IllegalArgumentException when closing InAppBrowser on android

[predatorx7]

IllegalArgumentException when closing InAppBrowser on android

[breautek]

I'm not that familiar with this plugin's codebase but did some exploratory digging and

at org.apache.cordova.inappbrowser.InAppBrowser$6$1.onPageFinished (InAppBrowser.java:534)

Is when it reaches Cordova code, which is a part that calls on the Android SDK.

cordova-plugin-inappbrowser/src/android/InAppBrowser.java

Lines 532 to 540 in 8ee1d38

	childView.setWebViewClient(new WebViewClient() {
	// NB: wait for about:blank before dismissing
	public void onPageFinished(WebView view, String url) {
	if (dialog != null && !cordova.getActivity().isFinishing()) {
	dialog.dismiss();
	dialog = null;
	}
	}
	});

Line 534 is the code entering the onPageFinished callback, in which Cordova tests for an existence of and attempts to dismiss() an android.app.Dialog.

The Android SDK claims that:

This method can be invoked safely from any thread.

and doesn't document any other causes for an IllegalArgumentException.

I however did find hints at SO that suggest that this exception will raise if attempting to dismiss a dialog when the Dialog is already destroyed. I think we protect ourselves by explicitly setting the dialog to null after we dismiss it, but this might not be sufficient as there are likely other user actions that can happen that can cause a dialog to be dismissed.

I think test code needs to be added to confirm that double-dismissing a dialog (or at least attempting to dismiss it while isShowing() is false) will trigger this kind of error. If it does, then adding a isShowing() condition check before dismissing might be a solution.

And if Cordova needs to clean up anything(like setting the dialog to null), I think the onStop hook should be used.