Why two of my onClick() buttons crashes app

I am teaching myself coding by making an app.

I have a minimal functioning snake game in one project https://github.com/byn3/BynSnake

My goal is to put that working snake app into an onClick() button of my app that I’m making to learn stuff https://github.com/byn3/BryanLeungApp.

My question is, how do I get the last button (the onClick “Play Snake” to stop crashing the app?

The blue “Play Snake” button that I have crashes the app when clicked. I copied over the two classes, “SnakeActivity” and “SnakeView” and modified some other stuff. My suspect is that there is something wrong with my call to start activity

public void SnakeActivity(View view) {
    Intent i = new Intent(this, SnakeActivity.class);
    startActivity(i);
}

Or that my AndroidManifest folder is incorrect in making the activity

<activity
    android:name=".SnakeActivity"
    android:screenOrientation="landscape"
    android:theme="@android:style/Theme.NoTitleBar.Fullscreen">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>

I’ve been doing side by side code comparisons in both projects but I finally decided to make an account and ask for help because I have been stuck on this for too long and the answer might probably be something out of my scope of knowledge.

The reason is in your AndroidManifest.xml file. SnakeActivity should use AppComat theme. Try using Theme.AppCompat.Light.NoActionBar instead of @android:style/Theme.NoTitleBar.Fullscreen

And here is the log:

Process: com.example.android.bryanleung, PID: 2832
                                                 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.android.bryanleung/com.example.android.bryanleung.SnakeActivity}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
                                                     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2684)
                                                     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2751)
                                                     at android.app.ActivityThread.-wrap12(ActivityThread.java)
                                                     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1496)
                                                     at android.os.Handler.dispatchMessage(Handler.java:102)
                                                     at android.os.Looper.loop(Looper.java:154)
                                                     at android.app.ActivityThread.main(ActivityThread.java:6186)
                                                     at java.lang.reflect.Method.invoke(Native Method)
                                                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:889)
                                                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:779)
                                                  Caused by: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
                                                     at android.support.v7.app.AppCompatDelegateImplV9.createSubDecor(AppCompatDelegateImplV9.java:359)
                                                     at android.support.v7.app.AppCompatDelegateImplV9.ensureSubDecor(AppCompatDelegateImplV9.java:328)
                                                     at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:280)
                                                     at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:145)
                                                     at com.example.android.bryanleung.SnakeActivity.onCreate(SnakeActivity.java:37)
                                                     at android.app.Activity.performCreate(Activity.java:6684)
                                                     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
                                                     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2637)