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Android Build a Blog Reader Android App Getting Data from the Web Parsing Data Returned in JSON Format

Posted by Dennis Adriaansen
Dennis Adriaansen
2,299 Points

Working with the loop | Android data from the web

I don't realy understand the loop. Below the code that ive got so far:

String name = jsonData.getString("name"); String publisher = jsonData.getString("publisher"); String language = jsonData.getString("language");

JSONArray jsonBooks = jsonData.getJSONArray("books"); for (int i = 0; <jsonBooks.getJSONObject(i); i++) { Log.i(TAG, "CodeChallange" + title + "," + " " + jsonBooks.length(); }

the error is that > is missing somewhere.

4 Answers

Paul Stevens
Paul Stevens
4,125 Points
Paul Stevens
Paul Stevens
4,125 Points

Hello,

There are a few errors in the code. The error you are getting is because you have missed the i before the < from the second parameter in the for-loop statement.

for (int i = 0; <jsonBooks.getJSONObject(i); i++) {

But that won't fix the problem because the for-loop needs to check the length of the jsonBooks array:

for (int i = 0; i < jsonBooks.length(); i++) {

Then we want to make a variable to store one book at a time inside the for-loop

JSONObject jsonBook = jsonBooks.getJSONObject(i);

Then use that variable to get the details of the book and put into a log message

Log.i("CodeChallenge", jsonBook.getString("title")  + ", " + jsonBook.getString("pages"));

The whole code should be as below:

String name = jsonData.getString("name");
String publisher = jsonData.getString("publisher");
String language = jsonData.getString("language");                                 

JSONArray jsonBooks = jsonData.getJSONArray("books");

for (int i = 0; i < jsonBooks.length(); i++) {
    JSONObject jsonBook = jsonBooks.getJSONObject(i);
    Log.i("CodeChallenge", jsonBook.getString("title")  + ", " + jsonBook.getString("pages"));
}

This was a tricky one, I had to watch the video carefully to get it right. :)

Hope this helps,

Paul :)

william parrish
william parrish
13,774 Points
william parrish
william parrish
13,774 Points

It looks like within your loop, you set the initial value of i by typing "i=0. However after that, you forgot to put the "i" before :

<jsonBooks.getJSONObject.

Dennis Adriaansen
Dennis Adriaansen
2,299 Points

William, you're right thanks a lot for your help!

Dennis Adriaansen
Dennis Adriaansen
2,299 Points
Dennis Adriaansen
Dennis Adriaansen
2,299 Points

Paul,

Thanks for your detailed explanation. I think I understand it now. I appreciate your help.