Your mistake is that you called a count method. According to the name, it takes the quantity, but your question asked about summation. I don’t know what you want to do specifically. However, since ProductCategoryDataModel is customized by you, if its parent class does not have a count or sum method, you need to implement the corresponding method yourself before you can call it.
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Your mistake is that you called a count method. According to the name, it takes the quantity, but your question asked about summation. I don’t know what you want to do specifically. However, since ProductCategoryDataModel is customized by you, if its parent class does not have a count or sum method, you need to implement the corresponding method yourself before you can call it.
If you are counting the number of dictionaries,
somedict.allKeys.count
or
somedict.allValues.count
What class does
model inherit from?
In addition, you can implement the
-count;method by yourself