Develop Reference

My app doesn't show up on android studio emulator

It was all good yesterday, but right now it won't show up when I run the AVD.
Don't know if it is my AndroidManifest.xml file which is pretty standard.
<?xml version="1.0" encoding="utf-8"?>
<manifest
xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.app" >
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme">
<activity
android:name="com.example.app.Hoved"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
This is now fixed all, thank you!
The problem was that I write Android app on Xamarin, so you use flags there instead of declaring the activity in the manifest.

You missing this 2 'lines', it's really important but just past it above (over) < application and it's will work.
<uses-sdk
android:minSdkVersion="14"
android:targetSdkVersion="21" />
This is the most basic question, you should know that before u start programming in visual studio or eclipse. Just watch some tutorials on youtube it will help you. Good Luck.

Not able to install my application on other Android devices

I have made an Android app using AndroidStudio and want to test it on different phones. I have generated the signed apk (release version) and I could successfully install the apk on my device (Nexus 5).
Then I tried to install the same apk on a Nexus 4 but it throws an error after the installation that the package installer has stopped.
Here is what my manifest file looks like
<?xml version="1.0" encoding="utf-8"?>
<application
android:permission="android.permission.WRITE_EXTERNAL_STORAGE"
android:allowBackup="true"
android:icon="#drawable/endecrypt_ico"
android:label="#string/app_name"
android:theme="#style/AppTheme">
<activity
android:name=".MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".PostSubmission"
android:label="#string/title_activity_post_submission"
android:parentActivityName=".MainActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.psimit.encrypt.MainActivity" />
</activity>
</application>
I am not able to understand where the problem lies. Since the app works when installed via the debugger and also using the apk on my phone, I am tempted to think if I need to do something more for compatibility across Nexus 4 and Nexus 5 during the generation of the signed apk.
I would quite appreciate some pointers if someone has encountered this problem earlier. Thanks in advance.

It's a really strange issue you have. Maybe you're doing things wrong.
The permissions should be at the root of the manifest tag :
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.app">
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<application>
<activity
...
</activity>
</application>
</manifest>

App Not Showing in Apps

I'm debugging using my Samsung Galaxy S5 and every time I run it through Android Studio it works fine and it pops up the app, but then when I click out of it it doesn't show in all of my apps like other apps I've installed to my device. The app will show in my task manager after I close out of it but it still won't show in all of my apps. Really could use some help on this one, thanks.
This is my manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="us.bisonsoftware.tab" >
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="Husky Athletics"
android:theme="#style/CustomActionBarTheme">
<activity
android:name=".TabBarExample"
android:label="Husky Athletics"
android:icon="#drawable/ic_launcher">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<data android:scheme="geo"/>
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".FirstTab" />
<activity android:name=".SecondTab" />
<activity android:name=".ThirdTab" />
</application>
<uses-permission android:name="android.permission.INTERNET" ></uses-permission>
<uses-permission android:name="android.permission.CALL_PHONE"></uses-permission>

Try to make your activity name complete like this:
<activity
android:name="com.example.myapp.TabBarExample"
... >
</activity>
I dont know your package name. You have to fill it by yourself.

Eclipse with android NoClassDefFoundError

I have tried everything to get this to work and now I have this error:
Exception in thread "main" java.lang.NoClassDefFoundError: android/app/Activity
There is another post on here that says to try this in the manifesto:
uses-library android:name="com.google.android.maps"
uses-permission android:name="android.permission.INTERNET"
This solution does not work for me.
As background, I am running one windowsXP, I had to change the Bootstrap Entries to JRE System Library and JUnit3 to fix another error. I also had to change the path for the emulator to run as well.
This is my first time trying to run the droid app stuff on here. I am using the hello world example. I assume I must run the emulator for the phone first then run my code?
Thanks
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="edu.rit.cs.ats"
android:versionCode="1"
android:versionName="1.0">
<uses-sdk android:minSdkVersion="8" />
<application android:icon="#drawable/icon" android:label="#string/app_name">
<activity android:name=".AndroidTestActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<uses-library android:name="com.google.android.maps" />
<uses-permission android:name="android.permission.INTERNET" />
</application>
</manifest>

APK Deployment Issue

I have been able to create a *.apk file from my code, place the file
in IIS, and download it onto a number of Android phones. Upon the
install, the application works exactly as expected.
However, after a phone is rebooted, the application name is changed to
the fully-qualified Java class name of the activity in the menu (so
"MyActivity" becomes "com.mycompany.MyActivity"), and when I try to go
to Menu > Settings, I get an error that causes android to force close
my application.
Looking into DDMS, I see that I get an error indicating that it can
not find my Preferences activity, despite the fact upon initial
install, it works properly.
I'm using Eclipse on Windows XP, and have several Android devices at
my disposal to test with.
Any idea what's going on?
AndroidManifest.xml:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.company.app"
android:versionCode="1"
android:versionName="1.0">
<application android:icon="#drawable/logo" android:label="#string/app_name"> <!--android:debuggable="true">-->
<activity android:name="com.company.app.ActivityMain"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="com.company.app.Preferences"
android:label="#string/app_settings">
<intent-filter>
<category android:name="android.intent.category.PREFERENCE"></category>
<action android:name="android.intent.action.MAIN"></action>
</intent-filter>
</activity>
<service android:name="com.company.app.Service"></service>
</application>
<uses-sdk android:minSdkVersion="3" />
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
</manifest>

So I finally got this to work. I think that the package installer on the HTC Hero (and maybe the HTC Droid Eris) has some issues.
I uninstalled my application from the phone, changed the name of my main activity, and re-deployed it onto the Hero. I started to immediately get a "Force Close." I connected the device to DDMS and looked at the error. It was still looking for my old activity name. I factory reset the device and reinstalled the same package (with the updated name) and everything works as expected.
So it seems that the package installer is caching some part of the old manifest or something, not really sure what exactly is going on there. I may play with it some more if I get time.
I don't know if someone else could verify this problem, maybe it's something that should be taken up with HTC?

try to use this manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.company.app"
android:versionCode="1"
android:versionName="1.0">
<application android:icon="#drawable/logo" android:label="#string/app_name"> <!--android:debuggable="true">-->
<activity android:name=".ActivityMain"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".Preferences"
android:label="#string/app_settings">
<intent-filter>
<category android:name="android.intent.category.PREFERENCE"></category>
<action android:name="android.intent.action.MAIN"></action>
</intent-filter>
</activity>
<service android:name=".Service"></service>
</application>
<uses-sdk android:minSdkVersion="3" />
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
</manifest>