![]() ![]() When it's detached from the view, the same method is called with null parameter to clear the association. When view model is attached to the view, its SetPasswordBox method is called with PasswordBox as a parameter. This code assumes that the PasswordBox control is named in XAML: (model, box) => model.SetPasswordBox(box)) This is all wrapped in a helper class, so all I have to do in the UserControl is to modify the constructor slightly: public LoginWindow( ) So I monitor the DataContext and upload the offending controls or their properties to whatever view model gets linked to the UserControl. I follow the convention that DataContext of UserControl is set to its view model. I am dismissing bindable wrapper controlsįor the same reason of being control-specific. I tried to create general-purpose solution via attached property,īut it failed in fringe cases due to some mysteries deep in WPF implementation. I am however looking for something more general-purpose. (with many variations circulating around the net) that makes the Password property bindable. PasswordBox in particular already has a specialized solution via attached property ![]() This solution unfortunately breaks down rather quickly once you start doing anything non-trivial, for example trying to set initial value for the PasswordBox. One can even insert a converter in the command parameter binding to wrap the PasswordBox in an interface to comply with MVVM. ![]() We are really looking for some way to have the control in both view and view model.Īnother simple solution, especially popular with PasswordBox, is to ship the control to view model as command parameter, e.g. Aside from being totally non-MVVM, this technique has the downside of forcing all properties and children of the binded control to be set from within view model. One can just instantiate the offending control in view model and then bind it down to the view via ContentControl. I have another simple technique that can be used anywhere in XAML code. It relies on user controls, which are a serious performance killer in WPF. There are many viable workarounds, which I will discuss briefly before presenting my favorite one liner. That's bad design, of course, but these controls are a given and all we can do is to invent clever workarounds. These controls essentially blend data representation and UI in one class. PasswordBox or the 3rd party Awesomium WebControl. There are some controls in WPF that aren't designed for proper binding from view models, e.g. Reason: JungleControls library is no longer maintained. Information presented on this page might be out of date. Robert Važan Expose WPF controls to view models IIĪccess controls from within view model by adding a bit of code into window constructor. ![]()
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