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Elijah Thompson
546 PointsUnfortunately, Crystal Ball has stopped.
hello everyone. i wasn't doing anything out of the ordinary, i was following the instructions and the app stopped opening after the vid where you add the black background. my log cat:
07-13 15:04:13.757: D/AndroidRuntime(3551): Shutting down VM 07-13 15:04:13.757: W/dalvikvm(3551): threadid=1: thread exiting with uncaught exception (group=0xb1ab3ba8) 07-13 15:04:13.777: E/AndroidRuntime(3551): FATAL EXCEPTION: main 07-13 15:04:13.777: E/AndroidRuntime(3551): Process: com.example.crystalball, PID: 3551 07-13 15:04:13.777: E/AndroidRuntime(3551): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.crystalball/com.example.crystalball.MainActivity}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity. 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195) 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245) 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.app.ActivityThread.access$800(ActivityThread.java:135) 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196) 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.os.Handler.dispatchMessage(Handler.java:102) 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.os.Looper.loop(Looper.java:136) 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.app.ActivityThread.main(ActivityThread.java:5017) 07-13 15:04:13.777: E/AndroidRuntime(3551): at java.lang.reflect.Method.invokeNative(Native Method) 07-13 15:04:13.777: E/AndroidRuntime(3551): at java.lang.reflect.Method.invoke(Method.java:515) 07-13 15:04:13.777: E/AndroidRuntime(3551): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779) 07-13 15:04:13.777: E/AndroidRuntime(3551): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595) 07-13 15:04:13.777: E/AndroidRuntime(3551): at dalvik.system.NativeStart.main(Native Method) 07-13 15:04:13.777: E/AndroidRuntime(3551): Caused by: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity. 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.support.v7.app.ActionBarActivityDelegate.onCreate(ActionBarActivityDelegate.java:111) 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.support.v7.app.ActionBarActivityDelegateICS.onCreate(ActionBarActivityDelegateICS.java:58) 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.support.v7.app.ActionBarActivity.onCreate(ActionBarActivity.java:98) 07-13 15:04:13.777: E/AndroidRuntime(3551): at com.example.crystalball.MainActivity.onCreate(MainActivity.java:15) 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.app.Activity.performCreate(Activity.java:5231) 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087) 07-13 15:04:13.777: E/AndroidRuntime(3551): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159) 07-13 15:04:13.777: E/AndroidRuntime(3551): ... 11 more 07-13 15:04:18.007: I/Process(3551): Sending signal. PID: 3551 SIG: 9 07-13 15:15:03.637: D/AndroidRuntime(3601): Shutting down VM 07-13 15:15:03.637: W/dalvikvm(3601): threadid=1: thread exiting with uncaught exception (group=0xb1ab3ba8) 07-13 15:15:03.717: E/AndroidRuntime(3601): FATAL EXCEPTION: main 07-13 15:15:03.717: E/AndroidRuntime(3601): Process: com.example.crystalball, PID: 3601 07-13 15:15:03.717: E/AndroidRuntime(3601): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.crystalball/com.example.crystalball.MainActivity}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity. 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195) 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245) 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.app.ActivityThread.access$800(ActivityThread.java:135) 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196) 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.os.Handler.dispatchMessage(Handler.java:102) 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.os.Looper.loop(Looper.java:136) 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.app.ActivityThread.main(ActivityThread.java:5017) 07-13 15:15:03.717: E/AndroidRuntime(3601): at java.lang.reflect.Method.invokeNative(Native Method) 07-13 15:15:03.717: E/AndroidRuntime(3601): at java.lang.reflect.Method.invoke(Method.java:515) 07-13 15:15:03.717: E/AndroidRuntime(3601): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779) 07-13 15:15:03.717: E/AndroidRuntime(3601): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595) 07-13 15:15:03.717: E/AndroidRuntime(3601): at dalvik.system.NativeStart.main(Native Method) 07-13 15:15:03.717: E/AndroidRuntime(3601): Caused by: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity. 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.support.v7.app.ActionBarActivityDelegate.onCreate(ActionBarActivityDelegate.java:111) 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.support.v7.app.ActionBarActivityDelegateICS.onCreate(ActionBarActivityDelegateICS.java:58) 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.support.v7.app.ActionBarActivity.onCreate(ActionBarActivity.java:98) 07-13 15:15:03.717: E/AndroidRuntime(3601): at com.example.crystalball.MainActivity.onCreate(MainActivity.java:15) 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.app.Activity.performCreate(Activity.java:5231) 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087) 07-13 15:15:03.717: E/AndroidRuntime(3601): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159) 07-13 15:15:03.717: E/AndroidRuntime(3601): ... 11 more 07-13 15:20:04.067: I/Process(3601): Sending signal. PID: 3601 SIG: 9
3 Answers

Ramya reddy
Courses Plus Student 1,746 Pointsthis happened to me too. I was following the instructions as is and it stopped working.

Ramya reddy
Courses Plus Student 1,746 PointsNo couldn't get it fixed. Hoping that someone in the forum will have instructions.

Elijah Thompson
546 Pointsemulator doesnt work, used my phone to run the apps

Gunjeet Hattar
14,483 PointsHere is what you need to do
The error relates to java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity
The video in treehouse uses the Theme called ** Theme.Black.NoTitleBar.Fullscreen ** . Are you using this?
If yes, then the new android update no longer supports this. However there is a work around as proposed by treehouse
1) Change your project back to using "AppTheme" like it was before in AndroidManifest.xml and the preview.
2) 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>
3) Set the background color to black in the file res/layout/activity_main.xml. The root element, RelativeLayout, is the one that makes up the whole screen. Add this line after the layout_height line but before the closing angle bracket >:
android:background="@android:color/black"
4) Change MainActivity to extend Activity, not ActionBarActivity
Hope this helps. Ask again if you have doubts.
Elijah Thompson
546 PointsElijah Thompson
546 Pointsdid you fix it?