I'm new to WPF and I wonder if I can use the same approach as I'm using in WinForms.
I want to have a switchable content in a UserControl (like a Wizard) and I want to be able to design all of the pages in this control (in the VS designer, the xaml editor). I want to see the content (every page) in its real container.
I don't want to have every page on a separate UserControl file and I don't want them to share the same space (of the UserControl's client area), which is the case when you're making them all invisible except for the one that is currently displayed (at run-time).
In the WinForms I'm able to switch the page by a button INSIDE the VS form designer. I was even able to create such control myself (with buttons working in design-time). Is there a way to do the same in WPF? I just can't accept the idea that I have to create a new file for every page of the same control...
Thanks!
As stated in the comments above, a TabControl is perfectly suitable for your needs.
The Visual Studio WPF Designer allows you to visualize each TabItem's content at design time:
By simply clicking on the TabItem's header, or focusing their respective XAML tags in the XAML editor:
<TabControl>
<TabItem Header="Tab Item #1"> <!-- Placing the keyboard cursor here will show Tab Item 1-->
<Border Background="Red"/>
</TabItem>
<TabItem Header="Tab Item #2"> <!-- Placing the keyboard cursor here will show Tab Item 2-->
<Border Background="Green"/>
</TabItem>
</TabControl>
If you don't want to show the tab headers, simply customize the TabControl's Template to only show the SelectedContent, like this:
<TabControl>
<TabControl.Template>
<ControlTemplate TargetType="TabControl">
<ContentPresenter Content="{TemplateBinding SelectedContent}"/>
</ControlTemplate>
</TabControl.Template>
<!-- TabItems here -->
</TabControl>
This simple customization preserves the design time preview ability via the keyboard cursor in the XAML editor, while only showing the selected TabItem's content in the UI, with no headers whatsoever.
All this said, and as a side comment, you really need to leave behind the archaic winforms mentality.
First of all, there is no such thing as a "wrong control" in any context in WPF. The WPF Content Model allows for the composition of rich content in almost any situation for almost any parent container, enabling a much greater customizability than archaic technologies.
And no, a TabControl (there is no such thing as a TabPage in WPF) does NOT "only accept TabItems", because, just like any other ItemsControl, the TabControl wraps each of it's items in an Item Container, provided that the item itself is not an item container.
This means that if you place for example, a <Checkbox/> as an item of the TabControl, WPF will automatically wrap the Checkbox with a TabItem. This behavior supports a great range of scenarios and allows for high levels of customizability and complex uses (such as DataBinding and Data Templating) without the need to introduce custom code. In contrast to some archaic technologies such as winforms which literally doesn't support anything except the default horrible stuff and have no support for DataBinding whatsoever.
If you have problems understanding WPF layout, See This Tutorial. Complex, resolution independent layouts are much more easily achieved in WPF (in comparison to useless winforms) due to WPF's pixel independent nature.
Related
I have a string of text that I need to display. I currently display it in a textbox.
My requirements have changed and now I need to display parts of this string in Red.
I have looked and all I can see for displaying text in several colors is a WebBrowser or RichTextbox. Both of these are more complex then I was hoping to use.
I can format the text string in any way (using any kind of markup).
Is there some kind of simple markup control out there for wpf? (Note: This will be going on a datagrid that can have many hundreds of rows, so it cannot be a memory/processing intensive control.)
You can use a TextBlock if it doesn't need to be edited.
From above link:
TextBlock is designed to be lightweight, and is geared specifically at integrating small portions of flow content into a user interface (UI). TextBlock is optimized for single-line display, and provides good performance for displaying up to a few lines of content.
TextBlock is not optimized for scenarios that need to display more than a few lines of content; for such scenarios, a FlowDocument coupled with an appropriate viewing control is a better choice than TextBlock, in terms of performance. After TextBlock, FlowDocumentScrollViewer is the next lightest-weight control for displaying flow content, and simply provides a scrolling content area with minimal UI. FlowDocumentPageViewer is optimized around "page-at-a-time" viewing mode for flow content. Finally, FlowDocumentReader supports the richest set functionality for viewing flow content, but is correspondingly heavier-weight.
Modified example from link showing Red Text:
<Grid>
<TextBlock TextWrapping="Wrap" >
<Bold>TextBlock</Bold> is designed to be <Italic>lightweight</Italic>
and is geared <Run Foreground="Red">specifically</Run> at integrating
<Italic>small</Italic> portions of flow content into a UI.
</TextBlock>
</Grid>
AvalonEdit should do what you want. There is a Nuget package for it. See here also:
http://www.codeproject.com/Articles/42490/Using-AvalonEdit-WPF-Text-Editor
Also, if the text is not being edited, I think you should probably use something like a ListBox with custom item templates -- especially if the entire line is to be highlighted.
(I am trying to learn WPF using tutorials and documentation, and trying to develop a user interface for my backend-complete application while I do say. I've heard people say that the learning curve is quite steep. But sometimes I wonder whether what I'm trying to do is actually something that's hard to do in WPF, or if it's simple but I'm thinking in wrong terms, or if it's neither, it's quite simple but I just happen not to know how.)
Here's my current question. I wanted clicking that clicking some part of my UI will bring up a 'popup' where the user can enter more information. I would like a 'lightbox-style' popup, i.e. the popup is modal to the page, it darkens the rest of the page to become the center of attention, etc. These are seen commonly on Web sites.
A bit of searching led me to the WPF Popup control. I added it, put my content in, set the IsOpen property to True, and -- presto! A popup. Then I added an invisible Rectangle that covers my whole window, and set it to Visible as well when I want my popup to open. Great!
So now I wanted to do this dynamically, because sometimes I will be loading a record which will sometimes have a need to open another control (a UserControl) in a popup to edit its information. So I made myself a method called OpenPopup. But I can't seem to find a way to write this method using WPF. In Windows Forms I'd have written: (I use VB.NET)
Sub ShowPopup (form as Form, ctrl as Control)
'Create 'rect' as new dark rectangle control
'Z-order it to the top
'form.Controls.Add 'rect'
'form.Controls.Add ctrl
'Z-order 'ctrl' to the top
'Center 'ctrl'
'Set focus to it
End Sub
But with WPF I run into problems:
1) I can't add it to the WPF window, because it already has a child.
2) If that child is a Canvas, that's not too bad. I can detect that, and add it to the Canvas. I have to find some way to set its Left, Top etc. properties and Width and Height, since those do not seem to be properties of the Rectangle control but rather extended by the Canvas object -- in XAML they're called Cavnas.Top etc. but Intellisense is not showing them when I try to use it in code.
3) But if it's a StackPanel? Then my rectangle will just be stacked below the other controls! And not covering them! Is there a way around this?
4) And if the window contains only one control and no container control at all?
5) I think there were more problems I ran into. But let's start with these.
Thanks in advance for your help.
1) I can't add it to the WPF window, because it already has a child.
Ah, the evils of codebehind. The solution is not to add it to the visual tree, it is to place it in the visual tree, ready and waiting to pounce, but hide it from the user's view.
Here's a sample you can drop in Kaxaml that demonstrates the point. Set the Lightbox Grid's Visibility to Hidden to access the hidden content.
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Grid>
<Viewbox>
<TextBox Text="SIMULATING CONTENT" />
</Viewbox>
<Grid x:Name="Lightbox" Visibility="Visible">
<Rectangle Fill="Black" Opacity=".5"/>
<Border
Margin="100"
Background="white"
BorderBrush="CornflowerBlue"
BorderThickness="4"
CornerRadius="20">
<Viewbox Margin="25">
<TextBox Text="SIMULATING LIGHTBOX"/>
</Viewbox>
</Border>
</Grid>
</Grid>
</Page>
2) (snip) Intellisense is not showing them when I try to use it in code.
Canvas.Top etal are Attached Properties. Attached Properties are extremely convenient and easy to use in XAML, but they are very confusing and hard to use from code. Another reason why codebehind is evil.
3) But if it's a StackPanel? Then my rectangle will just be stacked below the other controls! And not covering them! Is there a way around this?
I redirect you back to 1. There are also many other container controls in WPF. You should investigate them and observe how they control layout. For instance, my use of the Grid was not to make use of its ability to block off sections of UI for controls, but for its ability to layer controls ontop of each other and to stretch them out to their maximum available size for the available space (the viewboxes are just there to zoom the controls instead of stretch them).
4) And if the window contains only one control and no container control at all?
The root of a window would almost always be a container control. But you control that, so if you needed to add controls to the visual tree at runtime you could easily ensure the child of the window is a container control you could deal with.
5) I think there were more problems I ran into. But let's start with these.
No kidding. My number one suggestion for people in your situation is to drop what you're doing and learn about MVVM. The Model-View-ViewModel is a very simple way to code WPF applications that takes advantage of many of the features of WPF--databinding, templating, commands, etc. It allows you to code your logic not in codebehind (RETCH) but in easy to create and test classes.
As a new comer to WPF, I would like to clarify my approach to build a UI in WPF. I am using WPF with MVVM. My approach is to use a main window which contains user controls which can run several levels deep in the UI tree. For example, I have an editor in a window. Many items can be edited in the editor and the UI for each items are different, but the editor always shows an OK and Cancel button. So the main editor window with OK and Cancel can be shared between several editors. I am designing the app in such a way that the editor user control will just bind the view model for the item which is edited. So when designing the UI for editing individual items OK or Cancel Button is not pulled in, but simply put the item into the main editor which will provide the buttons. I am pretty sure I can handle the commands correctly with WPF command infrastructure.
If I can make it clear with some xaml here it is.Please dont mind the control placement itself, I mean to explain the basic idea of sharing the Common UI across many items.
<UserControl Name="EditorMainWindow">
<Grid>
<StackPanel>
<ItemsControl ItemsSource="{Binding ItemToBeEdited}">
</ItemsControl>
<Button Content="OK" Width="120" Command="{Binding SomethingforOK}" />
<Button Content="Cancel" Width="120" Command="{Binding SomethingforCancel}"/>
</StackPanel>
</Grid>
</UserControl>
The way I am doing it, the user interface tree can go several levels deep. I will be tremendously benefitted, because if the client ask to change the UI in one particular place, I need not got and change it in many places(provided it is shared).
As I am new to WPF I would like to know if there is any catch in this approach. Could you please tell me if this makes sense or not?
You can save yourself a lot of time. Catel already provides such a window:
DataWindow
It is fully ready for MVVM (Catel is also an MVVM framework) which supports dynamic nested user controls. The nice thing is that it also supports error handling out of the box, so as soon as an error occurs in the window template, the user will see the error in the InfoBarMessageControl.
I am building a WPF application using C# 3.5
I have a WPF menu on the top of the application.
When clicking on a top level menu item, i need the second level of the menu to show horizontally instead of vertically "and" remain opened ( not disappear like a normal menu).
What I need to have is something similar to the following screen shot
alt text http://img341.imageshack.us/img341/1694/navigationecopy.jpg
How can I style the WPF menu to change its behavior as above?
Ok after trying this out, I don't think re-templating the Menu is a good idea. Menu is a very complex control. A better idea would be to avoid using a menu entirely and use a control with behavior similar to what you've described (selected items remain open, can display their children horizontally, etc.). The TabControl is a very good fit so I would simply use that instead. Here is some sample XAML to show you how this could work:
<TabControl VerticalAlignment="Top">
<TabItem Header="MAIN ACTIONS"/>
<TabItem Header="GOALS" IsSelected="True">
<StackPanel Orientation="Horizontal">
<ToggleButton Margin="5">Enter Goals</ToggleButton>
<ToggleButton Margin="5">Edit Goals</ToggleButton>
<ToggleButton IsChecked="True" Margin="5">View Work Plan</ToggleButton>
</StackPanel>
</TabItem>
<TabItem Header="ACTIVITIES"/>
</TabControl>
Obviously, you will need to restyle the TabControl with fonts and colors to get the appearance you want. And for the submenus, I would actually use radio-buttons instead of toggle buttons, to ensure that only one can be selected at a time (you will need to re-template the radio-button as well). But looking at even this simple result, you can see that this control is quite well suited for your scenario:
alt text http://img94.imageshack.us/img94/2358/tabcontrolmenu.png
I am new to WPF and I have a doubt in modifying a control. I came to know that one can modify a control by changing its Control Template. i.e.,
<Button>
<Button.Template>
<ControlTemplate>
...
</ControlTemplate>
</Button.Template>
</Button>
Also we can edit a control utilizing the Content Model. i.e.,
<Button>
<Grid>
<CheckBox>
</CheckBox>
<RadioButton>
</RadioButton>
...
</Grid>
</Button>
What is the difference between these two techniques. Which one is the correct way to customize a control in WPF. Please help me in understanding this better.
The primary difference between these two things, is that the ControlTemplate defines the look of the control. It is not actually placing content inside of it. At some location inside the content control, there should be some form of ContentPresenter. The built in controls are capable of this because they are what is known as 'lookless controls', and any custom controls created should also be lookless. When a control is not templated in a lookless manner but instead has a static layout, then the confusion you have run into can occur.
As for the correct way to do things, it depends on what you are trying to achieve. If you are attempting to change the control, such as the look and feel or the behavior, then using a ControlTemplate, (or DataTemplate, depending on what you are templating), is definitely the way to go. A good example of this is the CheckBox, belive it or not, the CheckBox is actually a ToggleButton (more or less), that through templating displays the togleablity in a bullet. Here's another very good example of how you can use Templates to do some very nifty things.
ControlTemplates should also be applied through Styles, instead of directly set on an element.
If you aren't actually aiming to modify the behavior or look of the control then using the content model is the correct approach.
WPF does this better then Silverlight, though I don't know if there are improvements in SL3.
My rule of thumb is that if it's possible to get what I want without changing the control template then you shouldn't change the control template.
control templates are a way to change the look&feel of a control, for example making a round button of changing the check mark graphics of a checkbox.
adding controls inside a control is simpler, for example place an image inside a button.
Also remember, there is a lot of functionality in the control template, including padding, content alignment, disabled look and more, if you change the control template you will have to add support for all of those features.
Template can be placed into a resource and re-used for another button.
Changing content directly is not re-usable unless you make a UserControl out of it.
Which one you use depends on a concrete task and your personal preferences.