bit地图&bit地图drawable的有关问题

bitmap&bitmapdrawable的问题

    /**     * Create drawable from a bitmap, setting initial target density based on     * the display metrics of the resources.     */    public BitmapDrawable(Resources res, Bitmap bitmap) {        this(new BitmapState(bitmap), res);        mBitmapState.mTargetDensity = mTargetDensity;    }