Android开发中模仿qq列表信息滑动删除功能

public class SlideListView extends ListView{
  private SlideItem mTouchView=null;//记录当前点击的item View
  private float mDownX;//x轴坐标
  private float mDownY;//y轴坐标
  private int mTouchState;//记录点击状态
  private int mTouchPosition;//记录点击位置
  private static final int TOUCH_STATE_NONE=0; //按下状态
  private static final int TOUCH_STATE_X=1;//横滑状态
  private static final int TOUCH_STATE_Y=2;//竖滑状态
  //判断横竖滑动的最小值
  private static final int MAX_Y=5;
  private static final int MAX_X=3;
  public SlideListView(Context context) {
    super(context);
  }
  public SlideListView(Context context, AttributeSet attrs) {
    super(context, attrs);
  }
  public SlideListView(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
  }
  @Override
  public boolean onTouchEvent(MotionEvent ev) {
    if (ev.getAction() != MotionEvent.ACTION_DOWN && mTouchView == null)
      return super.onTouchEvent(ev);
    switch (ev.getAction()) {
      case MotionEvent.ACTION_DOWN:
        //按住的item的position
        int oldPosition = mTouchPosition;
        //记录位置
        mDownX = ev.getX();
        mDownY = ev.getY();
        mTouchState = TOUCH_STATE_NONE;
        //根据当前横纵坐标点获取点击的item的position
        mTouchPosition = this.pointToPosition((int) ev.getX(), (int) ev.getY());
        //判断当前点击的是否和上次点击的item是同一个，如果是同一个，并且状态是打开了的就记录状态和坐标
        //记录坐标通过Item中的downX属性
        if (mTouchPosition == oldPosition && mTouchView != null && mTouchView.isOpen()) {
          mTouchState = TOUCH_STATE_X;
          mTouchView.onSwipe(ev);
          return true;
        }
        //获取当前的item的View
        View currentView = getChildAt(mTouchPosition - getFirstVisiblePosition());
        //如果不是同一个item 那么点击的话就关闭掉之前打开的item
        if (mTouchView != null && mTouchView.isOpen()) {
          mTouchView.smoothCloseMenu();
          mTouchView = null;
          return super.onTouchEvent(ev);
        }
        //判断该view的类型
        if (currentView instanceof SlideItem) {
          mTouchView = (SlideItem) currentView;
        }
        if (mTouchView != null) {
          mTouchView.onSwipe(ev);
        }
        break;
      case MotionEvent.ACTION_MOVE:
        float dy = Math.abs((ev.getY() - mDownY));
        float dx = Math.abs((ev.getX() - mDownX));
        if (mTouchState == TOUCH_STATE_X) {
          if (mTouchView != null) {
            //执行滑动
            mTouchView.onSwipe(ev);
          }
          return true;
        } else if (mTouchState == TOUCH_STATE_NONE) {
          //判断滑动方向，x方向执行滑动，Y方向执行滚动
          if (Math.abs(dy) > MAX_Y) {
            mTouchState = TOUCH_STATE_Y;
          } else if (dx > MAX_X) {
            mTouchState = TOUCH_STATE_X;
          }
        }
        break;
      case MotionEvent.ACTION_UP:
        //判断状态
        if (mTouchState == TOUCH_STATE_X) {
          if (mTouchView != null) {
            mTouchView.onSwipe(ev);
            //如过最后状态是打开 那么就重新初始化
            if (!mTouchView.isOpen()) {
              mTouchPosition = -1;
              mTouchView = null;
            }
          }
          ev.setAction(MotionEvent.ACTION_CANCEL);
          super.onTouchEvent(ev);
          return true;
        }
        break;
    }
    return super.onTouchEvent(ev);
  }
}

 /**
   * Called by a parent to request that a child update its values for mScrollX
   * and mScrollY if necessary. This will typically be done if the child is
   * animating a scroll using a {@link android.widget.Scroller Scroller}
   * object.
   */
  public void computeScroll() {
  }
public class SlideItem extends LinearLayout {
  private View contentView = null; //不滑动显示的view
  private View menuView = null; //左滑显示的view
  //计算滑动 动画效果
  private Scroller mOpenScroller;
  private Scroller mCloseScroller;
  private int downX; //开始按下的位置
  //记录状态
  private int state = STATE_CLOSE;
  private static final int STATE_CLOSE = 0;
  private static final int STATE_OPEN = 1;
  private int mBaseX;//在关闭滑动的时候计算与父布局的剩余距离
  public SlideItem(Context context) {
    super(context);
  }
  public SlideItem(Context context, AttributeSet attrs) {
    super(context, attrs);
  }
  public SlideItem(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
  }
  public void setContentView(View contentView, View rightView){
    this.contentView = contentView;
    this.menuView = rightView;
    //初始化mColoseScroller和mOpenScroller
    mCloseScroller=new Scroller(getContext());
    mOpenScroller = new Scroller(getContext());
    initView();
  }
  //child view的布局参数设定好后 添加到parent view里面
  private void initView() {
    //这是设置宽和高
    LayoutParams contentParams = new LayoutParams
        (LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
    LayoutParams rightParams=new LayoutParams
        (LayoutParams.WRAP_CONTENT, LayoutParams.MATCH_PARENT);
    contentView.setLayoutParams(contentParams);
    contentView.setPadding(10,10,10,10);
    menuView.setLayoutParams(rightParams);
    this.addView(contentView);
    this.addView(menuView);
  }
  // 判断是否滑出的状态
  public boolean isOpen() {
    return state == STATE_OPEN;
  }
  /**
   * 供listView调用 进行视图的移动  listView判断状态 什么情况下左滑
   * @param event
   * @return
   */
  public boolean onSwipe(MotionEvent event) {
    switch (event.getAction()) {
      case MotionEvent.ACTION_DOWN:
        downX = (int) event.getX();
        break;
      case MotionEvent.ACTION_MOVE:
        //按下位置减去移动位置 获取移动的距离
        int dis = (int) (downX - event.getX());
        if (state == STATE_OPEN) {
          dis += menuView.getWidth();
        }
        //移动
        move(dis);
        break;
      case MotionEvent.ACTION_UP:
        //当滑到右边视图一半的距离 自动滑进滑出
        if ((downX - event.getX()) > (menuView.getWidth() / 2)) {
          smoothOpenMenu();
        } else {
          smoothCloseMenu();
          return false;
        }
        break;
    }
    //消费掉事件
    return true;
  }
  /**
   * 视图重新绘制时调用
   */
  @Override
  public void computeScroll() {
    if (state == STATE_OPEN) {
      //computeScrollOffset滑动是否结束
      if (mOpenScroller.computeScrollOffset()) {
        move(mOpenScroller.getCurrX());
        postInvalidate();
      }
    } else {
      if (mCloseScroller.computeScrollOffset()) {
        move(mBaseX - mCloseScroller.getCurrX());
        postInvalidate();
      }
    }
  }
  /**
   * 移动视图
   * @param dis
   */
  private void move(int dis) {
    //这两个判断是为了保证 不要把视图移动过多 导致视图偏移
    if (dis > menuView.getWidth()) {
      dis = menuView.getWidth();
    }
    if (dis < 0) {
      dis = 0;
    }
    //view.layout()控制view相对于其父布局的位置  在触发移动的时候调用不断改变位置 完成实际的滑动效果
    contentView.layout(-dis, contentView.getTop(), contentView.getWidth() - dis, getMeasuredHeight());
    menuView.layout(contentView.getWidth() - dis, menuView.getTop(), contentView.getWidth() + menuView.getWidth() - dis, menuView.getBottom());
  }
  /**
   * 滑动关闭
   * contentView.getLeft() 与其父视图的相对位置
   */
  public void smoothCloseMenu() {
    state = STATE_CLOSE;
    mBaseX = -contentView.getLeft();
    mCloseScroller.startScroll(0, 0, mBaseX, 0, 350);
    postInvalidate();
  }
  /**
   * 滑动打开
   */
  public void smoothOpenMenu() {
    state = STATE_OPEN;
    mOpenScroller.startScroll(-contentView.getLeft(), 0, menuView.getWidth(), 0, 350);
    postInvalidate();
  }
  @Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    if(menuView != null)
      menuView.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
          MeasureSpec.makeMeasureSpec(getMeasuredHeight(), MeasureSpec.EXACTLY));
  }
  @Override
  protected void onLayout(boolean changed, int l, int t, int r, int b) {
    //确保centerView menuView的显示位置
    if(contentView != null)
      contentView.layout(0, 0, getMeasuredWidth(), contentView.getMeasuredHeight());
    if(menuView != null)
      menuView.layout(getMeasuredWidth(), 0, getMeasuredWidth() + menuView.getMeasuredWidth(), contentView.getMeasuredHeight());
  }
}

public class SlideAdapter extends BaseAdapter implements View.OnClickListener{
  private List<String> dataList;
  private Context context;
  private LayoutInflater inflater;
  public SlideAdapter(Context context, List<String> dataList) {
    this.context = context;
    this.dataList = dataList;
    this.inflater=LayoutInflater.from(context);
  }
  @Override
  public int getCount() {
    return 5;
  }
  @Override
  public Object getItem(int position) {
    return null;
  }
  @Override
  public long getItemId(int position) {
    return 0;
  }
  @Override
  public View getView(int position, View convertView, ViewGroup parent) {
    ViewHolder holder=null;
    if (convertView==null){
      View content=inflater.inflate(R.layout.adapter_item_content,null);
      View menu=inflater.inflate(R.layout.adapter_item_menu,null);
      holder=new ViewHolder(content,menu);
      SlideItem slideItem=new SlideItem(context);
      slideItem.setContentView(content,menu);
      convertView=slideItem;
      convertView.setTag(holder);
    }else {
      holder= (ViewHolder) convertView.getTag();
    }
    holder.itemTvDelete.setOnClickListener(this);
    holder.itemTvNoRead.setOnClickListener(this);
    holder.itemTvToTop.setOnClickListener(this);
    return convertView;
  }
  class ViewHolder{
    TextView itemTvToTop;
    TextView itemTvNoRead;
    TextView itemTvDelete;
    public ViewHolder(View center,View menu) {
      this.itemTvToTop = (TextView) menu.findViewById(R.id.item_to_top);
      this.itemTvNoRead = (TextView) menu.findViewById(R.id.item_no_read);
      this.itemTvDelete = (TextView) menu.findViewById(R.id.item_delete);
    }
  }
  @Override
  public void onClick(View v) {
    switch (v.getId()){
      case R.id.item_no_read:
        Toast.makeText(context,"标为未读",Toast.LENGTH_SHORT).show();
        break;
      case R.id.item_to_top:
        Toast.makeText(context,"置顶了熬",Toast.LENGTH_SHORT).show();
        break;
      case R.id.item_delete:
        Toast.makeText(context,"删除啦",Toast.LENGTH_SHORT).show();
        break;
    }
  }
}