For/While loop struggles with async calls

Question

am trying to check element on regular interval and click only if it is present. Some times this element appears in 2-3 minutes. If it is not present, i want to wait for few seconds and then refresh page

Here is what i tried:

for(var i = 1; i < 60; i++){
    element(that.proposalByOrderPath(num)).isPresent().then(function(result){
        if(result){
            console.log(i);
            return element(that.proposalByOrderPath(num)).click();
        }
        else{
            browser.sleep(15000);
            browser.refresh();
       }
    });
}

As an output, it prints 60 twice. It clicks on the element once but tries to look again for the element and throws "element not visible" error.

Maybe you need to set the element's `visible` field to `true` before clicking on it? — stanm, May 18 '15 at 15:36
main issue is loop gets done before it goes to check element — Gyanendra Mishra, May 18 '15 at 16:03

score 0 · Answer 1 · edited May 23 '17 at 10:27

0

This is a closure issue. For more understanding read the following-

How do JavaScript closures work?

http://www.w3schools.com/js/js_function_closures.asp

edited May 23 '17 at 10:27

Community

1
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answered May 19 '15 at 11:36

Rahul Vig

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score 0 · Answer 2 · answered Jul 31 '15 at 08:26

We can solve async call in for loop with any of following 3 ways:

Callback

var a = function(callback){ //code
callback(); }

var b = function(){ for(loop details){ that.a(function(){ }) } }
By recursive call of function instead of using for loop
By self iteration

for(loop details){ (function(i){ //your code })(i); }

For/While loop struggles with async calls

2 Answers2