FloatingActionButtonLollipop.java 文件源码

@Override
void setBackgroundDrawable(ColorStateList backgroundTint,
        PorterDuff.Mode backgroundTintMode, int rippleColor, int borderWidth) {
    // Now we need to tint the shape background with the tint
    mShapeDrawable = DrawableCompat.wrap(createShapeDrawable());
    DrawableCompat.setTintList(mShapeDrawable, backgroundTint);
    if (backgroundTintMode != null) {
        DrawableCompat.setTintMode(mShapeDrawable, backgroundTintMode);
    }

    final Drawable rippleContent;
    if (borderWidth > 0) {
        mBorderDrawable = createBorderDrawable(borderWidth, backgroundTint);
        rippleContent = new LayerDrawable(new Drawable[]{mBorderDrawable, mShapeDrawable});
    } else {
        mBorderDrawable = null;
        rippleContent = mShapeDrawable;
    }

    mRippleDrawable = new RippleDrawable(ColorStateList.valueOf(rippleColor),
            rippleContent, null);

    mContentBackground = mRippleDrawable;

    mShadowViewDelegate.setBackgroundDrawable(mRippleDrawable);
}