Wpf listbox selecteditem not updating

There are two different scenarios that you may or may not want to handle when dealing with data source changes: Changes to the list of items and changes in the bound properties in each of the data objects.How to handle them may vary, depending on what you're doing and what you're looking to accomplish, but WPF comes with two very easy solutions that you can use: The Observable Collection and the INotify Property Changed interface.The following example will show you why we need these two things: Try running it for yourself and watch how even though you add something to the list or change the name of one of the users, nothing in the UI is updated.

wpf listbox selecteditem not updating-85

Wpf listbox selecteditem not updating bigchurch christian dating service plus

This will make the Add and Delete button work, but it won't do anything for the "Change name" button, because the change will happen on the bound data object itself and not the source list - the second step will handle that scenario though.

The second step is to let our custom User class implement the INotify Property Changed interface.

With the two changes described above, we now have an example that WILL reflect changes in the data source.

It looks like this: As you can see, implementing INotify Property Changed is pretty easy, but it does create a bit of extra code on your classes, and adds a bit of extra logic to your properties.

The Items Source of the list is assigned to a quick list of a couple of users that we create in the window constructor.

The problem is that none of the buttons seems to work. The first step is to get the UI to respond to changes in the list source (Items Source), like when we add or delete a user.The Name property represents the name of the control, which is a unique identifier of a control.The Margin property tells the location of a List Box on the parent control.By doing that, our User objects are capable of alerting the UI layer of changes to its properties.This is a bit more cumbersome than just changing the list type, like we did above, but it's still one of the simplest way to accomplish these automatic updates.The problem is simple: By default WPF compares Selected Item to each item in the Items Source by reference, meaning that unless the Selected Item points to the same item in memory as the Items Source item, it will decide that the item doesn’t exist in the Items Source and so no item gets selected.

Tags: , ,