I have a property of type List<MyItems> with the DesignerSerializationVisibility(DesignerSerializationVisibility.Content) attribute in MyCustomControl class. This allows the collection to be properly serialized to the designer file.
How do I initialize this collection such as when the user drags MyCustomControl on the Form, 3 items are added automatically? Exactly how the standard TabControl does with TabPages.
I guess that a method like the ASP.NET CreateChildControls() should exist for WinForms to accomplish this.
Thanks.
I discovered you need to implement your own designer and override the InitializeNewComponent() method to create child controls and eventually the InitializeExistingComponent() to edit them.
Related
Windows Phone 8 project, XAML. I have a ListBox inside a pivot item that's of my own class MyPivotItem (derived from vanilla PivotItem) inside a page. The listbox has an ItemTemplate with some controls. I'd like to bind an event in one of those controls to a method in MyPivotItem. The plain syntax Click="OnClick" does not work - the frameword searches for the method in the Page class only.
I could derive the control itself and do some trickery with tree navigation and event forwarding and so on, but I wonder if such a scenario can be served by XAML's internal means.
Is there any way to bind methods non-programmatically to a class that's deeper in the hierarchy than the root object of the XAML file?
Without using something like behaviors or attached properties, it is not possible. XAML file is always associated with partial C# class and in this class you define your controls and events. For every Page.xaml, a Page.g.xaml file is generated that actually creates controls and binds events. However, those events must be defined in root object - the partial class itself.
Even if you create a workaround using either attached properties or behaviors, you are simply offloading that programmatic code to some other place and hiding it behind XAML syntax.
When would you want to bind to control's specific event handlers anyway? Can you simply use UserControls for that?
I would like to create a Silverlight custom control using C# only, without any xaml.
Here is my work so far (stripped down to the bare minimum for the question):
I tried to inherit User control as follows:
public class myControl: UserControl
{
// class code
}
And adding it to the LayoutRoot:
myControl control = new myControl();
LayoutRoot.Children.Add(control);
The control is added, but its invisible!!
How can i make it visible ? Is there something i missed ?
edit: The only visual element in my contorl is a grid with an image background
Your Usercontrol will be empty and have no visual effect until you give it a child control via it's Content property.
Well unless you put a template in place or add elements in code, UserControl is empty.
Maybe you could try inheriting from an existing control which has a template, like Button, etc and change that in code?
I have a object that inherits from TabItem. I have a bunch of Database objects that will reuse the same code so I wanted only one TabItem class and then use DataTemplates to control how each object gets presented.
Problem is that the TabItem shows a collection of Objects and ObservableCollection is concrete.
I've pondered a few solutions but none of them work. Seems like I will have to create one class for each object type even when they will all be the same (except for ObservableCollection having different types). That's not very DRY.
I can't make a UserControl generic, I can't let the UserControl constructor take in a generic class ( unless I define the Type wihc I don't wan't to do). I guess creating a base UserControl class and then inheriting that will have to do. Does it inherit the XAML code as well or will I have to rely on styles and templates?
Am I missing something?
Look into using DataTemplateSelector to provide flexibily in how you present your data in WPF.
Here are three sites that helped me:
Data Templating Overview
How to use DataTemplateSelector to alter views of objects in a ListBox
WPF Tutorial - How To Use A DataTemplateSelector
I have a WPF user control ...which is in MVVM. The user control(which contains a listview) need data from the page (where it is included). I have to set a property to get this data input. Will this comply with MVVM...if not, what is the way for the same?
I'm afraid this won't be correct in MVVM design pattern. try to stick to your view model to define properties. Why don't you consider moving that property to control's vm?
Use an ObservableCollection rather.
ObservableCollection<myModel> myOC = new ObservableCollection<myModel>();
where myModel is a class that has to be constructed transforming your columns in the DataTable to Properties.
In your MainViewModel, loop through the DataReader and create myOC out of it.
Now bind myOC to a ListView in your page.
The DataTemplate of ListView should be a view(UserControl) drawing data from a ViewModel constructed out of myModel
But your UserControl has the entire ListView inside. If that is on purpose, then let me know the entire design to give a better idea.
I have legacy windows forms user control that exposses several public methods. I wrapped this control on a wpf user control and encapsulated the Methods with a relaycommand on the new wpf usercontrol.
Now my problem is how to use the mvvm pattern to execute the commands on my user control form the viewmodel that is used with the view hosting the new wpf usercontrol.
In viewmodel you have to add a field say
Public ICommand CommandOne
Now this command will create a new RelayCommand object depending upon your requirements/conditions.
Now, you can bind this 'CommandOne' command with any object say button on your control form.
So, whenever the button is clicked then the RelayCommand object will be created and it will execute the action given to it as a parameter.
Hope it works for you.
I Fond out how to get this to work with bindings. Need to set the mode to OneWayToSource to get the command from the user control. The tricky part is that the initialization of the command has to be done inside the loaded event of the usercontrol. If you try to do it inside of the constructor, you will end up with the default initialization from the binding which could be null.
Use PRISM EventAggregator? You can fireoff an event from ViewModel, from your Usercontrol subscribe to it.
http://www.codeproject.com/Articles/355473/Prism-EventAggregator-Sample
https://msdn.microsoft.com/en-us/library/ff921122.aspx