Android BadTokenException when using a WebView Container

Question

So I followed a post on avoiding WebView memory leaks, which suggests to use a webview container and then programmatically add/remove the webview from the container in activity codes: Memory leak in WebView

However, I hit the following crash when clicking on an html element which prompts a list of options to select, (e.g. date/Month drop down menu)

W/dalvikvm(17767): threadid=1: thread exiting with uncaught exception (group=0x4001d5a0)
W/WindowManager(129): Attempted to add window with non-application token WindowToken{4094b730 token=null}.  Aborting.
FATAL EXCEPTION: main
android.view.WindowManager$BadTokenException: Unable to add window -- token null is not for an application
 android.view.ViewRoot.setView(ViewRoot.java:561)
 android.view.WindowManagerImpl.addView(WindowManagerImpl.java:177)
 android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91)
 android.app.Dialog.show(Dialog.java:265)
 android.webkit.WebView$InvokeListBox.run(WebView.java:9170)
 android.os.Handler.handleCallback(Handler.java:587)
 android.os.Handler.dispatchMessage(Handler.java:92)
 android.os.Looper.loop(Looper.java:150)
 android.app.ActivityThread.main(ActivityThread.java:4263)
 java.lang.reflect.Method.invokeNative(Native Method)
 java.lang.reflect.Method.invoke(Method.java:507)
 com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
 com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
 dalvik.system.NativeStart.main(Native Method)

I have the following in my layout:

FrameLayout
    android:id="@+id/webview_container"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_below="@+id/titlebar">
/FrameLayout>

I have the following in onCreate():

mWebViewContainer = (FrameLayout)findViewById(R.id.webview_container);
mWebView          = new WebView(getApplicationContext());
mWebViewContainer.addView(mWebView);

mWebView.setWebChromeClient(new WebChromeClient());

I also set a WebViewClient.

I have verified that mWebView.getWindowToken() does return a non-null value.

Any ideas as to why this issue might be happening?

Edit: I've done some more experimenting and looking around, but still haven't solved this issue. Everything functions fine if I put the webview directly in the layout itself. But I don't want to do that because I want to be able to dynamically swap webviews.

Does the error still occur if you replace "getApplicationContext()" with "this" when you create the WebView? — Joakim Berglund, Feb 07 '12 at 20:54

score 13 · Answer 1 · answered Sep 28 '12 at 11:04

The problem is here:

    mWebView.setWebChromeClient(new WebChromeClient());

after you have left the activity, there're chances that some callbacks in WebChromeClient will try to open dialogs while the container activity has been destroyed.
Here is one solution that works for me, just add mWebView.destroy() in your activity's onDestroy()

    @Override
    public void onDestroy() {
        super.onDestroy();
        if (mWebView != null)
            mWebView.destroy();
    }

Joakim Berglund · Accepted Answer · 2012-02-07T21:00:13.930

9

When you create the WebView you are currently using the context of the application. You should be using the context of the Activity. To solve the problem, replace getApplicationContext() with this when you create the WebView.

edited Feb 07 '12 at 21:00

answered Feb 07 '12 at 20:51

Joakim Berglund

2,859
1
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shouldn't this be comment? I think you have reputation to add comment. Move to comment before someone down vote. – kosa Feb 07 '12 at 20:53
True, true. Edited the answer as I think this might solve the problem, though. – Joakim Berglund Feb 07 '12 at 21:01
Unfortunately that does not solve the problem. Same crash occurs even when using "this" – Zack Foster Feb 07 '12 at 21:03
1

I'm experiencing the same thing even though the webview is created via XML. So this does not seem to be the solution... – Tom Susel Sep 28 '13 at 19:57

Android BadTokenException when using a WebView Container

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