Start Dependency property not updating ui

Dependency property not updating ui

The main difference is, that the value of a normal .

Obviously we can put code into the setter of the property … WPF will sometimes update the values directly without calling our object code) this will not cover all eventualities. Event handlers are typically removed as part of the Dispose pattern, and then everyone tries really hard to make sure views and other objects get disposed properly.

And so the WPF team came up with a way of notifying our code when a value changes – the Dependency Property Descriptor.

When you set a value of a dependency property it is not stored in a field of your object, but in a dictionary of keys and values provided by the base class Every time you access a dependency property, it internally resolves the value by following the precedence from high to low. The key of an entry is the key defined with the dependency property. NET property wrapper, it internally calls to access the value.

It checks if a local value is available, if not if a custom style trigger is active,... This method resolves the value by using a value resolution strategy that is explained in detail below.

Your attributes should not be what depends on you but what you depend on.

The issue is that if I create a derived class and it has properties that depend on a base class property, the base class property would not know to add the dependency.

They allow you to attach a value to an object that does not know anything about this value. Each layout panel needs different data to align its child elements. Since you can write your own layout panel, the list is infinite.

So you see, it's not possible to have all those properties on all WPF controls. They are defined by the control that needs the data from another control in a specific context.

Wrapper method is defined as 'int' but Dependency Property is already as 'bool'. Thank's again :) Hi Christian Thanks for your detailed explanation! At the begining when you expalnied about the advantages one of them was " Reduced memory footprint" u wrote that when using DP it reduces memory storage compare to Normal Properties because it "only stores modified properties in the instance & The default values are stored once within the dependency property".

Also, i couldn't use 'Listen to dependency property changes' section. I understand that when storring only changes it reduces memory storage but what does it mean that the default values are "stored within the dependency property"? You wrote that DP are stored in Dictionary instaed of Field like Normal properties. I understood that there are " Readonly DP" but i have noticed that when using the shortcutin Visual Studio for creating regular DP (propdp) a " public static readonly Dependency Property My Property" is added. At the begining when you expalnied about the advantages one of them was " Reduced memory footprint" u wrote that when using DP it reduces memory storage compare to Normal Properties because it "only stores modified properties in the instance & The default values are stored once within the dependency property". why when updating data from Model to View we have to use DP or Notifty Property Change instead of normal property, and when updating data from View to Model we have to use Normal Property?

To create a Dependency Property, add a static field of type to create an instance of a dependency property. If you set the property from XAML the Set Value() method is called directly.