![]() ![]() However, sometimes, you just want to have a quick solution. This route does work very well for quite a few scenarios. Now, one solution to that very problem are ViewModel wrapper classes that optimize the business logic for your specific UI logic. From the control’s point of view, this means that the "Folder" nodes and the "Farmer" node are siblings. Note the difference: We want to organize the Animals and Crops collections within individual sub folders, while the "Farmer" node is a direct child of the "Farm" root node. Image your Farm class looks like this:Īccordingly, you might want to display that information according to the sketch below: However, more often than not, you’re running into more complex scenarios where additional structuring is necessary. It does not store any personal data.Most WPF TreeView samples you see on the web are somewhat simplistic: While they may provide heterogeneous data, usually all childs of a given node are of the same type: The cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. The cookie is used to store the user consent for the cookies in the category "Performance". This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other. The cookies is used to store the user consent for the cookies in the category "Necessary". The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional". The cookie is used to store the user consent for the cookies in the category "Analytics". These cookies ensure basic functionalities and security features of the website, anonymously. Necessary cookies are absolutely essential for the website to function properly. ![]() I suggest you download my source example that does not include the above and then try to add what I discussed here. During the binding of the treeview to the window, the convert method is called and the image is swapped for the header. The above calls accesses the HeaderToImageConverter class via the static variable named Instance. The final step is to add the XAML code to the window. The Convert method simply checks if the class being passed to the method is of type TreeViewModel, casts it and then checks the IsRoot Boolean value. Throw new NotSupportedException("Cannot convert back") Public object ConvertBack(object value, Type targetType, Uri uri = new Uri("pack://application:,/blue.png") New Uri("pack://application:,/green.png") īitmapImage source = new BitmapImage(uri) TreeViewModel tvm = (TreeViewModel)value Public object Convert(object value, Type targetType, ![]() Public static HeaderToImageConverter Instance = Public class HeaderToImageConverter : IValueConverter This class needs to implement the IValueConverter which requires that we implement a Convert and ConvertBack method. The next step is to create a new class that converts the treeview header into an image. The final thing I did in my treeview model class was to set the IsRoot value to true where a treeview item had children. I also modified the constructor by defaulting the IsRoot property to false. This is because I can’t think of a reason this value should be changed after the creation of the treeview has been completed. therefore I made the property public but made the setter private. I was it to be readable from everywhere, but I only want it set from within the class. Let’s modify the treeview model first by adding a Boolean to the properties called IsRoot. Using my previous example of a treeview class, let make a few quick changes to add some images. It was hard to find the solution than it was to implement the solution. In this solution I will use a ValueConveter to convert a treeview header to an image. The term I was looking for, while trying to find a solution was ValueConverter. I had this again while trying to add images to a treeview. Like I’ve said before, once you find what your looking for, it is easy to find examples about how to use and implement it.
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