On Sep 21, 6:11 pm, "Mark Murphy" <[email protected]> wrote: > > I made an example that sleeps inside the Runnable. The entire WebView > > becomes unresponsive! What is the proper way (if any) of implementing > > a long-running JavaScript call? > > Everything is fine except for sleeping in the Runnable. The Runnable is > run on the UI thread -- sleeping on the UI thread, like sleeping on the > job, is not a good idea. > > If you want something that will run for a long time, use a background > thread, perhaps in the form of an AsyncTask.
Thanks for the tip. I forgot that the Handler executes Runnables on the UI thread. I thought instead that it was like an Executor. > > Is it safe to call loadUrl() from multiple threads? > > I have not tried it, but I doubt it. If you use AsyncTask, do your > loadUrl() in onPostExecute(). I found that loadUrl() is not safe to be called using AsyncTask. onPostExecute() is not called by the "main" thread, but by "WebViewCoreThread". This breaks if a text box is in use, which needs to run in "main." The solution is to manually use a Handler. 09-22 20:01:19.943: ERROR/AndroidRuntime(768): Uncaught handler: thread WebViewCoreThread exiting due to uncaught exception 09-22 20:01:20.113: ERROR/AndroidRuntime(768): android.view.ViewRoot $CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views. 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.view.ViewRoot.checkThread(ViewRoot.java:2440) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.view.ViewRoot.invalidateChild(ViewRoot.java:522) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.view.ViewRoot.invalidateChildInParent(ViewRoot.java:540) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.view.ViewGroup.invalidateChild(ViewGroup.java:2332) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.view.View.invalidate(View.java:4437) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.view.View.onFocusChanged(View.java:2428) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.widget.TextView.onFocusChanged(TextView.java:6211) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.widget.AutoCompleteTextView.onFocusChanged (AutoCompleteTextView.java:767) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.view.View.clearFocusForRemoval(View.java:2346) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.view.ViewGroup.removeViewInternal(ViewGroup.java:2034) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.view.ViewGroup.removeViewInternal(ViewGroup.java:2027) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.view.ViewGroup.removeView(ViewGroup.java:1975) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.webkit.TextDialog.remove(TextDialog.java:395) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.webkit.WebView.clearTextEntry(WebView.java:1374) 09-22 20:01:20.113: ERROR/AndroidRuntime(768): at android.webkit.WebView.loadUrl(WebView.java:1116) --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~----------~----~----~----~------~----~------~--~---
