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Chad Johnson
Chad Johnson
10,936 Points

"ClassCastException:java.lang.String cannot be cast to org.json.JSONObject" when attempting to sign up a new user

When I attempt to sign up a new user, I get this ClassCastException. The user is still signed up after I dismiss the error, but I would like to get it corrected so it doesn't pop up every time a new user signs up. I thought it was something wrong with my code, so I downloaded Ben's files (SignUpActivity.java and FriendsFragment.java) and used them in my project, but I still get the same exception. Any help would be greatly appreciated!

5 Answers

Navod Bopitiya
Navod Bopitiya
3,630 Points

Update to this. Not sure if it's mentioned anywhere else.

Just insert this else if block before creating the dialog

else if(e.getMessage().equals("java.lang.ClassCastException: java.lang.String cannot be cast to org.json.JSONObject")){
                    //Do nothing since friends are not yet added.

The dialog always pops up because the Friends Fragment checks for friends when none are added yet. The above else if block should get rid of the error.

Initially the app was not actually showing this error, I don't know what happened it start showing every time new user signup. I also removed the dialog because of this error and its working fine now.

Joseph Kopko
Joseph Kopko
20,827 Points

Getting the same error, I think it has something to do with the array adapter call inside of the OnResume > done:

'''ArrayAdapter<String> adapter = new ArrayAdapter<String>(EditFriendsActivity.this, android.R.layout.simple_list_item_checked, usernames);'''

The context solution recommends recasting that second String cast as <>, but not sure why. I think that is what is throwing the error when running the program.

Jon Kussmann
Jon Kussmann
Courses Plus Student 7,254 Points

I had the same issue, but just decided to remove the code that made the dialog. You can still log the error. The app will work just fine without that dialog (at least, that's what I've found).