1. The table of the Program of training
2. The table courses
3. Questionnaires ( Of this table is construction CHART)
I want to construct Cascading ComboBox in which selecting programs of training and then courses. After a selection of course, making data from table Questionnaires and construction Chart
How to connect Chart at the first start of page when still it is not known on what identifier to select the data from the table
See my code.
How it to make?