android实现简单左滑删除控件

本文为大家分享了一个简单的android左滑删除控件，供大家参考，具体内容如下

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(0,0,child.getMeasuredWidth(),child.getMeasuredHeight());
//  }else {
 child.layout(left,0,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),widthMeasureSpec,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();
}
}

}

使用

<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>

效果

来源：https://blog.csdn.net/qq_20352713/article/details/85063628