Trigger javascript from android app

Question

I'm pretty new to android development. One of my buttons in the app, sends the user to a webpage, where the user can login into specific system.

The webpage has text boxes for username and password. Once you click on the Login button (in the webpage) it triggers a javascript to login into the system. The code triggered is: onclick="updateAction('TourAccLogin');document.main_form.submit();

The webpage form to login:

The webpage form to login

My question is: I have the username and password in the app, I want to know if I can somehow manipulate this form, the sign in automatically without user interference? Meaning, I will fill the username and password, I "click" the login button. So the user will be directed to the system right away, without having to put in the username and password.

of course, it's also my own system. I'm just trying to save the user the step of login in again (since the user logged in into the app already with the same username and password) — Mike
– Mike, Commented Mar 26, 2013 at 20:56

Chuck Spohr · Accepted Answer · 2013-03-26 21:29:42Z

1

This technique has worked for me. In my case, I'm loading a hidden field named in mElementId with a string value stored in someData, then firing its onchange event, which didn't fire on its own. I included it to show how you can stack javascript commands in a single injection. I'm sure a variant of this would work for you.

I also escaped any single quotes to prevent a javascript error. You may need to escape any other special characters, including semicolon. In my case it wasn't necessary because the data had already been cleansed.

// Copy data to element
mWebView.loadUrl("javascript:(function() { " +  
        "document.getElementById('" + mElementId + "').value = '" + 
        someData.replace("'", "\'") + "'; " +
        "document.getElementById('" + mElementId + "').onchange();" +
        "})()");

edited Mar 26, 2013 at 21:29

answered Mar 26, 2013 at 21:19

Chuck Spohr

6264 silver badges10 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Dave · Accepted Answer · 2013-03-26 21:16:06Z

You say that it is your system, so you know what is running behind the scenes to process the login. I'm not mocking, just verifying. I'm assuming you've created a view of some sort where you have the username/password prior to doing this. I'm questioning this because you ask if there is a way of manipulating the form...

That being said, send the data as you normally would to the script that processes the login. If you're using a GET then http://some.domain.com/somescript?username=mumble&password=foo. If you're using a POST then create the post args and send it. Either way, you can process the results in a webview, which would allow your existing interface to pick up where it should.

Of course, if you're using a hash for the password or salting the password, you will need to do all that prior to sending it.

Collectives™ on Stack Overflow

Trigger javascript from android app

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related