[SOLVED] "Error running app: Default Activity not Found"

"Error running app: Default Activity not Found"

I'm programming an app with sqlite+JSON, but suddenly I couldn't Run it anymore, and it popped this message, here's my AndroidManifest.xml , Idk if there's something wrong with it, my main activity is called DatosActivity, I wish you could help me.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.hitan.practica2_u3">

    <application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity
        android:name="com.example.hitan.practica2_u3.DatosActivity"
        android:theme="@style/AppTheme.NoActionBar"></activity>
</application>

</manifest>

Solution

You should add category.LAUNCHER & action.MAIN .

 <activity 
       android:name="com.example.hitan.practica2_u3.DatosActivity"
       android:theme="@style/AppTheme.NoActionBar"
          >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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