For loop variable issue

Question

I have developed the following for loop to set the data in a drop down list. This works perfectly if I use a number on the .get() method to select and compare which item has been clicked, but obviously this is useless with a set integer value.

I'm getting the error that the 'a' variable cannot be resolved to a variable.

I'm really not sure why though?

Here's the code:

List<String> list = new ArrayList<String>();
list.add("-");
list.add("Medical");
list.add("Business");
list.add("Family");
list.add("Other");
ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, list);
dataAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
editTime.setAdapter(dataAdapter);

for(int a = 0; a < list.size(); a ++);
{
    // Error on the 'a' variable - cannot be resolved to a variable.    
    if(typeReturned == list.get(a));
    {
        // Error on the 'a' variable - cannot be resolved to a variable.
        editTime.setSelection(a);

    }
}

(or error log - name isn't important :)) – TN888 Jan 29 '13 at 17:43 — TN888, Jan 29 '13 at 17:43
@Ty221, there was no error. – user1352057 Jan 29 '13 at 17:44 — user1352057, Jan 29 '13 at 17:44
@Ty221 Won't compile as-is, hence no stack trace. – Dave Newton Jan 29 '13 at 17:44 — Dave Newton, Jan 29 '13 at 17:44

score 8 · Accepted Answer · edited May 23 '17 at 11:49

You have an unnecessary semicolon after your for loop:

for(int a = 0; a < list.size(); a ++);

If you don't delete it, it is the same as writing:

for(int a = 0; a < list.size(); a ++) { }
// a isn't in scope here any more.

You have the same mistake after your if condition. You have to get rid of that semicolon, too.

Also, I think typeReturned is a String, and you are comparing it with ==. That is a bad idea. You have to use .equals(), if you want to check if both strings have the same content, see:

How do I compare Strings in Java

score 4 · Answer 2 · answered Jan 29 '13 at 17:43

4

Remove the semi colon at the end of your for loop

answered Jan 29 '13 at 17:43

Renjith

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score 4 · Answer 3 · answered Jan 29 '13 at 17:44

4

You have a spare semi-colon at then end of your for loop. Removing that should fix the problem.

answered Jan 29 '13 at 17:44

Tim

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score 4 · Answer 4 · answered Jan 29 '13 at 17:44

4

for(int a = 0; a < list.size(); a ++);

Remove the ; at the end.

answered Jan 29 '13 at 17:44

Grambot

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score 4 · Answer 5 · answered Jan 29 '13 at 17:45

4

You must delete ";" after forand after if.

Your improved code :

    for(int a = 0; a < list.size(); a ++) //WITHOUT SEMICOLON !
    {

    if(typeReturned == list.get(a)) //WITHOUT SEMICOLON !
    {

         editTime.setSelection(a);
    }

    }

Now should be ok.

answered Jan 29 '13 at 17:45

TN888

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1

sorry for my english, i'm not english speaker. i improved this – TN888 Jan 29 '13 at 17:49
1

Your English is significantly better than my Polish ;) – Dave Newton Jan 29 '13 at 18:12

score 3 · Answer 6 · answered Jan 29 '13 at 17:46

3

You have two semicolon after for

for(int a = 0; a < list.size(); a ++);

Also after if

if(typeReturned == list.get(a));

Remove both and it will work

answered Jan 29 '13 at 17:46

Android Killer

18,174
13
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score 2 · Answer 7 · answered Jan 29 '13 at 17:48

Remove the semicolons after if and for statements.

for(int a = 0; a < list.size(); a ++);   
if(typeReturned == list.get(a));

for loop and if statements are not complete statements to put a semicolon after them. They are conditional statements to check for and to execute the block or line after them.

LiaqatG · Answer 8 · 2013-01-30T14:55:01.450

You have just syntax errors in your code as mentioned by others as well.

A semicolon in Java denotes the end of statement so your for loop ends where it encounters the first semicolon regardless of the curly braces afterwards. The rest of the code is considered as a separate block and the variable 'a' is local only the the for loop so is not visible after the first semicolon.

The same applies to the semicolon after the if statement.

for(int a = 0; a < list.size(); a ++);  //** REMOVE THIS SEMICOLON
    {

    // Error on the 'a' variable - cannot be resolved to a variable.    
    if(typeReturned == list.get(a));  //** REMOVE THIS SEMICOLON
    {
        // Error on the 'a' variable - cannot be resolved to a variable.
        editTime.setSelection(a);

    }

    }

Hope this helps.

My friend, this is just a syntax error, nothing wrong with the logic. Yes, you may have a different approach as how to do a specific task to get the same desired result and that will be your 'logic', but having an extra **semicolon, comma, dot,** etc. are part of the syntax of a language. — LiaqatG, Jan 30 '13 at 14:53

score 0 · Answer 9 · answered Mar 21 '13 at 15:08

0

Remove semi colons from if and for statements.

answered Mar 21 '13 at 15:08

NoviceDeveloper

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For loop variable issue

9 Answers9