Android-related content

One:

Foreground process:

The foreground process has the highest priority,

Visible Processes:

The Android system typically has a small number of visible processes.

Service process:

No user interface,

Background process:

There are generally more background processes.

Empty process:

Processes that do not include any active components, priority cleanup.

Two:

Four components:

Activity, service, Broadcastreceiver,contextprovider

Four states of activity: active, paused, stopped, inactive. The activity stack adheres to the last-in-first-out rule. callback function: Oncreate,onstart,onrestart,onresume,onpause,onstop, OnDestroy. Life Cycle Reference: http://blog.csdn.net/liuhe688/article/details/6733407

　　

The difference between OnPause and onsaveinstancestate:

OnPause () is typically used to hold persistent data and to store data in a file system or database system on a storage device.

Onsaveinstancestate () is mainly used to save dynamic state information, the information is generally stored in the bundle bundle is able to save a variety of format data objects in the Onsaveinstancestate () stored in the bundle data, System Onrestoreinstancestate () and OnCreate () are also used by the bundle to pass the data to the function

The Onsaveinstancestate call is to save the state of the current activity.

Logcat Commissioning

Three: User interface basics

Framework for Android user interface: The Android UI framework uses the MVC model.

User interface framework with view tree

Interface controls are divided into specified controls and system controls

Testview,edittext,button,imagebutton

　　　　　　

　　

Android-related content