Android screen and layout issues

Here I did a little test, before I saw something about this, until later I really met the project, the last resort to really familiar with the inside of the process.

Here I put the test source:

Testactivity.java

Package Cn.com.hrmdemo;

Import android.app.Activity;
Import android.content.res.Configuration;
Import Android.os.Bundle;
Import Android.widget.Toast;

public class Testactivity extends Activity {

@Override
protected void OnCreate (Bundle arg0) {
SYSTEM.OUT.PRINTLN ("------testactivity onCreate------");
Toast.maketext (This, "OnCreate ... ", Toast.length_short). Show ();
Super.oncreate (arg0);
Setcontentview (r.layout.test_linearlayout);
}

@Override
protected void Onrestoreinstancestate (Bundle savedinstancestate) {
SYSTEM.OUT.PRINTLN ("------testactivity onrestoreinstancestate------");
Toast.maketext (This, "Onrestoreinstancestate ... ", Toast.length_short). Show ();
TODO auto-generated Method Stub
Super.onrestoreinstancestate (savedinstancestate);
}

@Override
protected void OnStart () {
SYSTEM.OUT.PRINTLN ("------testactivity onStart------");
Toast.maketext (This, "OnStart ... ", Toast.length_short). Show ();
TODO auto-generated Method Stub
Super.onstart ();
}

@Override
protected void Onrestart () {
SYSTEM.OUT.PRINTLN ("------testactivity onrestart------");
Toast.maketext (This, "Onrestart ... ", Toast.length_short). Show ();
TODO auto-generated Method Stub
Super.onrestart ();
}

@Override
protected void Onresume () {
SYSTEM.OUT.PRINTLN ("------testactivity onresume------");
Toast.maketext (This, "Onresume ... ", Toast.length_short). Show ();
TODO auto-generated Method Stub
Super.onresume ();
}

@Override
protected void Onsaveinstancestate (Bundle outstate) {
SYSTEM.OUT.PRINTLN ("------testactivity onsaveinstancestate------");
Toast.maketext (This, "Onsaveinstancestate ... ", Toast.length_short). Show ();
TODO auto-generated Method Stub
Super.onsaveinstancestate (outstate);
}

@Override
protected void OnPause () {
SYSTEM.OUT.PRINTLN ("------testactivity onPause------");
Toast.maketext (This, "OnPause ... ", Toast.length_short). Show ();
TODO auto-generated Method Stub
Super.onpause ();
}

@Override
protected void OnStop () {
SYSTEM.OUT.PRINTLN ("------testactivity onStop------");
Toast.maketext (This, "OnStop ... ", Toast.length_short). Show ();
TODO auto-generated Method Stub
Super.onstop ();
}

@Override
protected void OnDestroy () {
SYSTEM.OUT.PRINTLN ("------testactivity ondestroy------");
Toast.maketext (This, "OnDestroy ... ", Toast.length_short). Show ();
TODO auto-generated Method Stub
Super.ondestroy ();
}

@Override
public void onconfigurationchanged (Configuration newconfig) {
SYSTEM.OUT.PRINTLN ("------testactivity onconfigurationchanged------");
Toast.maketext (this, "screen changed ... ", Toast.length_short). Show ();
TODO auto-generated Method Stub
Super.onconfigurationchanged (Newconfig);
}

}

------------------------------------------------------above is the source----------------------------------------------------------

Let's see how the demo is configured and how it works

This screen configuration is mainly in the Androidmanifest.xml, is the Android App manifest file:

<activity .....

Android:configchanges= "The way you want to configure"

>

In your activity, configure your screen and toggle mode

1). Do nothing to configure the case

A. Under normal circumstances:

07-24 08:43:59.519:i/system.out (18726):------testactivity onCreate------
07-24 08:43:59.609:i/system.out (18726):------testactivity onStart------
07-24 08:43:59.619:i/system.out (18726):------testactivity onresume------

B. In the case of switching the horizontal screen:

07-24 08:51:01.359:i/system.out (18936):------testactivity onPause------
07-24 08:51:01.379:i/system.out (18936):------testactivity onsaveinstancestate------
07-24 08:51:01.389:i/system.out (18936):------testactivity onStop------
07-24 08:51:01.399:i/system.out (18936):------testactivity OnDestroy------
07-24 08:51:01.429:d/memalloc (18936):/dev/pmem:unmapping buffer base:0x5bb4d000 size:4608000 offset:3072000
07-24 08:51:01.429:d/memalloc (18936):/dev/pmem:unmapping buffer base:0x5c8c5000 size:16531456 offset:14995456
07-24 08:51:01.449:i/system.out (18936):------testactivity onCreate------
07-24 08:51:01.579:i/system.out (18936):------testactivity onStart------
07-24 08:51:01.579:i/system.out (18936):------testactivity onrestoreinstancestate------
07-24 08:51:01.599:i/system.out (18936):------testactivity onresume------

C. Then switch back to the vertical screen:

07-24 08:51:42.669:i/system.out (18936):------testactivity onPause------
07-24 08:51:42.689:i/system.out (18936):------testactivity onsaveinstancestate------
07-24 08:51:42.699:i/system.out (18936):------testactivity onStop------
07-24 08:51:42.729:i/system.out (18936):------testactivity OnDestroy------
07-24 08:51:42.759:d/memalloc (18936):/dev/pmem:unmapping buffer base:0x5c8c5000 size:4608000 offset:3072000
07-24 08:51:42.759:d/memalloc (18936):/dev/pmem:unmapping buffer base:0x5cd2a000 size:10797056 offset:9261056
07-24 08:51:42.789:i/system.out (18936):------testactivity onCreate------
07-24 08:51:42.859:i/system.out (18936):------testactivity onStart------
07-24 08:51:42.859:i/system.out (18936):------testactivity onrestoreinstancestate------
07-24 08:51:42.879:i/system.out (18936):------testactivity onresume------

2) Configure android:configchanges= "Orientation|keyboardhidden" (Before 4.0)

A. Under normal circumstances:

07-24 08:54:05.059:i/system.out (18936):------testactivity onCreate------
07-24 08:54:05.199:i/system.out (18936):------testactivity onStart------
07-24 08:54:05.219:i/system.out (18936):------testactivity onresume------

B. In the case of switching the horizontal screen:

07-24 08:54:25.909:i/system.out (18936):------testactivity onPause------
07-24 08:54:25.919:i/system.out (18936):------testactivity onsaveinstancestate------
07-24 08:54:25.929:i/system.out (18936):------testactivity onStop------
07-24 08:54:25.949:i/system.out (18936):------testactivity OnDestroy------
07-24 08:54:25.979:d/memalloc (18936):/dev/pmem:unmapping buffer base:0x5c7c5000 size:19603456 offset:18067456
07-24 08:54:25.979:d/memalloc (18936):/dev/pmem:unmapping buffer base:0x5da77000 size:4608000 offset:3072000
07-24 08:54:26.019:i/system.out (18936):------testactivity onCreate------
07-24 08:54:26.069:i/system.out (18936):------testactivity onStart------
07-24 08:54:26.079:i/system.out (18936):------testactivity onrestoreinstancestate------
07-24 08:54:26.079:i/system.out (18936):------testactivity onresume------

C. Then switch back to the vertical screen:

07-24 08:55:02.099:i/system.out (18936):------testactivity onPause------
07-24 08:55:02.109:i/system.out (18936):------testactivity onsaveinstancestate------
07-24 08:55:02.119:i/system.out (18936):------testactivity onStop------
07-24 08:55:02.129:i/system.out (18936):------testactivity OnDestroy------
07-24 08:55:02.139:d/memalloc (18936):/dev/pmem:unmapping buffer base:0x5c7c5000 size:4608000 offset:3072000
07-24 08:55:02.139:d/memalloc (18936):/dev/pmem:unmapping buffer base:0x5cc30000 size:9216000 offset:7680000
07-24 08:55:02.179:i/system.out (18936):------testactivity onCreate------
07-24 08:55:02.249:i/system.out (18936):------testactivity onStart------
07-24 08:55:02.289:i/system.out (18936):------testactivity onrestoreinstancestate------
07-24 08:55:02.309:i/system.out (18936):------testactivity onresume------

found that the above results are not the same as the online friends, the original is a difference.

Then went to the Internet to search the information found, arrived. 4.0 later. Adding such a configuration would make the activity's life cycle not be called again

3) Configure android:configchanges= "Keyboardhidden|orientation|screensize" (After 4.0)

A. Under normal circumstances:

07-24 08:54:05.059:i/system.out (18936):------testactivity onCreate------
07-24 08:54:05.199:i/system.out (18936):------testactivity onStart------
07-24 08:54:05.219:i/system.out (18936):------testactivity onresume------

B. In the case of switching the horizontal screen:

07-24 09:08:21.639:i/system.out (19533):------testactivity onconfigurationchanged------

C. Then switch back to the vertical screen:

07-24 09:08:21.639:i/system.out (19533):------testactivity onconfigurationchanged------

Summary: It is important to configure the activity to not reload the life cycle when switching between the screen and the

4.0 ago

<activity .....

Android:configchanges= "Orientation|keyboardhidden"

>

After 4.0

<activity .....

Android:configchanges= "Keyboardhidden|orientation|screensize"

>

------------------------------------------------------Common Settings---------------------------------------------------------

1. If your app specifies that you want to display a horizontal screen,

<activity .....

android:screenorientation= "Portrait"

>

2. If your app specifies to display a vertical screen

<activity .....

android:screenorientation= "Landscape"

>

Android screen and layout issues