Develop Reference

Android loadout/layout-land onConfigurationChanged

I have a DialogFragment in my Android app, and I need to set android:configChanges="orientation|screenSize, I want to load different layout for my DialogFragment in portrait or landscape, but now Android will not automatically do this for me, I think I need to update the layout in onConfigurationChanged , but I don't know how to do it, any sample code will be better, thank you!

Another 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.
try this code and changed your configuration :
<activity
android:name="com.example.test.activity.MainActivity"
android:configChanges="orientation|screenSize|keyboardHidden"/>
This attribute informs to Android system that you are going to handle orientation and screenSize changes for this Activity. So instead of destroying and recreating your Activity, Android will just rotate the screen and invoke one of the lifecycle callback method which is onConfigurationChanged(Configuration).
try this

I finnally find my solution, but I think it maybe only work for my situation, my situation is I want to show a imageView in portrait and not show in landscape, so I set the visibility as visiable or gone in function onConfigurationChanged' and it works

Device orientation lock causes problems

I got an app that is locked in landscape orientation. Now, when I change the devices settings to set its orientation locked to portrait, some problems occur.
After a bit of testing, it seems that for each Activity that is started, the onCreate is called twice.
First time for portrait orientation, second time as an orientationChange with orientation set to landscape. The first orientation is wrong, and probably has something to do with the device being locked to portrait.
In the app, the orientation is forced to landscape programmatically (using setRequestedOrientation), and I prefer to keep it that way, if possible, for various reasons.
Any ideas about how to avoid this behavior?
Thanks in advance!

Ok, I found a solution myself.
After a lot of searching and digging in the code, the solution was fairly simple.
All I had to do was add:
android:configChanges="orientation|screenSize"
... to all my Activities in the manifest file.
This tells the app that I will handle configuration changes myself in the code. Instead of doing this, I didn't add any handlers for these config changes. This way, my Activities aren't recreated when the orientation change happens at the creation of those Activities. I can do it this way, because my app is locked in a certain orientation.
This post came closest to my problem, but it's solution didn't work for me:
Android: set activity orientation BEFORE onCreate, but not in manifest (HDMI plugged in issue)
This post gave me the answer:
http://www.acnenomor.com/1053172p1/oncreate-were-called-twice-after-implementing-setrequestedorientation

Try setting up the orientation directly in the manifest instead of programmatically. Under your activity tag in AndroidManifest.xml add android:screenOrientation="landscape".
This should force the activity to be directly created in the correct orientation.

Android onConfigurationChanged() only in certain cases

I have stumbled on a problem, that, when the screen turns off while being in LANDSCAPE orientation, certain devices "rotate" the app back to PORTRAIT position (because the lockscreen is PORTRAIT only or something like that). I did a little research before posting this, and most popular work-around is to modify app's configuration change process to prevent activity being recreated after the configuration has changed.
But disabling activity recreation is not a solution for me, because my app supports both orientations with sepparate layout's etc.
So i would like to find out, is it possible to disable the configuration change only in special cases (Screen turned off and orientation is landscape)? Or is the right way to override onConfigurationChanged() then manually manage activity recreation inside that function (i guess simply setting different layout resources when orientation is changed simply wont cut it)?

Or is the right way to override onConfigurationChanged() then manually manage activity recreation inside that function?
Yes to an extent.
You cannot set the configChanges attribute programmatically. I guess it's to do with the way an Activity is created. They're created from the XML first and then the overridden methods in your activity implementation are invoked. There's nothing in the API that lets you change the configChanges attribute.
Now in your case it doesn't sound like you need to. If you support both orientations, then if the user locks the device and it rotates back why does it matter? From a UX perspective we know it's in portrait mode again. So should your app when it opens back up.

Orientation issue with landscape mode

I am displaying Timer on a screen .
After starting the Timer , I am changing the orientation from the portrait to landscape mode. In order to avoid the timer getting reset when changing from the portrait to landscape mode , I am adding the following code to the activity declaration in the manifest:
android:configChanges="orientation"
The problem I am facing is that , when the screen is switching from the portrait to landscape mode , the layout which gets displayed is same as portrait & not in landscape mode. Only a part of the screen of the landscape orientation is being occupied.
Is there any way by which we can avoid resetting the timer from changing from the portrait to landscape mode & also have a proper landscape layout?
Kindly provide your inputs.
Thanks in advance.

There is a simple way of doing this.
if you have two different layouts for landscape and portrait then let the android handle all the stuff for you. i mean do not override methods onConfigurationChange() method unless strictly required and do not add android:configChanges="orientation". just make different folders for portrait mode and landscape mode. viz. layout and layout-land....
To save present state of views use bundle. whenever orientation changes android reload activity and call onCreate() method. This saved bundle is passed in onCreate() method. Now you can retrieve views' state from this bundle.
now next question will be how to use this bundle. Then here is the quick example.
override onSavedInstanceState() method to save bundle.
Thanks.

Is there any way by which we can avoid
resetting the timer from changing from
the portrait to landscape mode?
Yes, store the value somewhere during onPause and read it during onResume.
Also have a proper landscape layout
Read up on Providing Resources, in particular table 2's "Screen orientation" section which also links to a very nice page about handling runtime changes.

All you need to do is make the manifest file set the screenOrientation="landscape"
<activity android:name=".main"
android:label="#string/app_name"
android:screenOrientation="landscape">
<intent-filter>
That turns off the auto sensor on only the form that you name to have landscape.

Fixed orientation Activity lifecycle on a slide out keypad phone

I have an Activity with a fixed orientation, android:screenOrientation="portrait" in my manifest. I noticed that when pressing Cntl-F11 on the emulator and when a user slides out the keyboard on a device the Activity is destroyed and onCreate is called.
Yet when I use a non-slide out keyboard device the Activity is never destroyed, simply because it is locked to portrait.
Why is there a difference in behavior between devices? Why is an Activity that is locked to portrait, invoking a configuration change? This is really irritating.
Edit: I also experimented with android:configChanges="orientation without any noticeable difference.

You can probably prevent this by telling Android you want to handle the configuration changes yourself via the configChanges attribute.
However, doesn't this point out why it is a bad idea to force the app to be in portrait? That is really annoying on phones with a keyboard.