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Android Build a Blog Reader Android App Getting Data from the Web Moving Work from the Main Thread to an AsyncTask

Posted by Alistair Ruff
Alistair Ruff
3,272 Points

Error: Missing return statement when declaring doInBackground

When declaring doInBackground using the following code:

private class CustomAsyncTask extends AsyncTask<Object, Void, String> {

    @Override
    protected String doInBackground(Object... arg0) {
            String responseString = "";  
    }
    }

which keeps returning this error:

./com/example/MainListActivity.java:20: error: missing return statement
    }
    ^
1 error

I've been tweaking things that make sense in my mind to fix this but with no luck. The line 20 being referred to is the second from last }.

Am I missing something obvious?

2 Answers

Gunjeet Hattar
Gunjeet Hattar
14,483 Points

Hi Alistair,

When you declared CustomAsyncTask you explicitly defined a return type for your method i.e. String. In Android thus Java, when you define a return type for a method, well you have to return the same type of value.

So in your case

private class CustomAsyncTask extends AsyncTask<Object, Void, String> {

    @Override
    protected String doInBackground(Object... arg0) {
            String responseString = "";  

            return someStringValue;  // you will have to return a String value. If you don't you get the error
    }
  }

Hope this helps

Alistair Ruff
Alistair Ruff
3,272 Points
Alistair Ruff
Alistair Ruff
3,272 Points

Thank you, I knew it would be something obvious!