Cannot launch the app

I had this problem too! The guy who made the course gave me this solution. It worked perfectly.

Change your project back to using "AppTheme" like it was before. Then we're going to customize the AppTheme itself:

Add the following two lines to the file res/values/styles.xml inside the <style name="AppTheme"... tag:

<item name="android:windowNoTitle">true</item> <item name="android:windowFullscreen">true</item>

Here's what the whole file should look like (you can just copy/paste this if you want):

<resources>

<!--
    Base application theme, dependent on API level. This theme is replaced
    by AppBaseTheme from res/values-vXX/styles.xml on newer devices.
-->
<style name="AppBaseTheme" parent="Theme.AppCompat.Light">
    <!--
        Theme customizations available in newer API levels can go in
        res/values-vXX/styles.xml, while customizations related to
        backward-compatibility can go here.
    -->
</style>

<!-- Application theme. -->
<style name="AppTheme" parent="AppBaseTheme">
    <!-- All customizations that are NOT specific to a particular API-level can go here. -->
     <item name="android:windowNoTitle">true</item> <!-- Hides the Action Bar -->
     <item name="android:windowFullscreen">true</item> <!-- Hides the status bar -->
</style>

</resources>

Now add the following line to your RelativeLayout element:

android:background="@android:color/black"

Here's what it looks like together:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:gravity="top" android:background="@android:color/black" tools:context=".MainActivity" >

... rest of code ...

For the TextView in the center, it crashed on me when I tried to center it. For the sake of preserving sanity, copy and paste this code for your TextView in the layout file:

<TextView android:id="@+id/textView1" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center_horizontal" android:layout_centerVertical="true" android:shadowColor="@android:color/white" android:shadowRadius="10" android:textAppearance="?android:attr/textAppearanceLarge" android:textColor="#FFFFFF" android:textSize="32sp" />

If you're STILL crashing, try cleaning and rebuilding the app:

Project > Clean in Eclipse Uninstall from the emulator Run the project from Eclipse

That should fix it. Hit me up if you're having more problems!