<强> Android TouchListener实现拖拽删实例代码
如果为一个控件设置了该触摸监听,控件会随着用户的拖动而移动,如果拖动的距离大过设置的临界值,那么当松开手指时会有回调onDragComplete,用户可在该方法中将该控件从父布局中删除,或这进行其他操作。如果用户拖拽的距离小于临界值,那么当用户松开手指时控件会回谈到原来的初始位置。这时会触发onDragRebound回调。如果用户触摸控件之后没有拖拽而是直接松开手指,会触发onClick回调,这样用户就不用为该控件设置onClick监听。
源码如下:
进口android.util.Log;
进口android.view.MotionEvent;
进口android.view.View;
进口android.view.ViewGroup;/* *
*由zhangjg 14-10-10。
*/公共类DragTouchListener实现视图。OnTouchListener {/* *
*拖动方向
*/公共静态最终int DIRECTION_UP=0;
公共静态最终int DIRECTION_DOWN=1;
公共静态最终int DIRECTION_LEFT=2;
公共静态最终int DIRECTION_RIGHT=3;
私人int mDragDirection=1;
私人int mDragDistance=1;
私人ViewGroup。MarginLayoutParams mParams;
私人ViewGroup。MarginLayoutParams mOriginParams;
私人int viewOriginMargin=-1000;
私人浮动mStartY=0;
私人浮动mStartX=0;
私人布尔isTouched=false;
公共DragTouchListener (int dragDirection int dragDistance) {
mDragDirection=dragDirection;
mDragDistance=dragDistance;
}
保护无效onClick(查看视图){
}
保护无效onDragComplete(查看视图){
}
保护无效onDragRebound(查看视图){
}
@Override
公共布尔ondraw(查看视图,MotionEvent MotionEvent) {
如果(viewOriginMargin==-1000) {
mParams=(ViewGroup.MarginLayoutParams) view.getLayoutParams ();
如果(mDragDirection==DIRECTION_UP) {
viewOriginMargin=mParams.bottomMargin;
}else if (mDragDirection==DIRECTION_DOWN) {
viewOriginMargin=mParams.topMargin;
}else if (mDragDirection==DIRECTION_LEFT) {
viewOriginMargin=mParams.rightMargin;
}else if (mDragDirection==DIRECTION_RIGHT) {
viewOriginMargin=mParams.leftMargin;
}
}
int action=motionEvent.getAction ();
开关(行动){
案例MotionEvent.ACTION_DOWN:
isTouched=true;
mStartY=motionEvent.getY ();
mStartX=motionEvent.getX ();
返回true;
案例MotionEvent.ACTION_MOVE:
浮动y=motionEvent.getY ();
浮动x=motionEvent.getX ();
如果(mDragDirection==DIRECTION_UP) {
如果(y & lt;mStartY) {
mParams。页下空白=viewOriginMargin + (int) (mStartY - y);
}
}else if (mDragDirection==DIRECTION_DOWN) {
如果(y比;mStartY) {
mParams。页面顶栏=viewOriginMargin + (int) (y - mStartY);
}
}else if (mDragDirection==DIRECTION_LEFT) {
如果(x & lt;mStartX) {
mParams。rightMargin=viewOriginMargin + (int) (mStartX - x);
}
}else if (mDragDirection==DIRECTION_RIGHT) {
如果x比;mStartX) {
mParams。leftMargin=viewOriginMargin + (int) (x - mStartX);
}
}
view.setLayoutParams (mParams);
打破;
案例MotionEvent.ACTION_UP:
浮动nowY=motionEvent.getY ();
浮动nowX=motionEvent.getX ();
int△=(int) nowX - (int) mStartX;
intδy=(int) nowY - (int) mStartY;
如果(isTouched,,Math.abs (△) & lt;5,,Math.abs(δy) & lt;5){
onClick(查看);
打破;
}
如果(mDragDirection==DIRECTION_UP) {
如果(isTouched,,mStartY - nowY比;mDragDistance) {//日志。我(“test-drag”、“方向,startY=" + mStartY +”, nowY=" + nowY +//?startY - nowY=" + (mStartY - nowY) +“, dragDistance:”+ mDragDistance);
onDragComplete(查看);
}else if (mStartY - nowY祝辞0,,mStartY - nowY & lt;mDragDistance) {
mParams。页下空白=viewOriginMargin;
view.setLayoutParams (mParams);
onDragRebound(查看);
}
}else if (mDragDirection==DIRECTION_DOWN) {
如果(isTouched,,nowY - mStartY比;mDragDistance) {
onDragComplete(查看);
}else if (nowY - mStartY祝辞0,,nowY - mStartY & lt;mDragDistance) {
mParams。页面顶栏=viewOriginMargin;
view.setLayoutParams (mParams);
onDragRebound(查看);
}
}else if (mDragDirection==DIRECTION_LEFT) {
如果(isTouched,,mStartX - nowX比;mDragDistance) {
onDragComplete(查看);
}else if (mStartX - nowX祝辞0,,mStartX - nowX & lt;mDragDistance) {
mParams。rightMargin=viewOriginMargin;
view.setLayoutParams (mParams);
onDragRebound(查看);
}
}else if (mDragDirection==DIRECTION_RIGHT) {
如果(isTouched,,nowX - mStartX比;mDragDistance) {
onDragComplete(查看);
}else if (nowX - mStartX祝辞0,,nowX - mStartX & lt;mDragDistance) {
mParams。leftMargin=viewOriginMargin;
view.setLayoutParams (mParams);
onDragRebound(查看);
}
}
isTouched=false;
打破;
}
返回错误;
}
}
