This question already has answers here:
What is the difference between a User Control Library and a Custom Control Library?
(3 answers)
Closed 1 year ago.
I'm working on creating a date/time user control in WPF using C# 2008. My first user control. I'm also using Matthew MacDonald's book, "Pro WPF in C# 2008". In that book he strongly recommended creating a user control using the WPF Custom Control Library project template; so I followed his suggestion. I've finished writing the code which would go into what I think of as the code-behind file. Now I'm ready to write the XAML.
The only problem is, I just discovered there is no corresponding .xaml file? So, I don't get why using a WPF Custom Control Library project is better, or prefered, when writing a user control?
A user control and a custom control solve two distinctly different problems.
UserControls are meant to compose multiple WPF controls together, in order to make a set of functionality built out of other controls. This is often used to compose a portion of a window or screen in order to organize your development by allowing you to group multiple pieces of functionality into one "control". For example, if you wanted to make a control for editing a User which provided text boxes for first and last name, age, etc., a single UserControl could be dropped onto a Window and bound to a User instance to edit this. (In this case, you're using standard controls, such as TextBox, to "compose" a control for a more complex purpose.)
A CustomControl, however, is meant to be a new single control. This would typically be a replacement for a built-in control (which could not be redone via templating). I've found that the need for CustomControls is actually fairly rare in WPF, since the WPF templating options and attached properties allow you to do nearly anything with standard controls, once you learn them fully.
I would also add, if you're intending to inherit from your control, then using a usercontrol is will complicate matters. For example, if create a base usercontrol that has a layout defined in Xaml, WPF framework won't allow you to inherit this control and use Xaml to define the layout for the subclass. In dotnet 3.5 Xaml control can't inherit from another Xaml control
Related
I've created a groupbox that is used to populate a list of files and their description. I've also written the code behind for properly adding the files. Is it possible to share the code behind and UI so that it can be used in other forms without having to rewrite the code? I know that you can create a base form, that contains the winforms control you want to share. That way you can have your new form you inherit from the base class. But I'm not looking to implement it this way.
YES, it can be. Create a User Control for your GroupBox and use the same in whichever form you want. User controls are meant for that purpose to increase code re-usability.
In case, you think the same GroupBox control can be used in other project as well then you should consider building it as Custom Control
ı have been serching this for a while but I couldn't come up with a conclusion. What is UserControl? For me we can do everything with creating new windows forms instead of User Control. I know there is a reason to use but it is not clear right now. If someone illuminates the mystery that would be great.
A user control is basically a grouping of other existing control, intended as a reusable component (i.e. composite control). If you need to place the same group of controls on different windows you'd rather group them in a user control, adding things like data validation for instance, and then reuse this control whenever you need it.
Here is some more reading.
UserControls allow you to reuse your code. For example if you need a small component that displays two values (code and description), with UserControls you can design it only one time and then reuse it in other forms.
Also, you can add your custom properties\methods to the UserControl; in this way you can define simple (or even more complex) functions associated to the GUI control.
Hope this helps.
imagine you have a GridView with some new methods you create, and which you want to use on several pages. There you go. A UserControl is useful. That's just one example
As the others have explained a UserControl groups 'real' Controls and the logic that makes them work together as one component.
Imagine an application where the user can decide wether it runs in MDI mode or with separate windows or with tabbed pages. You can add the UCs of your application to any of these easily.
Think of a MP3 player with various controls, buttons, labels and sliders and user drawn-gauges. If it's in a UC you can re-use it directly. If it is all on a window, how do you re-use it?
So UCs are about flexibilty and re-using visual components.
I've a question more about 'Good Programming Practices'.
I have just started a really big project. I'm using WebGui (long story short.. it is WinForms in web) - but it's not important.
I'm creating milions of forms with milions of controls like TextBox, NumericUpDown, DateTimePicker and etc. It might happen, that I will have to change something in behavior of DateTimePicker or appearance. It will be impossible to change it in every control. I want my project to be flexible so I've got an idea..
I do separate custom controls for every type - string, numeric, date, byte.. and within I will put TextBox for example. And on every form I will put not TextBox, but MyTextBox. In fact, that MyTextBox will be just TextBox, but when I change something there, every control will be changed.
Is it good, popular pracitce in programming?
in the case of WPF this can be achieved quite easily using Styles and Templates.
in Winforms this is not possible, therefore I'd say your approach of deriving from the controls and using your own custom controls on the UI is a good practical approach which helps managing changes centrally.
If the controls were created manually in the programme, alternatively you could use a Factory clase(s) and get the Factories to create the controller object rather than just newing up.
But this might not be possible when the UI is created by dragging and dropping controls as the developer has no control over the creation of controls.
Which ever the approach you choose, the fundamental goal should be to centralize the creation logic of the controlls.
Yes, this is perfectly normal programming practice for GUI development, if the standard controls don't satisfy your requirements.
Most developers get 3rd party control suites for the extra flexibility. The benefits in buying far out weigh the benefits in building core controls yourself.
I've worked at a place that did companyTextBox, companyDatePicker and it worked ok. A couple of controls got revamped over .Net versions so these base classed controls required some surgery. Any depreciated controls were left as framework version dependent.
For special things, I do a lot of research into good custom controls on CodeProject, CodePlex, Code.Google.com,etc and implement them into the project I'm working on.
Otherwise use the stock standard controls or the suite of 3rd party controls the company I'm working for use.
My advice is to get a 3rd party suite of controls and make a ton of re-usable user controls based on the 3rd party ones. This way you can build most of the 200 forms by Drag and Dropping the user controls onto the forms. Make each User-Control Implement an Interface with Create,Retrieve,Update & Delete methods for the forms to generically work with your user controls.
I have been trying to customize a webbrowser control in wp7. All I need to do is to add a border property(I think it is already available in webbrowser but I have to make it mandatory when I make it as a control) and want to add a few extra event handlers and make it as a control so that it can be used later in different projects.
I tried reading through materials in msdn for writing control template and it all revolves around writing a few xaml code and attaching it with codebehind to make it work. What I don't understand is how do I learn xaml? or in other words where is the reference for all the tags that msdn talks about in xaml? Itseems to be huge and I am not sure how to go about it. The tutorial in msdn straight away divulges into xaml code and I am totally confused..
So now all I am trying to do is this,
create a control in Expression Blend (Windows Phone Control Library) that would create a class (MyCustomControl) that inherits
from CustomControl base class.
Now in xaml I am adding a webbrowser control and adding four event handlers (mouseup,down etc.,).
I build this control in blend and add the corresponding dll in VS2010.
And now once I try to add this control to my wp7 phone application it says "Cannot create an instance of MyCustomControl"..
These were further links that I referenced in creating one,
Windowsphone - Creating a custom control
Windowsphone - Control Template.
UserControl vs Custom Control
Creating a new control by creating ControlTemplate
Any further help would be great.
There is no definitive list of 'elements' you can add to your XAML. The reason for this is that the XAML parser can create any class which is a UIElement based on the XML you provide. So the elements available to you depend on the assemblies present in your project. Read teh MSDN XAML Overview for details
For a list of controls that are present by default, take a look at the System.Windows.Controls namespace (I think this link is not for your version of Silverlight, it might be best to use the Object Browser to look at the assemblies in your project).
For your problem, where you want to add a border to a WebBrowser control. I would recommend creating a UserControl as per this tutorial.
I created a TabControl using Windows Forms but the tab headers look very ugly. I want to make them with rounded corners and also create some space between two tab headers. Can anyone please tell how it can be done using C#.
Thanks,
gary
You'll want to do one of a few things:
Make your own custom control that inherits from TabControl and overrides its render method.
Download a third-party custom tab control that does what you want.
Switch to WPF, which gives you some more flexibility in the way of creating and styling controls.
There isn't a way to do this with System.Windows.Forms.TabControl out of the box, so you'll have to either live with what you've got, or roll your own.
Not to spark any heated debate, but WinForms is an aging API. If you're building a brand new application and/or learning a UI framework for the first time, you might consider using WPF instead. For legacy code, it's fine to maintain WinForms of course.
The System.Windows.Forms.TabControl class is just a wrapper around the Windows COMCTL32 tab control. Unfortunately, that control doesn't provide much in the way of customization options. You'll have to switch controls, either to WPF, custom code, or some third-party product.