我确信这是可能的,但我所有的搜索都是空白的。
在Java中,是否可以在Java应用程序之外注册鼠标运动事件?因此,如果鼠标指针移动到屏幕上的任何位置,我会收到回电。轮询MouseInfo.getPointerInfo
可以进行近似,但必须有更好的方法。
由于
解释用例: 这只是一个宠物项目,但基本上当鼠标击中屏幕边缘时触发事件。我还在想,如果你试图推过屏幕的边缘,可能会触发不同的事件。为此,我认为鼠标运动监听器可能更合适。
答案 0 :(得分:11)
java.awt.event.MouseMotionListener
只会向您提供有关应用程序窗口内鼠标移动的信息。对于在该窗口之外发生的事件,MouseInfo.getPointerInfo
无法解决。但是,您可以编写一个(可能是单例)类来定期轮询指针信息并允许添加MouseMotionListeners
:
import java.awt.Component;
import java.awt.MouseInfo;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
import java.util.HashSet;
import java.util.Set;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
/**
* This class checks the position every #DELAY milliseconds and
* informs all registered MouseMotionListeners about position updates.
*/
public class MouseObserver {
/* the resolution of the mouse motion */
private static final int DELAY = 10;
private Component component;
private Timer timer;
private Set<MouseMotionListener> mouseMotionListeners;
protected MouseObserver(Component component) {
if (component == null) {
throw new IllegalArgumentException("Null component not allowed.");
}
this.component = component;
/* poll mouse coordinates at the given rate */
timer = new Timer(DELAY, new ActionListener() {
private Point lastPoint = MouseInfo.getPointerInfo().getLocation();
/* called every DELAY milliseconds to fetch the
* current mouse coordinates */
public synchronized void actionPerformed(ActionEvent e) {
Point point = MouseInfo.getPointerInfo().getLocation();
if (!point.equals(lastPoint)) {
fireMouseMotionEvent(point);
}
lastPoint = point;
}
});
mouseMotionListeners = new HashSet<MouseMotionListener>();
}
public Component getComponent() {
return component;
}
public void start() {
timer.start();
}
public void stop() {
timer.stop();
}
public void addMouseMotionListener(MouseMotionListener listener) {
synchronized (mouseMotionListeners) {
mouseMotionListeners.add(listener);
}
}
public void removeMouseMotionListener(MouseMotionListener listener) {
synchronized (mouseMotionListeners) {
mouseMotionListeners.remove(listener);
}
}
protected void fireMouseMotionEvent(Point point) {
synchronized (mouseMotionListeners) {
for (final MouseMotionListener listener : mouseMotionListeners) {
final MouseEvent event =
new MouseEvent(component, MouseEvent.MOUSE_MOVED, System.currentTimeMillis(),
0, point.x, point.y, 0, false);
SwingUtilities.invokeLater(new Runnable() {
public void run() {
listener.mouseMoved(event);
}
});
}
}
}
/* Testing the ovserver */
public static void main(String[] args) {
JFrame main = new JFrame("dummy...");
main.setSize(100,100);
main.setVisible(true);
MouseObserver mo = new MouseObserver(main);
mo.addMouseMotionListener(new MouseMotionListener() {
public void mouseMoved(MouseEvent e) {
System.out.println("mouse moved: " + e.getPoint());
}
public void mouseDragged(MouseEvent e) {
System.out.println("mouse dragged: " + e.getPoint());
}
});
mo.start();
}
}
请注意,与标准MouseMotionListener存在一些显着差异:
mouseMoved
个活动,而不会收到mouseDragged
个活动。那是因为无法接收有关主窗口外点击的信息。modifiers
的{{1}}将始终为0. MouseEvent
,clickCount
,popupTrigger
button
,用作java.awt.Component
的(假)来源 - 此处不允许MouseEvent
值。