android中返回键事件

在android中重写父类的onkeydown方法，就可以更方便的操作了。

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
// TODO Auto-generated method stub
if(keyCode==KeyEvent.KEYCODE_BACK&&event.getRepeatCount()==0){
	//需要处理
}
	return false;
}

 长按事件

@Override
public boolean onKeyLongPress(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_CALL) {
        // a long press of the call key.
        // do our work, returning true to consume it. by
        // returning true, the framework knows an action has
        // been performed on the long press, so will set the
        // canceled flag for the following up event.
        return true;
    }
    return super.onKeyLongPress(keyCode, event);
}

 

 

@Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_CALL && event.isTracking()
            && !event.isCanceled()) {
        // if the call key is being released, AND we are tracking
        // it from an initial key down, AND it is not canceled,
        // then handle it.
        return true;
    }
    return super.onKeyUp(keyCode, event);
}

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_0) {
        // this tells the framework to start tracking for
        // a long press and eventual key up. it will only
        // do so if this is the first down (not a repeat).
        event.startTracking();
        return true;
    }
    return super.onKeyDown(keyCode, event);
}

@Override
public boolean dispatchKeyEvent(KeyEvent event) {
    if (event.getKeyCode() == KeyEvent.KEYCODE_BACK) {
        if (event.getAction() == KeyEvent.ACTION_DOWN
                && event.getRepeatCount() == 0) {

            // Tell the framework to start tracking this event.
            getKeyDispatcherState().startTracking(event, this);
            return true;

        } else if (event.getAction() == KeyEvent.ACTION_UP) {
            getKeyDispatcherState().handleUpEvent(event);
            if (event.isTracking() && !event.isCanceled()) {

                // DO BACK ACTION HERE
                return true;

            }
        }
        return super.dispatchKeyEvent(event);
    } else {
        return super.dispatchKeyEvent(event);
    }
}