Remoteviews layout and type restriction source code analysis

One 、 Official documents

Two 、 The definition of a class

3、 ... and 、RemoteView annotation

        stay RemoteViews The following comments are declared in the source code ：

        From the perspective of annotation type, it is runtime annotation , Acting on a class or interface , Combined with the annotation, we can see that this annotation is used for View Subclasses of , Used to identify the View Whether it can be used as a remote view . It can be inferred from this that , Not all View Can be used as a remote view , It's just a statement RemoteView Annotated View Can only be .

        Give several definitions in the source code ：

Four 、Filter Interface

        It is not difficult to see from the notes ,Filter Class is used to restrict and filter View Of . Not all of the above View Can be used as a remote view , If it is listed above View, be onLoadClass(Class clazz) return true, Otherwise return to false.

        stay RemoteViews in ,Filter Implementation of interface methods ：

        if onLoadClass(Class clazz) return false, The following exception is thrown .