Develop Reference

Getting Error(Could not identify launch activity: Default Activity not found) While running project

i am getting this error while developing my app, every thing works fine suddenly this error happened while run the app and checking the changes, as i told everything works fine suddenly this happen i didn't change anything in Manifest.xml file., this is the manifest file kindly help me out.
this is the error i am getting
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.habitreminder">
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.READ_CALENDAR" />
<uses-permission android:name="android.permission.WRITE_CALENDAR" />
<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=".OnboardingPackage.OnboardingSlider"
android:theme="#style/Theme.AppCompat.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".userhome.UserDashboardActivity"
android:theme="#style/Theme.AppCompat.NoActionBar"
android:label="#string/title_activity_user_dashboard">
</activity>
<activity
android:name=".signup.UserCalenderSignupActivity"
android:theme="#style/Theme.AppCompat.NoActionBar" />
<activity
android:name=".signup.UserMapSignupActivity"
android:theme="#style/Theme.AppCompat.NoActionBar" />
<activity
android:name=".signup.UserDetailsSignupActivity"
android:theme="#style/Theme.AppCompat.NoActionBar" />
<activity
android:name=".login.LoginActivity"
android:theme="#style/Theme.AppCompat.NoActionBar" />
<activity
android:name=".LoginSignup.LoginSignupActivity"
android:theme="#style/Theme.AppCompat.NoActionBar" />
<activity
android:name=".MainActivity"
android:theme="#style/Theme.AppCompat.NoActionBar">
</activity>
<meta-data
android:name="com.google.android.geo.API_KEY"
android:value="AIzaSyCy-z3OoXACHh_MKBLoCPjdNo2ySD1ogU8" />
<meta-data android:name="com.facebook.sdk.ApplicationId"
android:value="#string/facebook_app_id"/>
<activity android:name="com.facebook.FacebookActivity"
android:configChanges="keyboard|keyboardHidden|screenLayout|screenSize|orientation"
android:label="#string/app_name" />
<activity
android:name="com.facebook.CustomTabActivity"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.BROWSABLE" />
<data android:scheme="#string/fb_login_protocol_scheme" />
</intent-filter>
</activity>
<activity android:name=".ProfileSettings.changeprofilename"
android:theme="#style/AppThemepopup"/>
</application>
</manifest>

Is your activity declared in َAndroidManifest like this ?
<activity
android:name=".launchactivity"
android:label="#string/title_activity_login"
android:windowSoftInputMode="stateHidden" />
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>

enter image description here
I just close the Android Studio And delete 2 folders name caches and tmp and start the Android Studio again and it worked.

AAPT2 error: check logs for details AppThene

I am facing an AAPT2 error, this is due to the upgrade of Android Studio.
After a lot of Internet Search, i figured it must be something with the xml in the Android Manifest. I tried different things, chanching the structre, but not sucessful yet. Do have experience with the AndroidManifest.xml and AAPT2? Here's mine
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="ch.workouttracker"
android:versionCode="1"
android:versionName="1.0" >
<!--
The ACCESS_COARSE/FINE_LOCATION permissions are not required to use
Google Maps Android API v2, but you must specify either coarse or fine
location permissions for the 'MyLocation' functionality.
-->
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="AppTheme">
<activity android:name=".TrackActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".ProfileActivity"
android:label="#string/title_activity_profile" >
</activity>
<activity
android:name=".TrackCardioActivity"
android:label="#string/title_activity_track_cardio">
<meta-data
android:name="com.google.android.geo.API_KEY"
android:value="#string/google_maps_key" />
</activity>
<activity
android:name=".TrackWorkoutActivity"
android:label="#string/title_activity_track_workout" >
</activity>
<activity
android:name=".LogoutActivity"
android:label="#string/title_activity_logout">
</activity>
<activity
android:name=".SettingsActivity"
android:label="#string/title_activity_settings" >
</activity>
<activity
android:name=".DashbordActivity"
android:label="#string/title_activity_dashboard" >
</activity>
<activity
android:name=".CreatePlanActivity"
android:label="#string/title_activity_create_plan" >
</activity>
<activity
android:name=".CreateExerciseActivity"
android:label="#string/title_activity_create_exercise" >
</activity>
<activity
android:name=".EditActivity"
android:label="#string/title_activity_edit" >
</activity>
<activity
android:name=".LoginActivity"
android:label="#string/title_activity_login" >
</activity>
<activity
android:name=".WorkoutDetailActivity"
android:label="#string/title_activity_workout_detail" >
</activity>
<activity
android:name=".PlanDetailActivity"
android:label="#string/title_activity_plan_detail" >
</activity>
<activity android:name=".CalendarActivity" >
</activity>
<activity android:name=".EditExerciseActivity">
</activity>
</application>
</manifest>
I can't find the problem. Maybe you can.

Try #style/Apptheme instead of just Apptheme.
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">

Android Error: INSTALL_PARSE_FAILED_MANIFEST_MALFORMED

im new here (at Stackoverflow and programming android) and just gotten an error thats not covered in my education books etc. Maybe you could cover it, i would be very happy:). Something went wrong with my Manifest thats covered in app->search->main. Heres the Code. One Error is Android Studio showing me at line 92: cause theres no constructor but i guess thats not neccessary.. (i got this error to when i want to install it even when i delete this).
So here it is :
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="de.plaetzmueller.yourworkoutplanner">
<!-- To auto-complete the email text field in the login form with the user's emails -->
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.READ_PROFILE" />
<uses-permission android:name="android.permission.READ_CONTACTS" />
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity
android:name=".LoginScreen"
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=".HomeActivity" />
<activity android:name=".ActiveWorkout"
android:label="#string/ActiveWorkout"
android:parentActivityName=".HomeActivity">
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value=".HomeActivity" />
</activity>
<activity android:name=".AddAWorkoutScreen"
android:label="#string/AddWorkoutPlan"
android:parentActivityName=".HomeActivity">
<meta-data
android:name="android.support.PARENT_ACTIVITY"/>
</activity>
<activity android:name=".Excercises"
android:label="#string/Excercises"
android:parentActivityName=".HomeActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value=".HomeActivity"/>
</activity>
<activity android:name=".ProgressScreen"
android:label="#string/Progress"
android:parentActivityName=".HomeActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value=".HomeActivity"/>
</activity>
<activity android:name=".VideoScreen"
android:label="#string/Videos"
android:parentActivityName=".HomeActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value=".HomeActivity"/>
</activity>
<activity android:name=".FriendList"
android:label="#string/Friends"
android:parentActivityName=".HomeActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value=".HomeActivity" />
</activity>
<activity android:name=".TrophyActivity"
android:label="#string/Trophys"
android:parentActivityName=".HomeActivity">
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value=".HomeActivity"/>
</activity>
<activity android:name=".SeeMoreActivity"
android:label="#string/SeeMore"
android:parentActivityName=".HomeActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value=".HomeActivity"/>
</activity>
<activity android:name=".SQLHelper" />
<activity android:name=".VideoScreenNutrion" />
<activity android:name=".VideoScreenExerciseExecution" />
<activity android:name=".VideoScreenStretchingAndWarmingUp" />
<activity android:name=".VideoScreenHowTo"></activity>
</application>
</manifest>

Please check that classes which you've registered as activities really extend Activity. At least I'd be surprised if .SQLHelper is instance of Activity. Than remove all redundant declarations.

Adding <meta-data> tags to manifest file causes namespace error?

When I add <meta-data> tags to my manifest file the app refuses to run and throws a ManifestMergerFailureException aswell as a org.w3c.dom.DOMException.
Manifest without tags:
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<application
android:name=".StarterApplication"
android:allowBackup="true"
android:icon="#mipmap/sf"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".LoginActivity"
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=".TimelineActivity"
android:label="#string/title_activity_timeline" >
</activity>
<activity
android:name=".RegisterActivity"
android:label="#string/title_activity_register" >
</activity>
</application>
Manifest with <meta-data> tags, generates namespace error:
<application
android:name=".StarterApplication"
android:allowBackup="true"
android:icon="#mipmap/sf"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<meta-data
android:name="com.parse.APPLICATION_ID"
android:="APPKEY" />
<meta-data
android:name="com.parse.CLIENT_KEY"
android:value="CLIENTKEY" />
<activity
android:name=".LoginActivity"
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>

android:="APPKEY" />
Class "value" missing ;)

I can't see my app in the list of recently opened Android apps

When I pressed home button on my android device, my app should appear on recent app but I can't see it.
And this is my manifest file :
<?xml version="1.0" encoding="utf-8"?>
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<application
android:name="com.hu.restaurantfinalproject.graduationProject.Libraries_Classes.AppController"
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.hu.restaurantfinalproject.graduationProject.Activities.getDataItems"
android:label="#string/app_name" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.hu.restaurantfinalproject.graduationProject.Activities.FilterActivity" />
</activity>
<activity
android:name="com.hu.restaurantfinalproject.graduationProject.Activities.AddR"
android:label="#string/title_activity_add_r" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.hu.restaurantfinalproject.graduationProject.Activities.getDataItems" />
</activity>
<activity
android:name="com.hu.restaurantfinalproject.graduationProject.Activities.RatingAndComment"
android:label="#string/title_activity_rating_and_comment" >
</activity>
<activity
android:name="com.hu.restaurantfinalproject.graduationProject.Activities.FilterActivity"
android:label="#string/title_activity_filter"
>
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.hu.restaurantfinalproject.graduationProject.Activities.AddL"
android:label="#string/title_activity_add_lawyer" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.hu.restaurantfinalproject.graduationProject.Activities.getDataItems" />
</activity>
<activity
android:name="com.hu.restaurantfinalproject.graduationProject.Activities.ShowFullImageItem"
android:label="#string/title_activity_show_full_image_item" />
<activity
android:name="com.hu.restaurantfinalproject.graduationProject.Activities.AddD"
android:label="#string/title_activity_add_doctor" >
</activity>
</application>
Please help!
When I pressed home button on my android device, my app should appear on recent app but I can't see it.

Be sure that your android:label="#string/title_activity_filter" is defined properly.