Android Studio: Session 'app': Error Launching Activity

Question

I have a problem with Android Studio. When I run the app, I get the following error:

$ adb shell am start -n "com.ta94.xahmad.theerror/com.ta94.xahmad.theerror.MainActivity" -a android.intent.action.MAIN -c android.intent.category.LAUNCHER
Error while executing: am start -n "com.ta94.xahmad.theerror/com.ta94.xahmad.theerror.MainActivity" -a android.intent.action.MAIN -c android.intent.category.LAUNCHER
Starting: Intent { act=android.intent.action.MAIN cat=[android.intent.category.LAUNCHER] cmp=com.ta94.xahmad.theerror/.MainActivity }

Error while Launching activity

I tried every solution on StackOverflow, but nothing worked. I would like to tell you that this happens to every project, for example if I created a new project and didn't do anything but click Run, I also had the following error

I tried the following:

1. Reinstalled Android Studio
2. Updated SDK
3. Cleaned the project
4. Unchecked Instant Run
5. Rebuilt the project
6. Changed the folder of projects
7. Deleted .gradle and .idea and recreated
8. Edit Configuration > Install Flags> -r

But nothing works ...

Manifest.xml:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.ta94.xahmad.theerror">

    <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=".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>

Layout:

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.ta94.xahmad.theerror.MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

Answer 1

I has the same problem and none of recommended methods worked. Since at least in my case application still launched on emulator/phone, so I figured, that debugging still possible if you use Run->Attach debugger to android process. The problem is that it was hard to debug startup errors. In that case the following method works:

1. run->debug app (or shift+f9)
2. On phone message "Waiting For Debugger" pops up instead of launching application (don't click anything!!!!)
3. Run->Attach debugger to android process
4. Wait a bit
5. Application launches with debugger attached

That's a workaround, but worked for me. Hope that will help.

Answer 2

I had the similar Problem while debugging through my Mobile phone... I had followed number of posts but nothing worked out for me... then, I did manual uninstall of the previously installed app from Mobile manually... then all works as expected!!