Coloring.java 文件源码

/**
 * Tries to clone and simply color-filter the drawable. Uses {@link PorterDuff.Mode#SRC_ATOP}.
 * <b>Note</b>: Use this when you don't know which drawable you have.
 *
 * @param drawable Which drawable to color
 * @param color    Which color to use
 * @return A colored drawable ready for use
 */
@NonNull
public static Drawable colorUnknownDrawable(@NonNull final Drawable drawable, @ColorInt final int color) {
    // check if this is a drawable wrapper, then do coloring by drawable wrapping
    if (drawable instanceof DrawableWrapper || drawable instanceof android.support.v7.graphics.drawable.DrawableWrapper) {
        final Drawable wrapResult = colorDrawableWrapped(drawable, color);
        if (Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN_MR2) {
            // there is a bug for JellyBean MR2 when this won't work, so.. set the tint filter manually
            wrapResult.setColorFilter(new PorterDuffColorFilter(color, PorterDuff.Mode.SRC_ATOP));
        }
        return wrapResult;
    }

    // wrapping failed, do a plain constant state clone
    try {
        final Drawable.ConstantState state = drawable.getConstantState();
        if (state == null) {
            // well done android.
            throw new IllegalStateException("Constant state is unavailable");
        }
        final Drawable copy = drawable.getConstantState().newDrawable().mutate();
        copy.setColorFilter(color, PorterDuff.Mode.SRC_ATOP);
        return copy;
    } catch (Exception ignored) {
        return drawable;
    }
}