The borderless design intent of the Android application framework

The description of the external feature space of the Android application framework is clearly described in the SDK documentation, with a detailed description of the basic concepts of Android applications, the lifecycle of components, and so on. In the outside feature space, Android provides concepts such as Activity,service,broadcast receivers,content Provider,intent,task, which I don't discuss here, Because the SDK documentation is detailed enough.

While reading the SDK documentation and studying the concept of activity, I felt the design intent of Android free-from-borders, which was looming in Android. Android application is just a virtual concept, and there is no actual entrance, this is not like the concept of the application on the window platform, Android is more to provide the concept of components. Why do you want to blur the concept of an application? I think this emptiness is the direct embodiment of free and borderless design intent. Highlighting requests and services, highlighting the individual components, weakening the boundaries, the various components of the system can be free of borderless communication, the service requester directly requests, regardless of where and to whom, the components are free independent individuals, an application can directly request the use of other components of the application, This is the core concept of Android application framework design, and everything else is in the service of this core concept.

Let the programmer ignore the concept of the application, or even completely discard the concept of the process, the programmer sees a component, the application programmer to use these components to form a so-called application, then the designer first of all to consider? I think it should be an abstract application model that produces concepts and interfaces under this model.

We know that Microsoft has put forward the concept of application,windows, the concept of a promising application (Foreground application), and the user interaction in Microsoft's application model is entirely given to the window, The rendering of various interfaces belongs to this application, which is isolated, the constituent objects of the application can not access each other, at most provide an inter-process communication mechanism, which is also the application level. While Microsoft has later proposed concepts such as components, distributed components, but these are not rooted in Windows systems, Android is a complete component-building idea, and the first application concept is Activity,service,broadcast Receivers,content Provider,intent,task. These concepts embody the nature of a human-computer Interaction model:

• Interface rendering
• Initiating a request, responding to a request
• Content interaction
• Message Receive processing

Activity is the core concept of Android applications, in short, the activity for the user interaction manager, there is a visual interface to render, and service and activity is the difference between him running in the background, no interface rendering. The meaning of intent is the intention that he represents the message in the conceptual space of Android, which represents the intent of the request.

Activity can exist everywhere, provide services, eliminate spatial differences, activity is an independent individual, more able to show the essence of object-oriented. The individual is required to receive information from another individual and can initiate a request to another individual at any time. The individual is free, Android you can start an activity, but there is no right to eliminate an activity, which is the embodiment of individual rights, the elimination of the individual is determined by the system, this is the human meaning of the activity contained in Android.