Android app UI design

1. Menu Design

Press the device menu key to display the Options menu, which contains two groups of menu items: Icon menu (up to 6 menu items are supported, and checkboxes or radio buttons are not supported) and extended menu expanded menu;

Context menu is a floating menu list, which usually appears when you press the view;

Sub-menu submenu is also a floating menu list, which is displayed by selecting menu items in the option menu or context menu. nested sub-menus are not supported.

2. viewgroup controls the display position of the View through various layout methods.

3. layout types: absolutelayout, relativelayout, framelayout, gridview, linearlayout, listlayout, radiogroup, tablelayout ......

4. Color: Android. Graphics. Color

5. typeface Font Style: Android. Graphics. typeface; font (bold, bold_italic, italic, normal) × style (default, default_bold, monospace, sans_serif, Serif)

6. Set a listener for the view to process user input: view. onclicklistener, view. onlongclicklistener, view. onfocuschangelistener, view. onkeylistener, view. ontouchlistener, view. oncreatemenulistener

7. process priority sequence: foreground process → visible process → started service process → background process) → Empty Process)

8. Activity Status: active, paused, stop, and finish

Shows the lifecycle of an activity.

Shows activity status management.

9. Service: A service is a program that runs in the background without a user interface. It can run in its own process or in the Context context of other applications; other components can be bound to a service and called through Remote Procedure Call (RPC. [For example, a media player that plays a song from the playlist]

10. intent: intent describes what the application wants to do. The two most important parts of the intent data structure are actions (typical types include main, view, pick, and edit) android uses intent to move between the screen and the screen.

11. intentfilter: intentfilter describes the intent that an activity or intentreceiver can operate on. It must be defined in androidmanifest. xml. This mechanism provides two key advantages: the activity can reuse a request generated in intent form from other components; it can be replaced by a new activity with the same intentfilter at any time.

12. intentreceiver: Register in androidmanifest. xml. You can also use context. registerreceiver () in the Code for registration. Balabala

13. content provider: This solution shares data between different application packages. All preference settings, files, and databases created by Android applications are private, an application can create a content provider to share data of other applications. Android local content providers include calllog, contact. People. Phones, and setting. system.

12. aidl: Android Interface Definition Language