Example usage for android.graphics Canvas rotate

Introduction

In this page you can find the example usage for android.graphics Canvas rotate.

Prototype

public void rotate(float degrees)

Source Link

Document

Preconcat the current matrix with the specified rotation.

Usage

From source file:com.ferdi2005.secondgram.support.widget.RecyclerView.java

@Override
public void draw(Canvas c) {
    super.draw(c);

    final int count = mItemDecorations.size();
    for (int i = 0; i < count; i++) {
        mItemDecorations.get(i).onDrawOver(c, this, mState);
    }/*w w w . j av a2  s  .  c  om*/
    // TODO If padding is not 0 and clipChildrenToPadding is false, to draw glows properly, we
    // need find children closest to edges. Not sure if it is worth the effort.
    boolean needsInvalidate = false;
    if (mLeftGlow != null && !mLeftGlow.isFinished()) {
        final int restore = c.save();
        final int padding = mClipToPadding ? getPaddingBottom() : 0;
        c.rotate(270);
        c.translate(-getHeight() + padding, 0);
        needsInvalidate = mLeftGlow != null && mLeftGlow.draw(c);
        c.restoreToCount(restore);
    }
    if (mTopGlow != null && !mTopGlow.isFinished()) {
        final int restore = c.save();
        if (mClipToPadding) {
            c.translate(getPaddingLeft(), getPaddingTop());
        }
        c.translate(0, topGlowOffset);
        needsInvalidate |= mTopGlow != null && mTopGlow.draw(c);
        c.restoreToCount(restore);
    }
    if (mRightGlow != null && !mRightGlow.isFinished()) {
        final int restore = c.save();
        final int width = getWidth();
        final int padding = mClipToPadding ? getPaddingTop() : 0;
        c.rotate(90);
        c.translate(-padding, -width);
        needsInvalidate |= mRightGlow != null && mRightGlow.draw(c);
        c.restoreToCount(restore);
    }
    if (mBottomGlow != null && !mBottomGlow.isFinished()) {
        final int restore = c.save();
        c.rotate(180);
        if (mClipToPadding) {
            c.translate(-getWidth() + getPaddingRight(), -getHeight() + getPaddingBottom());
        } else {
            c.translate(-getWidth(), -getHeight());
        }
        needsInvalidate |= mBottomGlow != null && mBottomGlow.draw(c);
        c.restoreToCount(restore);
    }

    // If some views are animating, ItemDecorators are likely to move/change with them.
    // Invalidate RecyclerView to re-draw decorators. This is still efficient because children's
    // display lists are not invalidated.
    if (!needsInvalidate && mItemAnimator != null && mItemDecorations.size() > 0 && mItemAnimator.isRunning()) {
        needsInvalidate = true;
    }

    if (needsInvalidate) {
        ViewCompat.postInvalidateOnAnimation(this);
    }
}