android.graphics.RectF#setEmpty ( )源码实例Demo

/**
 * Calculates the chip icon's ChipDrawable-absolute bounds (top-left is <code>
 * [ChipDrawable.getBounds().left, ChipDrawable.getBounds().top]</code>).
 */
private void calculateChipIconBounds(@NonNull Rect bounds, @NonNull RectF outBounds) {
  outBounds.setEmpty();

  if (showsChipIcon() || showsCheckedIcon()) {
    float offsetFromStart = chipStartPadding + iconStartPadding;
    float chipWidth = getCurrentChipIconWidth();

    if (DrawableCompat.getLayoutDirection(this) == ViewCompat.LAYOUT_DIRECTION_LTR) {
      outBounds.left = bounds.left + offsetFromStart;
      outBounds.right = outBounds.left + chipWidth;
    } else {
      outBounds.right = bounds.right - offsetFromStart;
      outBounds.left = outBounds.right - chipWidth;
    }

    float chipHeight = getCurrentChipIconHeight();
    outBounds.top = bounds.exactCenterY() - chipHeight / 2f;
    outBounds.bottom = outBounds.top + chipHeight;
  }
}
 

/**
 * Calculates the chip text's ChipDrawable-absolute bounds (top-left is <code>
 * [ChipDrawable.getBounds().left, ChipDrawable.getBounds().top]</code>).
 */
private void calculateTextBounds(@NonNull Rect bounds, @NonNull RectF outBounds) {
  outBounds.setEmpty();

  if (text != null) {
    float offsetFromStart = chipStartPadding + calculateChipIconWidth() + textStartPadding;
    float offsetFromEnd = chipEndPadding + calculateCloseIconWidth() + textEndPadding;

    if (DrawableCompat.getLayoutDirection(this) == ViewCompat.LAYOUT_DIRECTION_LTR) {
      outBounds.left = bounds.left + offsetFromStart;
      outBounds.right = bounds.right - offsetFromEnd;
    } else {
      outBounds.left = bounds.left + offsetFromEnd;
      outBounds.right = bounds.right - offsetFromStart;
    }

    // Top and bottom included for completion. Don't position the chip text vertically based on
    // these bounds. Instead, use #calculateTextOriginAndAlignment().
    outBounds.top = bounds.top;
    outBounds.bottom = bounds.bottom;
  }
}
 

/**
 * Calculates the close icon's ChipDrawable-absolute bounds (top-left is <code>
 * [ChipDrawable.getBounds().left, ChipDrawable.getBounds().top]</code>).
 */
private void calculateCloseIconBounds(@NonNull Rect bounds, @NonNull RectF outBounds) {
  outBounds.setEmpty();

  if (showsCloseIcon()) {
    float offsetFromEnd = chipEndPadding + closeIconEndPadding;

    if (DrawableCompat.getLayoutDirection(this) == ViewCompat.LAYOUT_DIRECTION_LTR) {
      outBounds.right = bounds.right - offsetFromEnd;
      outBounds.left = outBounds.right - closeIconSize;
    } else {
      outBounds.left = bounds.left + offsetFromEnd;
      outBounds.right = outBounds.left + closeIconSize;
    }

    outBounds.top = bounds.exactCenterY() - closeIconSize / 2f;
    outBounds.bottom = outBounds.top + closeIconSize;
  }
}
 

private void calculateCloseIconTouchBounds(@NonNull Rect bounds, @NonNull RectF outBounds) {
  outBounds.setEmpty();

  if (showsCloseIcon()) {
    float offsetFromEnd =
        chipEndPadding
            + closeIconEndPadding
            + closeIconSize
            + closeIconStartPadding
            + textEndPadding;

    if (DrawableCompat.getLayoutDirection(this) == ViewCompat.LAYOUT_DIRECTION_LTR) {
      outBounds.right = bounds.right;
      outBounds.left = outBounds.right - offsetFromEnd;
    } else {
      outBounds.left = bounds.left;
      outBounds.right = bounds.left + offsetFromEnd;
    }

    outBounds.top = bounds.top;
    outBounds.bottom = bounds.bottom;
  }
}
 

@Override
public void getTouchBound(ScrollbarRecyclerView view, RectF bound, int slop) {
    if (mAnimatorValue == 0 && !mAlwaysTouchable) {
        bound.setEmpty();
        return;
    }
    if (mTouchStartOnBar) {
        bound.set(mSliderBound.left - slop,
                view.getPaddingTop() + mPaddingStart - slop,
                mSliderBound.right + slop,
                view.getHeight() - view.getPaddingBottom() - mPaddingEnd
                        + slop);
    } else {
        bound.set(mSliderBound.left - slop,
                mSliderBound.top - slop,
                mSliderBound.right + slop,
                mSliderBound.bottom + slop);
    }
}
 

@Override
public void getTouchBound(ScrollbarRecyclerView view, RectF bound, int slop) {
    if (mAnimatorValue == 0 && !mAlwaysTouchable) {
        bound.setEmpty();
        return;
    }
    if (mTouchStartOnBar) {
        bound.set(view.getPaddingLeft() + mPaddingStart - slop,
                mSliderBound.top - slop,
                view.getWidth() - view.getPaddingRight() - mPaddingEnd + slop,
                mSliderBound.bottom + slop);
    } else {
        bound.set(mSliderBound.left - slop,
                mSliderBound.top - slop,
                mSliderBound.right + slop,
                mSliderBound.bottom + slop);
    }
}
 

private void updateDrawableBounds(DrawableInfo drawableInfo) {
    final Drawable drawable = drawableInfo.mDrawable;

    final float radius = mSteinerCircleRadius;
    if (radius <= 0) {
        drawable.setBounds(0, 0, 0, 0);
        return;
    }


    final int dWidth = drawable.getIntrinsicWidth();
    final int dHeight = drawable.getIntrinsicHeight();

    final RectF bounds = mTempBounds;
    bounds.setEmpty();

    if (dWidth <= 0 || dHeight <= 0 || dWidth == dHeight || FitType.FIT == mFitType) {
        bounds.inset(-radius, -radius);
    } else {
        float scale;
        if (dWidth > dHeight) {
            scale = radius / (float) dHeight;
        } else {
            scale = radius / (float) dWidth;
        }
        bounds.inset(-dWidth * scale, -dHeight * scale);

        if (FitType.START == mFitType || FitType.END == mFitType) {
            int dir = FitType.START == mFitType ? 1 : -1;
            bounds.offset((bounds.width() * 0.5f - radius) * dir,
                    (bounds.height() * 0.5f - radius) * dir);
        }
    }

    bounds.offset(drawableInfo.mCenterX, drawableInfo.mCenterY);
    drawable.setBounds((int) bounds.left, (int) bounds.top,
            Math.round(bounds.right), Math.round(bounds.bottom));
}
 

/**
 * 获取绘制区域
 */
void getDrawRect(RectF rectF) {
    if (!imageZoomer.isWorking()) {
        if (SLog.isLoggable(SLog.LEVEL_VERBOSE | SLog.TYPE_ZOOM)) {
            SLog.v(NAME, "not working. getDrawRect");
        }
        rectF.setEmpty();
        return;
    }

    Size drawableSize = imageZoomer.getDrawableSize();
    rectF.set(0, 0, drawableSize.getWidth(), drawableSize.getHeight());

    getDrawMatrix().mapRect(rectF);
}
 

/**
 * Merges a {@link RectF} into an existing list of any objects which contain a rectangle.
 * While merging, this method makes sure that:
 *
 * <ol>
 * <li>No rectangle is redundant (contained within a bigger rectangle)</li>
 * <li>Rectangles of the same height and vertical position that intersect get merged</li>
 * </ol>
 *
 * @param list      the list of rectangles (or other rectangle containers) to merge the new
 *                  rectangle into
 * @param candidate the {@link RectF} to merge into the list
 * @param extractor a function that can extract a {@link RectF} from an element of the given
 *                  list
 * @param packer    a function that can wrap the resulting {@link RectF} into an element that
 *                  the list contains
 * @hide
 */
@VisibleForTesting
public static <T> void mergeRectangleIntoList(final List<T> list,
        final RectF candidate, final Function<T, RectF> extractor,
        final Function<RectF, T> packer) {
    if (candidate.isEmpty()) {
        return;
    }

    final int elementCount = list.size();
    for (int index = 0; index < elementCount; ++index) {
        final RectF existingRectangle = extractor.apply(list.get(index));
        if (existingRectangle.contains(candidate)) {
            return;
        }
        if (candidate.contains(existingRectangle)) {
            existingRectangle.setEmpty();
            continue;
        }

        final boolean rectanglesContinueEachOther = candidate.left == existingRectangle.right
                || candidate.right == existingRectangle.left;
        final boolean canMerge = candidate.top == existingRectangle.top
                && candidate.bottom == existingRectangle.bottom
                && (RectF.intersects(candidate, existingRectangle)
                || rectanglesContinueEachOther);

        if (canMerge) {
            candidate.union(existingRectangle);
            existingRectangle.setEmpty();
        }
    }

    for (int index = elementCount - 1; index >= 0; --index) {
        final RectF rectangle = extractor.apply(list.get(index));
        if (rectangle.isEmpty()) {
            list.remove(index);
        }
    }

    list.add(packer.apply(candidate));
}
 

@Override
protected RectF resetInstance(RectF obj) {
    obj.setEmpty();
    return obj;
}
 

@Override
protected RectF resetInstance(RectF obj) {
  obj.setEmpty();
  return obj;
}
 

@Override
protected RectF resetInstance(RectF obj) {
    obj.setEmpty();
    return obj;
}
 

@Override
protected RectF resetInstance(RectF obj) {
    obj.setEmpty();
    return obj;
}
 

@Override
protected RectF resetInstance(RectF obj) {
    obj.setEmpty();
    return obj;
}
 

@Override
protected RectF resetInstance(RectF obj) {
    obj.setEmpty();
    return obj;
}
 

@Override
protected RectF resetInstance(RectF obj) {
    obj.setEmpty();
    return obj;
}
 

@Override
protected RectF resetInstance(RectF obj) {
    obj.setEmpty();
    return obj;
}
 

void onDraw(@NonNull Canvas canvas) {
    final RectF drawRectF = tempDisplayRectF;
    imageZoomer.getDrawRect(drawRectF);
    if (drawRectF.isEmpty()) {
        if (SLog.isLoggable(SLog.LEVEL_DEBUG | SLog.TYPE_ZOOM)) {
            SLog.d(ImageZoomer.NAME, "displayRectF is empty. drawScrollBar. drawRectF=%s", drawRectF.toString());
        }
        return;
    }

    Size viewSize = imageZoomer.getViewSize();
    final int viewWidth = viewSize.getWidth();
    final int viewHeight = viewSize.getHeight();
    final float displayWidth = drawRectF.width();
    final float displayHeight = drawRectF.height();

    if (viewWidth <= 0 || viewHeight <= 0 || displayWidth == 0 || displayHeight == 0) {
        if (SLog.isLoggable(SLog.LEVEL_DEBUG | SLog.TYPE_ZOOM)) {
            SLog.d(ImageZoomer.NAME, "size is 0. drawScrollBar. viewSize=%dx%d, displaySize=%sx%s",
                    viewWidth, viewHeight, displayWidth, displayHeight);
        }
        return;
    }

    ImageView imageView = imageZoomer.getImageView();
    final int finalViewWidth = viewWidth - (scrollBarMargin * 2);
    final int finalViewHeight = viewHeight - (scrollBarMargin * 2);

    if ((int) displayWidth > viewWidth) {
        final float widthScale = (float) viewWidth / displayWidth;
        final int horScrollBarWidth = (int) (finalViewWidth * widthScale);

        RectF horScrollBarRectF = scrollBarRectF;
        horScrollBarRectF.setEmpty();
        horScrollBarRectF.left = imageView.getPaddingLeft() + scrollBarMargin + (drawRectF.left < 0 ? (int) ((Math.abs(drawRectF.left) / drawRectF.width()) * finalViewWidth) : 0);
        horScrollBarRectF.top = imageView.getPaddingTop() + scrollBarMargin + finalViewHeight - scrollBarSize;
        horScrollBarRectF.right = horScrollBarRectF.left + horScrollBarWidth;
        horScrollBarRectF.bottom = horScrollBarRectF.top + scrollBarSize;
        canvas.drawRoundRect(horScrollBarRectF, scrollBarRadius, scrollBarRadius, scrollBarPaint);
    }

    if ((int) displayHeight > viewHeight) {
        final float heightScale = (float) viewHeight / displayHeight;
        final int verScrollBarHeight = (int) (finalViewHeight * heightScale);

        RectF verScrollBarRectF = scrollBarRectF;
        verScrollBarRectF.setEmpty();
        verScrollBarRectF.left = imageView.getPaddingLeft() + scrollBarMargin + finalViewWidth - scrollBarSize;
        verScrollBarRectF.top = imageView.getPaddingTop() + scrollBarMargin + (drawRectF.top < 0 ? (int) ((Math.abs(drawRectF.top) / drawRectF.height()) * finalViewHeight) : 0);
        verScrollBarRectF.right = verScrollBarRectF.left + scrollBarSize;
        verScrollBarRectF.bottom = verScrollBarRectF.top + verScrollBarHeight;
        canvas.drawRoundRect(verScrollBarRectF, scrollBarRadius, scrollBarRadius, scrollBarPaint);
    }
}