Android implements simple left slide delete control

This article shares a simple Android left slide delete control for your reference. The specific contents are as follows

import android.animation.ValueAnimator;
import android.content.Context;
import android.graphics.PointF;
import android.support.v4.view.ViewConfigurationCompat;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;

public class SwipeLayout extends ViewGroup{
 public static String TAG = "SwipeLayout";

 //可以滚动的距离
 int mSwipeWidth;

 PointF firstPoint;
 PointF lastPoint;

 float mTouchSlop;

 ValueAnimator openAnimator;
 ValueAnimator closeAnimator;

 public SwipeLayout(Context context) {
  this(context,null);
 }

 public SwipeLayout(Context context,AttributeSet attrs) {
  super(context,attrs);
  mTouchSlop = ViewConfigurationCompat.getScaledPagingTouchSlop(ViewConfiguration.get(getContext()));
 }

 @Override
 protected void onLayout(boolean changed,int l,int t,int r,int b) {
  int left=0;
  int childCount = getChildCount();

  for (int i=0;i<childCount;++i){
   View child = getChildAt(i);

   //按顺序从左往右排
//   if (i==0){
//    child.layout(0,child.getMeasuredWidth(),child.getMeasuredHeight());
//   }else {
    child.layout(left,left+child.getMeasuredWidth(),child.getMeasuredHeight());
//   }
   left += child.getMeasuredWidth();
  }

 }

 @Override
 protected void onMeasure(int widthMeasureSpec,int heightMeasureSpec) {
  super.onMeasure(widthMeasureSpec,heightMeasureSpec);
  int childCount = getChildCount();
  View mainChild = getChildAt(0);
  int width=0;
  int height=0;
  mSwipeWidth = 0;
//  measureChild(mainChild,widthMeasureSpec,heightMeasureSpec);
  measure(widthMeasureSpec,heightMeasureSpec);

  //滑动距离是 从index开始 所有控件的宽度之和
  if (childCount>1) {
   for (int i = 1; i < childCount; ++i) {
    mSwipeWidth += getChildAt(i).getMeasuredWidth();
   }
  }

  int widthMode = MeasureSpec.getMode(widthMeasureSpec);
  int widthValue = MeasureSpec.getSize(widthMeasureSpec);
  int heightMode = MeasureSpec.getMode(heightMeasureSpec);
  int heightValue = MeasureSpec.getSize(heightMeasureSpec);

  switch (heightMode){
   case MeasureSpec.AT_MOST:
   case MeasureSpec.UNSPECIFIED:
    //没有指定大小 按照第一个子控件的大小来设置
    height = mainChild.getMeasuredHeight();
    break;
   case MeasureSpec.EXACTLY:
    height = heightValue;
    break;
  }
  switch (widthMode){
   case MeasureSpec.AT_MOST:
   case MeasureSpec.UNSPECIFIED:
    //没有指定大小 按照第一个子控件的大小来设置
    width = mainChild.getMeasuredWidth();
    break;
   case MeasureSpec.EXACTLY:
    width = widthValue;
    break;
  }

//  for (int i=1;i<childCount;++i){
//   measureChild(getChildAt(i),MeasureSpec.makeMeasureSpec(height,MeasureSpec.EXACTLY));
//  }
  setMeasuredDimension(width,height);
 }

 @Override
 public boolean dispatchTouchEvent(MotionEvent ev) {
  return super.dispatchTouchEvent(ev);
 }

 @Override
 public boolean onInterceptTouchEvent(MotionEvent ev) {
    switch (ev.getAction()){
   case MotionEvent.ACTION_DOWN:
    firstPoint = new PointF(ev.getX(),ev.getY());
    lastPoint = new PointF(ev.getX(),ev.getY());
    break;
   case MotionEvent.ACTION_MOVE:
    float moveDistance = ev.getX()-firstPoint.x;

    //移动距离大于制定值 认为进入控件的滑动模式
    if (Math.abs(moveDistance) > mTouchSlop ){
     //让父控件不拦截我们的事件
     getParent().requestDisallowInterceptTouchEvent(true);
     //拦截事件
     return true;
    }

  }
  return super.onInterceptTouchEvent(ev);
 }

 @Override
 public boolean onTouchEvent(MotionEvent ev) {
  switch (ev.getAction()){
   case MotionEvent.ACTION_MOVE:
    float moveDistance = ev.getX()-lastPoint.x;
    lastPoint = new PointF(ev.getX(),ev.getY());

    // 这里要注意 x大于0的时候 往左滑动 小于0往右滑动
    scrollBy((int) -moveDistance,0);

    //边界判定 超过了边界 直接设置为边界值
    if (getScrollX()> mSwipeWidth){
     scrollTo(mSwipeWidth,0);
    }else if (getScrollX()<0){
     scrollTo(0,0);
    }
    break;
   case MotionEvent.ACTION_UP:
    //没动 不理他
    if (getScrollX()== mSwipeWidth ||getScrollX()==0){
     return false;
    }
     float distance = ev.getX()-firstPoint.x;
    //滑动距离超过 可滑动距离指定值 继续完成滑动
     if (Math.abs(distance) > mSwipeWidth *0.3 ){
      if (distance>0){
       smoothClose();
      }else if (distance<0){
       smoothopen();
      }
     }else {
      if (distance>0){
       smoothopen();

      }else if (distance<0){
       smoothClose();
      }
     }
     return true;
  }

  return super.onTouchEvent(ev);
 }

 public void smoothopen(){

  clearAnimator();
  openAnimator = ValueAnimator.ofInt(getScrollX(),mSwipeWidth);
  openAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
   @Override
   public void onAnimationUpdate(ValueAnimator animation) {
    Integer integer = (Integer) animation.getAnimatedValue();
    scrollTo(integer,0);
   }
  });
  openAnimator.start();
 }
 public void smoothClose(){
  clearAnimator();
  closeAnimator = ValueAnimator.ofInt(getScrollX(),0);
  closeAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
   @Override
   public void onAnimationUpdate(ValueAnimator animation) {
    Integer integer = (Integer) animation.getAnimatedValue();
    scrollTo(integer,0);
   }
  });
  closeAnimator.start();

 }

 public void open(){
  scrollTo(mSwipeWidth,0);
 }
 public void close(){
  scrollTo(0,0);

 }
//执行滑动动画必须先清除动画 不然会鬼畜
 private void clearAnimator(){
  if (closeAnimator!=null && closeAnimator.isRunning()){
   closeAnimator.cancel();
   closeAnimator = null;
  }
  if (openAnimator!=null && openAnimator.isRunning()) {
   openAnimator.cancel();
   openAnimator = null;
  }
 }

 public void toggle(){
  if (getScrollX()==0){
   open();
  }else {
   close();
  }
 }

}

use

<com.example.chenweiqi.simplerefreshview.widget.SwipeLayout
  android:id="@+id/swipeLayout"
  android:layout_width="200dp"
  android:layout_height="wrap_content"
  android:background="#F3F3F3"
>
<Button
  android:id="@+id/btn"
  android:text="123"
  android:layout_width="match_parent"
  android:layout_height="50dp" />

<Button
  android:background="#FF0000"
  android:text="shanchu"
  android:layout_width="80dp"
  android:layout_height="match_parent" />
<TextView
  android:gravity="center"
  android:textAlignment="center"
  android:background="#0F0"
  android:text="123"
  android:layout_width="30dp"
  android:layout_height="match_parent" />
</com.example.chenweiqi.simplerefreshview.widget.SwipeLayout>

effect

The above is the whole content of this article. I hope it will help you in your study, and I hope you will support us a lot.