Hi @caligame ,
The previous solution I gave you is fine. But, to make sure you don't see any possible circular reference error, please consider using the following. Below I provided the complete solution for all comboboxes. Just make sure you replace the datasource and the column names (car, Type and color) with the exact names as per your datasource. You don't have to change varCombo1, varCombo2, varCombo3. These are just variable names used to help avoid circular reference errors.
On the items property of combo 1:
Filter(YourDataSource,(Type=varCombo2 Or IsBlank(varCombo2)) && (color=varCombo3 Or IsBlank(varCombo3) ))
On the items property of combo 2:
Filter(YourDataSource,(car=varCombo1 Or IsBlank(varCombo1)) && (color=varCombo3 Or IsBlank(varCombo3)) )
On the items property of combo 3:
Filter(YourDataSource,(Type=varCombo2 Or IsBlank(varCombo2)) && (car=varCombo1 Or IsBlank(varCombo1) ))
On the OnChange property of combo 1:
If(!IsBlank(Self.Selected), UpdateContext({varCombo1:Self.Selected.car}), UpdateContext({varCombo1:Blank()}))
On the OnChange property of combo 2:
If(!IsBlank(Self.Selected), UpdateContext({varCombo2:Self.Selected.Type}), UpdateContext({varCombo2:Blank()}))
On the OnChange property of combo 3:
If(!IsBlank(Self.Selected), UpdateContext({varCombo3:Self.Selected.color}), UpdateContext({varCombo3:Blank()}))
