Extension. Prevent multiple response from GetQvObject method

Sergey_Shuklin — Sun, 08 Jul 2018 14:16:37 GMT

Hello, Everyone!

This material will show how to avoid strange issue of qva.GetQvObject method.

The issue is response from this method's callback is repeated multiple times.

Honestly I don't know why it's happening, but I know how to struggle with it.

Let's take a look at simple instance. We have an extension that should create a rabbit each time we press the button "Rabbit!".

After three hits we want to get something like this:

We use qva.GetQvObject method for getting a value from TextBox text with "var_tb" ID:

If we don't use special preventing condition our result after three hits will be:

This is definitely not what we want. After few more clicks we will have a plenty of rabbits.

All you need to do is to add an extra IF-condition which will prevent of using callback function if true:

That's all. "stop_multi" will be increased each time method is passed so when we get value of it greater that zero callback will be prevented.

Hope it will help you with improved development 😃

article Extension. Prevent multiple response from GetQvObject method in Qlik Learning Documents