Prevent screen rotation on Android
I have one of my activities which I would like to prevent from rotating because I'm starting an AsyncTask, and screen rotation makes it restart.
Is there a开发者_JAVA百科 way to tell this activity "DO NOT ROTATE the screen even if the user is shaking his phone like mad"?
Add
android:screenOrientation="portrait"
or
android:screenOrientation="landscape"
to the <activity>
element/s in
the manifest and you're done.
You can follow the logic below to prevent auto rotate screen while your AsyncTask
is running:
- Store your current screen orientation inside your activity using
getRequestedOrientation()
. - Disable auto screen orientation using
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_NOSENSOR)
. - Run/execute your
AsyncTask
. - At the end of your
AsyncTask
restore your previous orientation status usingsetRequestedOrientation(oldOrientation)
.
Please note that there are several ways to access Activity
(which runs on UI thread) properties inside an AsyncTask
. You can implement your AsyncTask
as an inner class or you can use message Handler
that poke your Activiy
class.
The easiest way I found to do this was to put
this.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
within onCreate, just after
setContentView(R.layout.activity_main);
so...
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
this.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
}
In your Manifest file, for each Activity that you want to lock the screen rotation add: if you want to lock it in horizontal mode:
<activity
...
...
android:screenOrientation="landscape">
or if you want to lock it in vertical mode:
<activity
...
...
android:screenOrientation="portrait">
Rather than going into the AndroidManifest, you could just do this:
screenOrientation = getResources().getConfiguration().orientation;
getActivity().setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LOCKED);
... AsyncTask
screenOrientation = getResources().getConfiguration().orientation;
@Override
protected void onPostExecute(String things) {
context.setRequestedOrientation(PlayListFragment.screenOrientation);
or
context.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_FULL_SENSOR);
}
The only drawback here is that it requires API level 18 or higher. So basically this is the tip of the spear.
Activity.java
@Override
public void onConfigurationChanged(Configuration newConfig) {
try {
super.onConfigurationChanged(newConfig);
if (this.getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) {
// land
} else if (this.getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) {
// port
}
} catch (Exception ex) {
}
AndroidManifest.xml
<application android:icon="@drawable/icon" android:label="@string/app_name">
<activity android:name="QRCodeActivity" android:label="@string/app_name"
android:screenOrientation="landscape" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
Add the following to your AndroidManifest.xml
[ app > src > main > AndroidManifest.xml ]
<activity android:name=".MainActivity"
android:configChanges="orientation"
android:screenOrientation="portrait"/>
Example:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="xxx.zzzzzz.yyyyy">
<uses-permission android:name="A-PERMISSION" />
<application>
<activity android:name=".MainActivity"
android:screenOrientation="portrait"
android:configChanges="orientation">
</activity>
</application>
</manifest>
User "portrait"
in your AndroidManifest.xml file might seem like a good solution. But it forces certain devices (that work best in landscape) to go into portrait, not getting the proper orientation. On the latest Android version, you will get wearing an error. So my suggestion it's better to use "nosensor"
.
<activity
...
...
android:screenOrientation="nosensor">
The following attribute on the ACTIVITY in AndroidManifest.xml is all you need:
android:configChanges="orientation"
So, the full activity node would be:
<activity android:name="Activity1"
android:icon="@drawable/icon"
android:label="App Name"
android:excludeFromRecents="true"
android:configChanges="orientation">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
Add:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_NOSENSOR);
...
...
...
}
Prevent Screen Rotation just add this following line in your Manifests.
<activity
android:name=".YourActivity"
android:screenOrientation="portrait" />
This works for me.
android:screenOrientation="portrait" on application tag <application
and
<activity ... ... android:screenOrientation="locked">
If you are using Android Developer Tools (ADT) and Eclipse you can go to your AndroidManifest.xml --> Application tab --> go down and select your activity. Finally, select your preferred orientation. You can select one of the many options.
You have to add the following code in the manifest.xml file. The activity for which it should not rotate, in that activity add this element
android:screenOrientation="portrait"
Then it will not rotate.
You can try This way
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.itclanbd.spaceusers">
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".Login_Activity"
android:screenOrientation="portrait">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
Use AsyncTaskLoader to keep your data safe even if the activity changes, instead of using AsyncTask that is a better way to build apps than preventing screen rotation.
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