北京免费做网站/免费线上培训平台

ViewDragHelperde 侧滑的实现

自定义View继承自RelativeLayout

布局使用ListView 和 RecyclerView（如果继承FrameLayout会显示不全，必须继承RelativeLayout）

布局中包含两个View 用include 导入

<com.baima.swipedelete.SwipeDelete xmlns:android="http://schemas.android.com/apk/res/android"android:id="@+id/swipeDelete"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="horizontal"><include layout="@layout/layout_content"/><include layout="@layout/layout_delete"/></com.baima.swipedelete.SwipeDelete>

SwipeDelete类

public class SwipeDelete extends RelativeLayout {private ViewDragHelper dragHelper;
private View content;
private View delete;
private int deleteWidth;public SwipeDelete(Context context) {this(context, null);
}public SwipeDelete(Context context, AttributeSet attrs) {this(context, attrs, 0);
}public SwipeDelete(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);dragHelper = ViewDragHelper.create(this, callback);
}@Override
protected void onFinishInflate() {super.onFinishInflate();content = getChildAt(0);delete = getChildAt(1);
}@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {super.onSizeChanged(w, h, oldw, oldh);//获取宽和高deleteWidth = delete.getMeasuredWidth();
}@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {content.layout(0, 0, content.getMeasuredWidth(), content.getMeasuredHeight());delete.layout(content.getMeasuredWidth(), 0, content.getMeasuredWidth() + delete.getMeasuredWidth(), delete.getMeasuredHeight());}//ViewDragHelper拦截事件
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {boolean result = dragHelper.shouldInterceptTouchEvent(ev);return result;
}private float downX, downY;
private long downTime;//自己消费事件
@Override
public boolean onTouchEvent(MotionEvent event) {switch (event.getAction()) {case MotionEvent.ACTION_DOWN:downX = event.getX();downY = event.getY();downTime = System.currentTimeMillis();if (mlistener != null) {mlistener.onTouchDown(SwipeDelete.this);}break;case MotionEvent.ACTION_MOVE:float moveX = event.getX();float moveY = event.getY();//1.获取移动的dx和dyfloat dx = moveX - downX;float dy = moveY - downY;//2.判断谁大就是偏向于谁的方向if (Math.abs(dx) > Math.abs(dy)) {//说明偏向于水平，我们就认为是想滑动条目，则请求listview不要拦截requestDisallowInterceptTouchEvent(true);}break;case MotionEvent.ACTION_UP://1.按下抬起的时间long duration = System.currentTimeMillis() - downTime;//2.计算按下抬起的距离float deltaX = event.getX() - downX;float deltaY = event.getY() - downY;float distance = (float) Math.sqrt(Math.pow(deltaX, 2) + Math.pow(deltaY, 2));//如果按下抬起的时间小于500，并且按下抬起的距离小于8像素,认为是满足了执行点击的条件if (duration< ViewConfiguration.getLongPressTimeout()&&distance<ViewConfiguration.getTouchSlop()){//作用就是执行OnClickListener的onClick方法performClick();}break;}dragHelper.processTouchEvent(event);return true;
}private ViewDragHelper.Callback callback = new ViewDragHelper.Callback() {@Overridepublic boolean tryCaptureView(View child, int pointerId) {return true;}@Overridepublic int getViewHorizontalDragRange(View child) {return 1;}@Overridepublic int clampViewPositionHorizontal(View child, int left, int dx) {Log.e("222", "left=" + left);if (child == content) {left = getLeft(left);} else if (child == delete) {if (left < content.getMeasuredWidth() - delete.getMeasuredWidth()) {left = content.getMeasuredWidth() - delete.getMeasuredWidth();} else if (left > content.getMeasuredWidth()) {left = content.getMeasuredWidth();}}return left;}@Overridepublic void onViewPositionChanged(View changedView, int left, int top, int dx, int dy) {super.onViewPositionChanged(changedView, left, top, dx, dy);if (changedView == content) {//让delete伴随移动int newLeft = delete.getLeft() + dx;Log.e("tag", "getleft" + delete.getLeft() + "dx===" + dx);delete.layout(newLeft, 0, newLeft + delete.getMeasuredWidth(), delete.getBottom());} else if (changedView == delete) {//让content伴随移动int newLeft = content.getLeft() + dx;content.layout(newLeft, 0, newLeft + content.getMeasuredWidth(), content.getBottom());}if (content.getLeft() == 0) {//关闭了contentif (mlistener != null) {mlistener.close(SwipeDelete.this);}} else if (content.getLeft() == -delete.getMeasuredWidth()) {//打开了contentif (mlistener != null) {mlistener.open(SwipeDelete.this);}}}//手指抬起的释放@Overridepublic void onViewReleased(View releasedChild, float xvel, float yvel) {super.onViewReleased(releasedChild, xvel, yvel);if (content.getLeft() > -deleteWidth / 2) {//关闭onClose();} else {onOpen();}}};public void onOpen() {dragHelper.smoothSlideViewTo(content, -deleteWidth, 0);ViewCompat.postInvalidateOnAnimation(this);
}public void onClose() {dragHelper.smoothSlideViewTo(content, 0, 0);ViewCompat.postInvalidateOnAnimation(this);
}@Override
public void computeScroll() {if (dragHelper.continueSettling(true)) {ViewCompat.postInvalidateOnAnimation(this);}}private int getLeft(int left) {if (left > 0) {left = 0;} else if (left < -delete.getMeasuredWidth()) {left = -delete.getMeasuredWidth();}return left;
}private OnSwipeDeleteListener mlistener;public void setOnSwipeDeleteListener(OnSwipeDeleteListener listener) {this.mlistener = listener;
}public interface OnSwipeDeleteListener {void open(SwipeDelete swipe);void close(SwipeDelete swipe);void onTouchDown(SwipeDelete swipe);}

Adapter实现这个类回调