コード例 #1
0
  @Override
  public void onDrag(float dx, float dy) {
    if (mScaleDragDetector.isScaling()) {
      return; // Do not drag if we are already scaling
    }

    if (DEBUG) {
      LogManager.getLogger().d(LOG_TAG, String.format("onDrag: dx: %.2f. dy: %.2f", dx, dy));
    }

    ImageView imageView = getImageView();
    mSuppMatrix.postTranslate(dx, dy);
    checkAndDisplayMatrix();

    /**
     * Here we decide whether to let the ImageView's parent to start taking over the touch event.
     *
     * <p>First we check whether this function is enabled. We never want the parent to take over if
     * we're scaling. We then check the edge we're on, and the direction of the scroll (i.e. if
     * we're pulling against the edge, aka 'overscrolling', let the parent take over).
     */
    ViewParent parent = imageView.getParent();
    if (mAllowParentInterceptOnEdge && !mScaleDragDetector.isScaling() && !mBlockParentIntercept) {
      if (mScrollEdge == EDGE_BOTH
          || (mScrollEdge == EDGE_LEFT && dx >= 1f)
          || (mScrollEdge == EDGE_RIGHT && dx <= -1f)) {
        if (null != parent) parent.requestDisallowInterceptTouchEvent(false);
      }
    } else {
      if (null != parent) {
        parent.requestDisallowInterceptTouchEvent(true);
      }
    }
  }
コード例 #2
0
  @SuppressLint("ClickableViewAccessibility")
  @Override
  public boolean onTouch(View v, MotionEvent ev) {
    boolean handled = false;

    if (mZoomEnabled && hasDrawable((ImageView) v)) {
      ViewParent parent = v.getParent();
      switch (ev.getAction()) {
        case ACTION_DOWN:
          // First, disable the Parent from intercepting the touch
          // event
          if (null != parent) {
            parent.requestDisallowInterceptTouchEvent(true);
          } else {
            LogManager.getLogger().i(LOG_TAG, "onTouch getParent() returned null");
          }

          // If we're flinging, and the user presses down, cancel
          // fling
          cancelFling();
          break;

        case ACTION_CANCEL:
        case ACTION_UP:
          // If the user has zoomed less than min scale, zoom back
          // to min scale
          if (getScale() < mMinScale) {
            RectF rect = getDisplayRect();
            if (null != rect) {
              v.post(
                  new AnimatedZoomRunnable(getScale(), mMinScale, rect.centerX(), rect.centerY()));
              handled = true;
            }
          }
          break;
      }

      // Try the Scale/Drag detector
      if (null != mScaleDragDetector) {
        boolean wasScaling = mScaleDragDetector.isScaling();
        boolean wasDragging = mScaleDragDetector.isDragging();

        handled = mScaleDragDetector.onTouchEvent(ev);

        boolean didntScale = !wasScaling && !mScaleDragDetector.isScaling();
        boolean didntDrag = !wasDragging && !mScaleDragDetector.isDragging();

        mBlockParentIntercept = didntScale && didntDrag;
      }

      // Check to see if the user double tapped
      if (null != mGestureDetector && mGestureDetector.onTouchEvent(ev)) {
        handled = true;
      }
    }

    return handled;
  }