04/17 15:18:59: Launching app
$ adb shell am start -n "com.example.hellonothing/com.example.hellonothing.MainActivity" -a android.intent.action.MAIN -c android.intent.category.LAUNCHER
Error while executing: am start -n "com.example.hellonothing/com.example.hellonothing.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.example.hellonothing/.MainActivity }
Error type 3
Error: Activity class {com.example.hellonothing/com.example.hellonothing.MainActivity} does not exist.

Error while Launching activity

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

    <application
        android:allowBackup="true"
        android:icon="[USER=22138]@Mipmap[/USER]/ic_launcher"
        android:label="[USER=696546]@String[/USER]/app_name"
        android:roundIcon="[USER=22138]@Mipmap[/USER]/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="[USER=19691]@Style[/USER]/AppTheme">
        <activity
            android:name=".MainActivity"
            android:label="[USER=696546]@String[/USER]/app_name"
            android:theme="[USER=19691]@Style[/USER]/AppTheme.NoActionBar">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

package com.example.hellonothing;

import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;

public class MainActivity extends AppCompatActivity {

    [USER=1021285]@override[/USER]
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

       FloatingActionButton fab = findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            [USER=1021285]@override[/USER]
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });
    }

    [USER=1021285]@override[/USER]
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    [USER=1021285]@override[/USER]
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}