orientation, 0, 10, 0, 100);
		setUI(new MyScrollBarUI());
    }
	
	class MyScrollBarUI extends BasicScrollBarUI {

		protected void installComponents(){
			super.installComponents();
			incrButton.addActionListener(new ActionListener(){
				public void actionPerformed(ActionEvent e) {
					System.out.println("incrButton");
				}
			});
			decrButton.addActionListener(new ActionListener(){
				public void actionPerformed(ActionEvent e) {
					System.out.println("decrButton");
				}
			});
		}
	}
	
	public static void main(String[] args) {
		JFrame frame = new JFrame();
		frame.setSize(200, 200);
		frame.setLocationRelativeTo(null);//居中
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		Container content = frame.getContentPane();
		JPanel pnl = new JPanel();
		pnl.setPreferredSize(new Dimension(200,500));
		JScrollPane scrPane = new JScrollPane(pnl);
		scrPane.setVerticalScrollBar(new MyScrollBar());
		content.add(scrPane);
		frame.setVisible(true);
	}
}

[reandyner]

是为了实时监控，问题得到解决，谢谢