Monitor status changes

To ensure Activity Responds to status changes, Android Provides a series of event processors. When Activity In its Full , Visible And Active These processors are triggered during lifetime migration. Figure 3-8 Just Activity Status, which outlines these lifetime.

 

Figure3-8

 

The following frameworkCodeAActivityMethod processor for available state change events. There are some prompts in each method, describing the recommended actions in each state change event.

 

Package com. paad. myapplication;

 

Import Android. App. activity;

Import Android. OS. Bundle;

Public class myactivity extends activity {

 

// InFullLife cycle.

@ Override

Public void oncreate (bundle icicle ){

Super. oncreate (icicle );

// InitializationActivity.

}

 

// InOncreateCalled after completion to restoreUIStatus.

@ Override

Public void onrestoreinstancestate (bundle savedinstancestate ){

Super. onrestoreinstancestate (savedinstancestate );

// Restore from savedinstancestateUIStatus.

// The bundle object is also passed in the oncreate method.

}

 

// InVisibleCalled before service life.

@ Override

Public void onrestart (){

Super. onrestart ();

// Load the changes. ThisActivityAlready visible.

}

 

// InVisibleLife cycle.

@ Override

Public void onstart (){

Super. onstart ();

// Required by the applicationUIChange. Now,ActivityVisible.

}

 

// InActiveLife cycle.

@ Override

Public void onresume (){

Super. onresume ();

// Resume pausedUIUpdate, thread, or whenInactiveThe process to be paused.

}

 

// InActiveEnd of Life call to saveUIStatus change.

@ Override

Public void onsaveinstancestate (bundle savedinstancestate ){

// SaveUIThe status changes to savedinstancestate.

// When the process is killed or restarted, the bundle is passed into the oncreate method.

Super. onsaveinstancestate (savedinstancestate );

}

 

// InActiveEnd of Life call.

@ Override

Public void onpause (){

// AbortUIUpdate, thread, orCPUA strong process (whenActivityNo longerActiveFront-endActivityDoes not need to be updated)

Super. onpause ();

}

 

// InVisibleEnd of Life call.

@ Override

Public void onstop (){

// AbortUIUpdate, thread, orActivityInvisible Process

// Save the data and status changes.

// When this is called, the process may be killed.

Super. onstop ();

}

 

// InFullEnd of Life call.

@ Override

Public void ondestroy (){

// Clear any resources, including closing threads and closing database connections.

Super. ondestroy ();

}

}

 

As shown in the code snippet above, when youOverrideWhen processing these functions, you must always call the functions of the parent class.