WebView doesn't show JSAlert on Lollipop devices

Question

It wasn't showing JSAlert on any devices. And then I set a WebChromeClient:

webView.setWebChromeClient(new WebChromeClient() {

            @Override
            public boolean onJsAlert(WebView view, String url, String message,
                    JsResult result) {
                return super.onJsAlert(view, url, message, result);
            }

            @Override
            public boolean onJsPrompt(WebView view, String url, String message,
                    String defaultValue, JsPromptResult result) {
                return super.onJsPrompt(view, url, message, defaultValue,
                        result);
            }

        });

Now it works fine on all pre-Lollipop devices. And doesn't show any alert on Lollipop devices.

Logcat says "Cannot create a dialog, the WebView context is not an Activity".

See [Showing an AlertDialog from a Webview outside of an Activity](http://stackoverflow.com/questions/26044179/showing-an-alertdialog-from-a-webview-outside-of-an-activity) post probably help — ρяσѕρєя K, Apr 09 '15 at 05:54
@ρяσѕρєяK I ve already come across this. It didn't help. Gives the same same result. I actually put breakpoints in onJSAlert method to check if it's actually called. And it didn't. — Seshu Vinay, Apr 09 '15 at 06:01
@SeshuVinay Does the debugger pass through the line `return super.onJsPrompt(view, url, message, defaultValue, result);` ? If yes, remove the super invocation and put a custom Dialog using the context of your outer activity. — bonnyz, Apr 13 '15 at 16:40

score 4 · Accepted Answer · answered Apr 20 '15 at 11:48

4

There is a bug introduced in version 40 of WebView, and is fixed in version 42.

Check the issue reported at

https://code.google.com/p/chromium/issues/detail?id=478204

answered Apr 20 '15 at 11:48

Pavan Andhukuri

1,547
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score 0 · Answer 2 · answered Apr 14 '15 at 09:29

It needs to require a permission first

<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />

If you are using Jscript for opening in webview. You can create Dialog like this write this code in your jscript

<input type="button" value="Display dialog" onClick="displayDialog()" />
    <script>
        function displayDialog() {
            //alert("Javascript Dialog");
            Android.showDialog();
        }
    </script>
</input>

OR a very simple way to create a dialog in webview

webView.setWebChromeClient(new WebChromeClient() {
        @Override
        public boolean onJsAlert(WebView view, String url, String message, JsResult result) {
            mResult = result;
            AlertDialog dialog = new AlertDialog.Builder(MyService.this)
                    .setTitle("test Dialog")
                    .setMessage("This is test dialog")
                    .setOnCancelListener(new CancelListener())
                    .setNegativeButton("Cancel", new CancelListener())
                    .setPositiveButton("Ok", new PositiveListener())
                    .create();
            dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);
            dialog.show();

            return true;
        }
    });

One last thing if these above doesn't work You need to create custom dialog in Layout pro-grammatically and add your view in this. Like

WindowManager windowManager = (WindowManager) getSystemService(WINDOW_SERVICE);

WindowManager.LayoutParams params = new WindowManager.LayoutParams(
                WindowManager.LayoutParams.WRAP_CONTENT, 
                WindowManager.LayoutParams.WRAP_CONTENT
                WindowManager.LayoutParams.TYPE_PHONE,
                0,
                PixelFormat.TRANSLUCENT);

params.gravity = Gravity.CENTER;

windowManager.addView(yourView, params);

if that html page is dynamic, how can we implement this. that s the problem. it is not a local file to add js Function in that. I just need to enable alert window for the webview, not for local file. — Tamilselvan Kalimuthu, Apr 14 '15 at 09:52
Exactly. Mine is a bank page that comes in a payment gateway. I cant edit that — Seshu Vinay, Apr 14 '15 at 10:38
Why the type of the Window must be set to WindowManager.LayoutParams.TYPE_SYSTEM_ALERT ? The dialog shows up on top of the WebView perfectly fine without that in Android 5.x or 6.x — Alex Bitek, Mar 29 '16 at 12:00

score 0 · Answer 3 · answered Apr 14 '15 at 12:35

0

Please share the code that you are using to construct the WebView. It sounds like you are constructing it with a Service or Application Context rather than an Activity.

Please try using an Activity context.

answered Apr 14 '15 at 12:35

ksasq

4,424
2
18
10

1

https://code.google.com/p/chromium/issues/detail?id=447607 i am using activity context only , this issue exists only in the latest update in android system webview, i am searching solution for this issue. – Tamilselvan Kalimuthu Apr 14 '15 at 13:45
I second @TamilselvanKalimuthu. Issue is with prelollipop devices. seems to be a bug in the latest android. – Seshu Vinay Apr 15 '15 at 09:23
I see, thanks for the clarification. Can you try with the latest beta build of WebView in the Google Play Store? For details please see https://plus.google.com/u/0/communities/105434725573080290360 – ksasq Apr 17 '15 at 16:02

WebView doesn't show JSAlert on Lollipop devices

3 Answers3