android 侧滑删除 实例源码

【实例截图】

【核心代码】

package com.exampledelete;

import android.content.Context;
import android.graphics.Rect;
import android.support.v4.app.Fragment;
import android.support.v4.widget.ViewDragHelper;
import android.support.v4.widget.ViewDragHelper.Callback;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewDebug;
import android.widget.FrameLayout;

public class SwipeLayout extends FrameLayout {

	private ViewDragHelper mDragHelper;
	private View frontView;
	private View backView;
	private int width;
	private int height;
	private int mRange;
	
	public SwipeLayout(Context context, AttributeSet attrs) {
		this(context, attrs,0);
	}

	public SwipeLayout(Context context) {
		this(context,null);
	}
	public SwipeLayout(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		mDragHelper=ViewDragHelper.create(this,1.5f,MCallBack());
	}

	  Callback MCallBack() {
		return new Callback() {
			
			@Override
			public boolean tryCaptureView(View arg0, int arg1) {
				return true;
			}
			//设置移动范围
			@Override
			public int clampViewPositionHorizontal(View child, int left, int dx) {
				if(child==frontView){
					if(left>0){
						left=0;
					}else if(left<-mRange){
						left=-mRange;
					}
				}else if(child==backView){
					if(left>width){
						left=width;
					}else if(left<width-mRange){
						left=width-mRange;
					}
				}
				return left;
			}
			@Override
			public void onViewPositionChanged(View changedView, int left,
					int top, int dx, int dy) {
				super.onViewPositionChanged(changedView, left, top, dx, dy);
				if(changedView==frontView){
					backView.offsetLeftAndRight(dx);
				}else if(changedView==backView){
					frontView.offsetLeftAndRight(dx);
				}
				// 兼容老版本
				invalidate();
			}
			
			
		};
	}

	@Override
	public boolean onInterceptTouchEvent(MotionEvent ev) {
		return mDragHelper.shouldInterceptTouchEvent(ev);
	}
    @Override
    public boolean onTouchEvent(MotionEvent event) {
    	mDragHelper.processTouchEvent(event);
    	return true;
    }
    @Override
    protected void onLayout(boolean changed, int left, int top, int right,
    		int bottom) {
    	super.onLayout(changed, left, top, right, bottom);
        LayoutView(false);
    }

	private void LayoutView(boolean isopen) {
		Rect frontRect = getFrontRect(isopen);
		frontView.layout(frontRect.left, frontRect.top, frontRect.right, frontRect.bottom);
		Rect BackRect = getbackRect(frontRect);
		backView.layout(BackRect.left, BackRect.top, BackRect.right, BackRect.bottom);
		// 调整顺序, 把mFrontView前置
		bringChildToFront(frontView);
	}
    
    private Rect getbackRect(Rect frontRect) {
    	int left = frontRect.right;
		return new Rect(left,0, left mRange, height);
	}

	private Rect getFrontRect(boolean isopen) {
    	int left = 0;
		if(isopen){
			left=-mRange;
		}
		return new Rect(left,0, left width, height);
	}

	@Override
    protected void onFinishInflate() {
    	super.onFinishInflate();
    	frontView = getChildAt(1);
    	backView = getChildAt(0);
    }
    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    	super.onSizeChanged(w, h, oldw, oldh);
    	width = frontView.getMeasuredWidth();
    	height = frontView.getMeasuredHeight();
    	mRange = backView.getMeasuredWidth();
    } 
}