Develop Reference

My application icon doesn't appear when I debug or Run 'app' on android studio, what happened?

My application icon no longer appears on my android phone screen when I debug like it used to. I know this has something to do with the androidmanifest.xml file. I've looked up several solutions for me but those solutions resulted in my application being unable to even run in the first place.
What could be the problem here?
I have tried the solutions mentioned here:
Android Studio: App icon doesn't appear in the home screen or app list
Launcher icon missing in Android
This is my android manifest file:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="sg.edu.singaporetech.teamproject">
<uses-permission android:name="android.permission.INTERNET" /> <!-- allow usage of camera for Android -->
<uses-permission android:name="android.permission.FOREGROUND_SERVICE"/> <!-- to run foreground service for steps -->
<uses-feature
android:name="android.hardware.camera"
android:required="true" />
<application
android:name=".StepsNotification"
android:allowBackup="true"
android:icon="#drawable/exersize"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/Theme.AppCompat.Light.NoActionBar">
<activity android:name=".DispatchActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter>
<action android:name="android.intent.action.VIEW" />
</intent-filter>
</activity>
<activity android:name=".profile.editProfile"
android:screenOrientation="portrait"
android:configChanges="orientation|keyboardHidden" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".MainActivity"
android:label="#string/app_name"
android:theme="#style/AppTheme.NoActionBar"
android:screenOrientation="portrait"
android:configChanges="orientation|keyboardHidden">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".registration.RegisterActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".home.HomeActivity">
<!--<intent-filter>-->
<!--<action android:name="android.intent.action.MAIN" />-->
<!--<category android:name="android.intent.category.LAUNCHER" />-->
<!--</intent-filter>-->
</activity>
<receiver android:name=".StepsBroadcastReceiver">
<intent-filter>
<action android:name="android.intent.action.BOOT_COMPLETED"/>
<action android:name="android.net.conn.CONNECTIVITY_CHANGE"/>
</intent-filter>
</receiver>
<service android:name=".StepsService"/>
</application>
</manifest>

I think the problem is in the line,
android:icon="#drawable/exersize"
In the application tag, app icon must he placed in the mipmap folder as it meant for the app icon only. Mipmap must have all scales of the icon.

App is being divided into 3 parts

Why is this is happening? That's an code error from .xml or from Java?
That's my app, it is divided into 3 parts (every part is a layout that is also an App) and I don't know why]
This app is part of my project for college. Ive used my partners activity and then this error appeared right after the import.
Probably this error appeared because of the import. Im not sure about what I have to do now and Im really new at Android programming.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.carro.robo.mobile.ufj.approbo">
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<application
android:allowBackup="false"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme"
tools:ignore="AllowBackup,GoogleAppIndexingWarning">
<activity
android:name=".MainBluetoothActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".PairedDevices"
android:parentActivityName=".MainBluetoothActivity" >
</activity>
<activity
android:name=".DiscoveredDevices"
android:parentActivityName=".MainBluetoothActivity" >
</activity>
<activity android:name=".Tela_bemVindo">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".CriacaoQuestoes">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
That is my .xml code. Android Version: 19 (KitKat 4.4)

Your app can have more than 1 item in the launcher. Every Activity that has a launcher intent filter gets an entry in it. Yours has 3. If you don't want them to be in the launcher, remove the launcher intent filter from the ones you don't want to show up.

combining two eclipse android java applications

I'm trying to combine the functionality of BasicAccessoryDemo with AndroidWebServer (basically a USB=>Electronics interface with a simple web host app)
My java knowledge is limited at the moment and I'm running into some issues.
I tried combining the code into one project, but couldn't get it to work. I've read about adding one project to the other as a library.
Tell the BasicAccessoryDemo it's a library
Tell AndroidWebServer to include the BasicAccessoryDemo library
If I try to call a BasicAccessoryDemo method inside AndroidWebServer, I get the error 'accessoryManager cannot be resolved'. Which looks like there's no real connection between the apps?
Tried adding the BasicAccessoryDemo AndroidManifest.xml info to the AndroidWebServer manifest, but doesn't make a difference. Am I missing something? Sorry if this is a noob question, I've been trying to get this to work for a week now.
If anyone could point me in the right direction, that would be terrific!
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.varma.android.aws"
android:versionCode="1"
android:versionName="1.0"
android:installLocation="auto">
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-sdk android:targetSdkVersion="14" android:minSdkVersion="10"></uses-sdk>
<uses-permission android:name="android.permission.VIBRATE"></uses-permission>
<application
android:icon="#drawable/icon"
android:label="#string/app_name"
android:name="com.varma.android.aws.app.AWSApplication"
android:description="#string/app_desc" android:debuggable="true">
<activity
android:name="com.varma.android.aws.ui.AWSActivity"
android:label="#string/app_title">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.varma.android.aws.ui.AWSMessageActivity"
android:label="#string/message_title"
android:theme="#android:style/Theme.NoTitleBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
</intent-filter>
</activity>
<activity
android:name="com.varma.android.aws.ui.AWSPreferenceActivity"
android:label="#string/preference_title">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
</intent-filter>
</activity>
<service android:name="com.varma.android.aws.service.HTTPService" />
<!-- this section from BasicAccessoryDemo -->
<activity
android:name="com.microchip.android.BasicAccessoryDemo.BasicAccessoryDemo"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<!-- <category android:name="android.intent.category.LAUNCHER" /> -->
</intent-filter>
<intent-filter>
<action android:name="android.hardware.usb.action.USB_ACCESSORY_ATTACHED" />
</intent-filter>
<meta-data android:name="android.hardware.usb.action.USB_ACCESSORY_ATTACHED"
android:resource="#xml/accessory_filter" />
</activity>
<uses-library android:name="com.android.future.usb.accessory" />
</application>

Android launch icon doesn't work

I'm having problems with setting my launcher icon from my android app.
As you can see, i've named the logo logodoor.png in the folder drawable (too in drawable hdpi, ldpi, etc.), and in AndroidManifest.xml drawable/logodoor
When starting up the app, it won't show the right launch icon, but the standard no-icon-android-icon.
-> On the target device the icon isn't displayed good; like there is a logo for twitter too
thanks for your answer :)
Menno
Manifest code:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="me.menno.ghlyceum" android:versionCode="1" android:versionName="1.0.4">
<uses-permission android:name="android.permission.INTERNET"/>
<application android:icon="#drawable/logodoor" android:label="Ghlyceum OB" android:theme="#android:style/Theme.Black.NoTitleBar" android:debuggable="false">
<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=".Notes" />
<activity android:name=".Help"></activity>
<activity android:name=".Rooster"></activity>
</application>
</manifest>

are you sure you have something like this:
<application
android:icon="#drawable/logodoor"
............>
</application>

<application
android:icon="#drawable/logodoor"
android:label="#string/app_name" >
<activity
android:name="YourActivityname"
android:label="#string/title_activity_flash_file" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
This way you can put your my launcher icon in manifest.

Sometimes I've had to uninstall the app for the icon to change

<application android:icon="#drawable/icon"
android:label="#string/app_name"

How to register alternate mp3-viewer for the filebrowser app "myfiles"?

I am creating an mp3tag editor and want it to get started via the android-buildin-filebrowser "myfiles" (com.sec.android.app.myfiles/com.sec.android.app.myfiles.MainActivity) .
When i select a mp3 file i get an activity chooser that offers me two programs to execute the file.
Unfortunately my own program is not among the offered choises.
However if i use the external android-filebrowser OI File Manager it offers me a chooser
which includes my own app.
My question: how do i have to register my actrivity in the manifest so that "myfiles" can launch it?
My app is registered like this:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="media.mp3"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="7" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name" >
<activity
android:label="#string/app_name"
android:name=".Mp3TagEditorActivity" >
<intent-filter >
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
<category android:name="android.intent.category.EDIT" />
<category android:name="android.intent.category.VIEW" />
<data android:mimeType="audio/mpeg" />
</intent-filter>
</activity>
</application>
</manifest>

I am creating an mp3tag editor and want it to get started via the android-buildin-filebrowser "myfiles".
There is no "android-buildin-filebrowser 'myfiles'" in the Android OS. You may be thinking of a file browser that ships on some specific device.
My question: how do i have to register my actrivity in the manifest so that "myfiles" can launch it?
To answer that definitively, you would have to contact the author of "myfiles".
My app is registered like this:
Your <intent-filter> is rather wrong.
First, EDIT and VIEW are actions, not categories.
Second, the only way it will match on your <intent-filter> is if the LAUNCHER category is included, which is very unlikely for the EDIT or VIEW actions.
If you want this activity to both be in the home screen's launcher and respond to VIEW or EDIT actions, you would need something like this:
<activity
android:label="#string/app_name"
android:name=".Mp3TagEditorActivity" >
<intent-filter >
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter >
<action android:name="android.intent.action.EDIT" />
<action android:name="android.intent.action.VIEW" />
<data android:mimeType="audio/mpeg" />
</intent-filter>
</activity>
Two separate <intent-filter> elements are a logical OR -- any Intent that matches the first or the second will match this activity.

Actually, It may be as simple as adding:
<action android:name="android.intent.action.MUSIC_PLAYER" />
So your Manifest should look like this:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="media.mp3"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="7" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name" >
<activity
android:label="#string/app_name"
android:name=".Mp3TagEditorActivity" >
<intent-filter >
<action android:name="android.intent.action.MAIN" />
<action android:name="android.intent.action.MUSIC_PLAYER" />
<category android:name="android.intent.category.LAUNCHER" />
<category android:name="android.intent.category.EDIT" />
<category android:name="android.intent.category.VIEW" />
<data android:mimeType="audio/mpeg" />
</intent-filter>
</activity>
</application>
</manifest>
Give that a try and you may likely show up for your myfiles app. Hope that resolves your issue.