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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.

app neither installing not running on emulator

I have created My First Android Hello World on Android Studio . but when I run it on emulator , it is not running neither installing it on Emulator .. Every time is only shows session '' Error only in log .. i have done restart several times . no use ,
this is my emulator Setting
My Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.administrator.facebooklogin" >
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
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>
</application>
</manifest>
I have changed the device and skins as well , but no use i have not found proper solution for session '' error .

Since you have just started, Explore Genymotion, a faster and better alternative to Android virtual devices for Android Development.

Android application installs but not launches [duplicate]

This question already has answers here:
My android app is not being displayed in the app drawer?
(3 answers)
Closed 8 years ago.
Before labeling this as a duplicate, please read. I have successfully installed an Android application I developed on Eclipse on to two different platforms: one emulator (Blue Stacks) and one actual device. Like I said, the app installs just fine on both platforms, but it doesn't appear on the list of apps that can be launched. When I go to settings, I can see the app on the list of installed applications, and it lets me uninstall it, but not open it. I've spent hours trying every remedy online, but nothing works. My app is only one activity, so it should be simple, but this is the first app I've developed. I'll attach my manifest xml file below.
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.teamjava.theultimatetipcalculator"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="14"
android:targetSdkVersion="19" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.teamjava.theultimatetipconverter.MainActivity"
android:screenOrientation="portrait" >
</activity>
<intent-filter>
<action android:name="android.intent.action.MainActivity" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</application>

You should probably try using the same package name for the app and location of your activity.
You have:
package="com.teamjava.theultimatetipcalculator"
android:name="com.teamjava.theultimatetipconverter.MainActivity"
Try
package="com.teamjava.theultimatetipcalculator"
android:name="com.teamjava.theultimatetipcalculator.MainActivity"
or
package="com.teamjava.theultimatetipconverter"
android:name="com.teamjava.theultimatetipconverter.MainActivity"
EDIT -
Also try placing the intent filter inside the activity. This is how my manifest looks on all my apps
<activity
android:name="com.example.exampleapp.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>

Change:
<action android:name="android.intent.action.MainActivity" />
to:
<action android:name="android.intent.action.MAIN" />

Have you checked your console in Eclipse? Sometimes, your program can compile fine, but display errors in the console on startup.
In Eclipse. Window - show view - Console

Can't install APK correctly on device

I have built & sign my apk by Eclipse ADT as it is describes (export and sign by creating a new key). But it can't be install on real device while an errors occurs, such as "installer package error". I have no Android device & sent my apk to friends by email. I'm using AVD and everyth is fine with it. Any suggestions? Thanx guys.
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.XXXX.YYYY"
android:versionCode="0"
android:versionName="0.9.2" android:installLocation="internalOnly">
<uses-sdk
android:minSdkVersion="13"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme"
android:hardwareAccelerated="true"
android:permission="android.permission.INTERNET"
android:allowBackup="true">
<activity
android:name="com.XXXX.YYYY.ActivityMain"
android:label="#string/main_activity_title"
android:launchMode="singleTop" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="com.XXXX.YYYY.ActivityDetails"
android:parentActivityName="com.XXXX.YYYY.ActivityMain"
android:excludeFromRecents="true"
android:configChanges="orientation|screenSize">
</activity>
</application></manifest>
UPD: apk installs good, but the error occurs if choose Open (see screenshot). After that app works fine. But on tablet if try open app it says "App deleted".
UPD2: add supporting API 4+ meta tag for the 2nd activity, but it takes no effect
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.XXXX.YYYY.ActivityMain" />

You probably need to make sure your device and your friend's devices can install apps that are not from the play store.
This is a feature you have to specifically set, or else apps that are outside the play store will not install.
Here is how to set it:
Open settings
Find the Security settings (Pre 4.0 it is under Applications)
Look for a setting that says Unknown sources, or non-market apps
Enable that setting
Everything should work after that!
Here is an article with pictures if you are still confused :)

Your example was missing the closing </manifest> and android:enabled. I'm not sure if the latter would prevent a device from fully installing it but the first one would.
I've also had issues using the full activity names in the past, so you may want to try using simplifying them to see if it helps.
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.XXXX.YYYY"
android:versionCode="0"
android:versionName="0.9.2" android:installLocation="internalOnly">
<uses-sdk
android:minSdkVersion="13"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme"
android:hardwareAccelerated="true"
android:allowBackup="true">
<activity
android:name=".ActivityMain"
android:label="#string/main_activity_title"
android:enabled="true"
android:permission="android.permission.INTERNET"
android:launchMode="singleTop" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".ActivityDetails"
android:parentActivityName=".ActivityMain"
android:excludeFromRecents="true"
android:configChanges="orientation|screenSize">
</activity>
</application>
</manifest>

Is "Unknown sources" option under "security" allowed on device?

My problem was a duplicate internet permission request on Manifest! When I remove that from activity app was run normally.

Uninstalling Android Application

When I create an Android project in Eclipse and send it to my device for debugging, the app works fine but when I try to uninstall it, I get a strange message. Below are the steps to recreate my problem:
Eclipse Version: 4.2.0 Build id: I20120608-1400
ADT Version: 2.0.3 v201208082019-427395
Run Eclipse
Click File->New->Project...
Select Android/Android Application Project
Click Next.
Enter Application Name: Test
Build SDK: Android 4.1
Minimum Required SDK: API 8 Android 2.2
Enable: Create custom launcher icon / Create project in workspace
Click Next thrice.
Click Finish.
Connect 4.1 Android device to computer via USB.
Click Run->Run from menu.
Select "Android application" on popup the "Run As" popup.
Click Ok.
MainActivity application runs on device.
Click the Back button on the Android device.
Open applications on device and find "MainActivity" app.
Long press the MainActivity icon and drag to trash.
Here's the puzzling part:
Instead of getting a standard
Do you want to uninstall this app?
I get a dialog with this text:
MainActivity is part of the following app: Test
Do you want to uninstall this app?
Why do I get this message instead of the standard one?
Why is MainActivity the name of the app when I specifically stated the name of the app is "Test"?
Additional Information:
If I go to Settings->Apps, the Application shows up as Test but is listed in my Launcher as MainActivity.
AndroidManifest.xml
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.test"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/title_activity_main" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>

The solution is to remove android:label="#string/title_activity_main" in the activity element.
The AndroidManifest.xml below solves the problem on Android 4.1.1 .
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.test"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>

Make sure your app name app_name is not styled.
Since I was using the app name somewhere else in the app I had made it bold, like this - In my strings.xml
<string name="app_name"><b>We are sons<b></string>
When I removed
<b></b>
tags, it worked.
Just keep it :
<string name="app_name">We are sons</string>

I do not know how to solve the first issue but the second can be solved in the following way. The problem is connected with Android new project wizzard. To solve this problem you can correct your manifest file in the following way and redeploy your project:
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.test"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/title_activity_main" >
<intent-filter android:label="#string/app_name" >
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
Do not forget to check what is the value of app_name. Some more details you can find in this post