Android之淘宝商品列表长按遮罩效果的实现

/***
 * 长按条目遮罩界面
 */
public class ItemMaskLayout extends LinearLayout {

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

  public ItemMaskLayout(Context context, @Nullable AttributeSet attrs) {
    this(context, attrs, 0);
  }

  public ItemMaskLayout(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
    LayoutInflater.from(context).inflate(R.layout.layout_product_list_item_mask, this, true);
    findViewById(R.id.tv_find_same).setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        if (mItemMaskClickListener != null) {
          mItemMaskClickListener.findTheSame();
        }
      }
    });
    findViewById(R.id.tv_collection).setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        if (mItemMaskClickListener != null) {
          mItemMaskClickListener.collection();
        }
      }
    });
  }

  public ItemMaskClickListener mItemMaskClickListener;
  public void setMaskItemClickListener(ItemMaskClickListener listener) {
    this.mItemMaskClickListener = listener;
  }

  //提供遮罩中按钮点击操作接口 自定义
  public interface ItemMaskClickListener {
    void findTheSame();
    void collection();
  }
}

/**
 * 长按条目添加遮罩操作帮助类
 */
public class ItemLongClickMaskHelper {
  private FrameLayout mRootFrameLayout;
  private ItemMaskLayout mMaskItemLayout;
  private Context mContext;
  private ScaleAnimation anim;
  private String productId;
  public ItemLongClickMaskHelper(Context context){
    this.mCOntext= context;
    mMaskItemLayout = new ItemMaskLayout(mContext);
    anim = new ScaleAnimation(
        0f, 1.0f, 1.0f, 1.0f,
        Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f
    );
    anim.setDuration(300);
    mMaskItemLayout.setOnClickListener(new View.OnClickListener() {
      @Override
      public void onClick(View v) {
        dismissItemMaskLayout();
      }
    });

    mMaskItemLayout.setOnLongClickListener(new View.OnLongClickListener() {
      @Override
      public boolean onLongClick(View v) {
        dismissItemMaskLayout();
        return true;
      }
    });

    mMaskItemLayout.setMaskItemClickListener(new ItemMaskLayout.ItemMaskClickListener() {
      @Override
      public void findTheSame() {
        ToastUtil.showCustomToast("找相似 " + productId);
      }

      @Override
      public void collection() {
        ToastUtil.showCustomToast("收藏 " + productId);
      }
    });
  }

  public ItemLongClickMaskHelper setRootFrameLayout(FrameLayout frameLayout, String fundId){
    if (mRootFrameLayout != null){
      mRootFrameLayout.removeView(mMaskItemLayout);
    }
    mRootFrameLayout = frameLayout;
    this.productId = fundId;
    mRootFrameLayout.addView(mMaskItemLayout);
    mMaskItemLayout.startAnimation(anim);
    return this;
  }

  public ItemLongClickMaskHelper setMaskItemListener(ItemMaskLayout.ItemMaskClickListener listener){
    this.mMaskItemLayout.setMaskItemClickListener(listener);
    return this;
  }

  /**
   * 遮罩消失
   */
  public void dismissItemMaskLayout(){
    if (mRootFrameLayout != null){
      mRootFrameLayout.removeView(mMaskItemLayout);
    }
  }
}

public class TouchCallbackRecyclerView extends RecyclerView {
   public TouchCallbackRecyclerView(Context context) {
    super(context);
  }

  public TouchCallbackRecyclerView(Context context, @Nullable AttributeSet attrs) {
    super(context, attrs);
  }

  public TouchCallbackRecyclerView(Context context, @Nullable AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
  }

  public interface ScrollCallback {
    /**
     * 滑动手指抬起事件
     *
     * @param diffY 抬起时相对于按下时的偏移量
大于0：列表往下拉, 小于0： 列表往上拉
     */
    void onTouchUp(float diffY);
  }

  private ScrollCallback mScrollCallback;
  public void setScrollCallback(ScrollCallback callback) {
    this.mScrollCallback = callback;
  }

  private float mDownY, mMovingY, mUpY;
  private boolean isUp = false;

  @SuppressWarnings("deprecation")
  private static final float SLOP = ViewConfiguration.getTouchSlop();

  @Override
  public boolean dispatchTouchEvent(MotionEvent ev) {
    switch (ev.getAction()) {
      case MotionEvent.ACTION_DOWN:
        mDownY = ev.getY();
        isUp = false;
        break;
      case MotionEvent.ACTION_MOVE:
        mMovingY = ev.getY();
        isUp = false;
        break;
      case MotionEvent.ACTION_UP:
        mUpY = ev.getY();
        isUp = true;
        break;
    }
    if (isUp && mScrollCallback != null && Math.abs(mUpY - mDownY) > SLOP) {
      mScrollCallback.onTouchUp(mMovingY - mDownY);
    }
    return super.dispatchTouchEvent(ev);
  }
}