设置动态创建的控件的数据上下文

Question

I have a UserControl (Map) that contains a Canvas control. I am dynamically adding a control (Gate) to this canvas from the code behind.

I want the Gate objects DataContext to be the "Gate" property of the Map's DataContext. This is being done in the code behind.

 Binding dataContextBinding = new Binding();
        dataContextBinding.RelativeSource = new RelativeSource(RelativeSourceMode.Self);
        dataContextBinding.Path = new PropertyPath("DataContext.SelectedLevelModule.Gate");
        dataContextBinding.Mode = BindingMode.TwoWay;
        dataContextBinding.UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged;
        BindingOperations.SetBinding(gate, DataContextProperty, dataContextBinding);

After this block of code runs, the gate.DateContext is null... Any ways this can be done? Drawing a blank.. Thanks Harold

Answer 1

You are setting the property path to DataContext.SelectedLevelModule.Gate . You are then assigning the binding to the DataContextProperty . I think what is happening is that the path is now gate.DataContext.DataContext.SelectedLevelModule.Gate .

Try removing DataContext from your PropertyPath and see if that fixes it. You are already assigning it to the DataContext, you should not have to specify it in the Path.

var dataContextBinding = new Binding();
dataContextBinding.Path = new PropertyPath("SelectedLevelModule.Gate");
BindingOperations.SetBinding(gate, DataContextProperty, dataContextBinding);