Wpf binding not updating property

Posted by / 15-Sep-2019 11:15

Wpf binding not updating property

We might first naively define it as such:[code language=”csharp”] string _full Name; public string Full Name [/code]But we would quickly see that this isn’t a wise implementation.

Every time we assign either First or Last name, then we would need to recalculate and reassign the value for Full Name. Clearly, Full Name should be a read-only property – thus eliminating the need to parse anything.

And this is still a rather overly simplistic View Model example – code in the real world is significantly more complicated.

A real app View Model could easily become difficult to maintain if we continue down this path.

For those things we need something with a little more “oomph”.

Building upon the previous example, let’s suppose that we now want to add a “Full Name” property.

If we forget just one, or misspell one, then our View Model will not work correctly.This way, we can unit test our View Models thoroughly, and (sometimes) allow UX designers to dictate the XAML layout directly. As we dig a little more deeply into the mechanisms of data binding, we learn that part of the “magic” is achieved by way of the INotify Property Changed interface (which includes only one thing – an event named Property Changed).Whenever we modify the value of any property on our View Model, we are supposed to raise that Property Changed event, and the XAML runtime will respond by automatically updating the visual state of any controls which are being used to display that property’s data.And that’s why we don’t have the above issue when using ‘classic bindings’, as the binding engine uses reflection at runtime to do the bindings.When using compiled bindings and binding to an interface, make sure that not only the concrete implementation implements the Pieter Nijs aka Pie Eating Ninjas Technical Architect, Senior .

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In the following code im binding Records form a viewmodel , which is using an observablecollection , im also raising the inotifypropertychange, , now i have a button setup which uses the navigation.pushasync method to go to a new page , over there im updating the database Records , i have created a listview in this new page and used the same binding shown here to bind the Records , whenever i add something it updates , but if i press the back button and come back to this Entry Tab Page the binding doesnt update , it only updates if i close the app fully and restart it the data is shown.

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