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Don't reload application when orientation changes

开发者 https://www.devze.com 2023-03-03 16:44 出处:网络
I simply need nothing to change when the screen is rotated. My app displays a random image when it first loads and rotating the device should not select another random image.

I simply need nothing to change when the screen is rotated. My app displays a random image when it first loads and rotating the device should not select another random image. H开发者_JS百科ow can I (simply) make this behavior stop?


There are generally three ways to do this:

  1. As some of the answers suggested, you could distinguish the cases of your activity being created for the first time and being restored from savedInstanceState. This is done by overriding onSaveInstanceState and checking the parameter of onCreate.

  2. You could lock the activity in one orientation by adding android:screenOrientation="portrait" (or "landscape") to <activity> in your manifest.

  3. You could tell the system that you meant to handle screen changes for yourself by specifying android:configChanges="orientation|screenSize" in the <activity> tag. This way the activity will not be recreated, but will receive a callback instead (which you can ignore as it's not useful for you).

Personally I'd go with (3). Of course if locking the app to one of the orientations is fine with you, you can also go with (2).


Xion's answer was close, but #3 (android:configChanes="orientation") won't work unless the application has an API level of 12 or lower.

In API level 13 or above, the screen size changes when the orientation changes, so this still causes the activity to be destroyed and started when orientation changes.

Simply add the "screenSize" attribute like I did below:

<activity
    android:name=".YourActivityName"
    android:configChanges="orientation|screenSize">
</activity>

Now, when you change orientation (and screen size changes), the activity keeps its state and onConfigurationChanged() is called. This will keep whatever is on the screen (ie: webpage in a Webview) when the orientation changes.

Learned this from this site: http://developer.android.com/guide/topics/manifest/activity-element.html

Also, this is apparently a bad practice so read the link below about Handling Runtime Changes:

http://developer.android.com/guide/topics/resources/runtime-changes.html


You just have to go to the AndroidManifest.xml and inside or in your activities labels, you have to type this line of code as someone up there said:

android:configChanges="orientation|screenSize"

So, you'll have something like this:

<activity android:name="ActivityMenu"
android:configChanges="orientation|screenSize">
</activity>

Hope it works!


<activity android:name="com.example.abc" 
 android:configChanges="orientation|screenSize"></activity>

Just add android:configChanges="orientation|screenSize" in activity tab of manifest file.

So, Activity won't restart when orientation change.


It's my experience that it's actually better to just deal with the orientation changes properly instead of trying to shoehorn a non-default behavior.

You should save the image that's currently being displayed in onSaveInstanceState() and restore it properly when your application runs through onCreate() again.


This solution is by far the best working one. In your manifest file add

<activity
    android:configChanges="keyboardHidden|orientation|screenSize"
    android:name="your activity name"
    android:label="@string/app_name" 
    android:screenOrientation="landscape">
  </activity

And in your activity class add the following code

@Override
public void onConfigurationChanged(Configuration newConfig) 
{
    super.onConfigurationChanged(newConfig);
    if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT) {
        //your code
    } else if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
  //your code

    }
}


In manifiest file add to each activity this. This will help

android:configChanges = "orientation|keyboard|keyboardHidden|screenLayout|screenSize"


add android:configChanges="keyboardHidden|orientation|screenSize" for all the app activities tags in manifest.


Just add this to your AndroidManifest.xml

<activity android:screenOrientation="landscape">

I mean, there is an activity tag, add this as another parameter. In case if you need portrait orientation, change landscape to portrait. Hope this helps.


just use : android:configChanges="keyboardHidden|orientation"


As Pacerier mentioned,

android:configChanges="orientation|screenSize"


All above answers are not working for me. So, i have fixed by mentioning the label with screenOrientation like below. Now everything fine

<activity android:name=".activity.VideoWebViewActivity"
        android:label="@string/app_name"
        android:configChanges="orientation|screenSize"/>


http://animeshrivastava.blogspot.in/2017/08/activity-lifecycle-oncreate-beating_3.html

@Override
protected void onSaveInstanceState(Bundle b)
{
        super.onSaveInstanceState(b);
    String str="Screen Change="+String.valueOf(screenChange)+"....";
        Toast.makeText(ctx,str+"You are changing orientation...",Toast.LENGTH_SHORT).show();
    screenChange=true;

}


Prevent Activity to recreated Most common solution to dealing with orientation changes by setting the android:configChanges flag on your Activity in AndroidManifest.xml. Using this attribute your Activities won’t be recreated and all your views and data will still be there after orientation change.

<activity
    android:name="com.example.test.activity.MainActivity"
    android:configChanges="orientation|screenSize|keyboardHidden"/>

this is work for me

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