判断用于Glide的Context是否有效

isValidContext.java

    /**
     * 判断用于Glide的Context是否有效
     *
     * @param context 用于Glide的Context
     * @return 用于Glide的Context是否有效
     */
    public static boolean isValidContext(final Context context) {
        if (context == null) {
            return false;
        }
        if (context instanceof Activity) {
            final Activity activity = (Activity) context;
            return !activity.isDestroyed() && !activity.isFinishing();
        }
        return true;
    }