How to logout from a website running in an Android Webview?

Question

This is my code for handling login:

wblogin.getSettings().setJavaScriptEnabled(true);

wblogin.loadUrl("http://mywebsite.com/login.php");

wblogin.setWebViewClient(new WebViewClient() {
    @Override
    public void onPageFinished(WebView view, String url) {
        wblogin.loadUrl("javascript: {" +
            "document.getElementById('email').value = '" + user_name + "';" +
            "document.getElementById('password').value = '" + pass_name + "';" +
            "document.getElementById('xyz').click();" +
        "};");
    }
});

When I logout from the website running in Webview it starts to login automatically

score 0 · Answer 1 · answered Nov 15 '17 at 17:53

Have you turned on a setting like "Remember my login" for the login page? Maybe it is a default checkbox set?

Second idea: Maybe the auto login after logout happens because of cookies set. Find information how to disable cookies in a webview here and here

score 0 · Answer 2 · answered Jan 23 '22 at 10:58

There is no really pretty and short way in doing so.
The problem is that everytime you load a new page you run the code for logging in on every single page.
To work around that problem you should save wether you already logged into the application, simplest approach is as follows:

 wblogin.setWebViewClient(new WebViewClient() {
        private boolean shallLogin = true;

        @Override
        public void onPageFinished(WebView view, String url) {
            if (shallLogin == true) {
                wblogin.loadUrl("javascript: {" +
                "document.getElementById('email').value = '" + user_name + "';" +
                "document.getElementById('password').value = '" + pass_name + "';" +
                "document.getElementById('xyz').click();" +
                "};");
                shallLogin = false;
            }
        }

    });

As the login might fail or the user might move around without being logged in a more proper way would be to register a JS Callback and on page reload check if the login were successful by finding an element by ID which is only visible when logged in like the userimage or something.

...
    @Override
    public void onPageFinished(WebView view, String url) {
    wblogin.loadUrl("javascript: {" +
        "window.ANDROID_CALLBACK.login(document.getElementsByClassName('.my-user-img').length > 0);"
        "};");
    }

...

    class LoadListener {
        public LoadListener (MyWebViewClient myWebViewClient) {
        }
        public void login(boolean loginWorked) {
            wblogin.shallLogin = !loginWorked;
        }
    }

...

    wblogin.addJavascriptInterface(new LoadListener(wblogin), "ANDROID_CALLBACK")

How to logout from a website running in an Android Webview?

2 Answers2