从源码解析，为何AppWidget不支持自定义View

为何AppWidget不支持自定义View？

几个大类RemoveViews, RemoveViewsService, RemoveViewsFactory就不说了。不是本节主题。

 

切入正题，直接从AppWidgetHostView.java开始讲。这就相当于Activity的DecorView。

贴一段代码先，来自AppWidgetHostView.java版本：5.1

    /**

     * Inflate and return the default layout requested by AppWidget provider.

     */

    protected View getDefaultView() {

        ......

 

        try {

            if (mInfo != null) {

                Context theirContext = getRemoteContext();

                mRemoteContext= theirContext;

                LayoutInflater inflater = (LayoutInflater)

                        theirContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

                inflater = inflater.cloneInContext(theirContext);

                inflater.setFilter(sInflaterFilter);

                AppWidgetManager manager = AppWidgetManager.getInstance(mContext);

                Bundle options = manager.getAppWidgetOptions(mAppWidgetId);

 

                int layoutId = mInfo.initialLayout;

                ......

                defaultView = inflater.inflate(layoutId, this, false);

            } else {

                Log.w(TAG, "can't inflate defaultView because mInfo is missing");

            }

        } catch (RuntimeException e) {

            exception = e;

        }

 

        ......

 

        return defaultView;

}

再看下面这段代码sInflaterFilter的定义

    // When we're inflating the initialLayout for a AppWidget, we only allow

    // views that are allowed in RemoteViews.

    static final LayoutInflater.Filter sInflaterFilter = new LayoutInflater.Filter() {

        public boolean onLoadClass(Class clazz) {

            return clazz.isAnnotationPresent(RemoteViews.RemoteView.class);

        }

    };

再贴一段getRemoteContext()的实现