NullPointerException with ProgressBar using ActionBarCompat

Question

I'm using ActionBarCompat in support-v7-r18. When trying to show an indeterminate progress, it works on Galaxy S3 Android 4.1.2 but doesn't on Galaxy Ace Android 2.3.3.

I can't figure why.

The code raising the exception :

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    ...
    final ActionBarActivity activity = this;
    content = (WebView) findViewById(R.id.webContent);
    content.setWebViewClient(new WebViewClient() {
        @Override
        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            super.onPageStarted(view, url, favicon);
            activity.setSupportProgressBarIndeterminate(true);   <=== Line 88
            activity.setSupportProgressBarIndeterminateVisibility(true);
        }
    }

The exception :

FATAL EXCEPTION: main
    java.lang.NullPointerException
    at  android.support.v7.app.ActionBarActivityDelegateBase.updateProgressBars(ActionBarActivityDelegateBase.java:508)
    at android.support.v7.app.ActionBarActivityDelegateBase.setSupportProgressBarIndeterminate(ActionBarActivityDelegateBase.java:469)
    at android.support.v7.app.ActionBarActivity.setSupportProgressBarIndeterminate(ActionBarActivity.java:282)
    at MyActivity.onPageStarted(MyActivityActivity.java:88)
    at android.webkit.CallbackProxy.handleMessage(CallbackProxy.java:266)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:123)
    at android.app.ActivityThread.main(ActivityThread.java:3687)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:507)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625)
    at dalvik.system.NativeStart.main(Native Method)

Answer 1

Add supportRequestWindowFeature(Window.FEATURE_PROGRESS);or supportRequestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS); to onCreate() method before calling setContentView().