The ScrollViewer class in C and.
To implement scrolling functionality on a content control, the content control is placed as the default content of a ScrollViewer control using its Content property. A ScrollViewer can only have one child, typically a Panel element that can host a Children collection of elements.
The simplest way to enable scrolling on a content control is by placing the content control inside a ScrollViewer control. The following code snippet places a StackPanel control within a ScorllViewer control. The StackPanel is placed within a ScrollViewer. The scrolling is enabled by default and both horizontal and vertical scrollbars are visible because the content Rectangle is larger than the parent control, StackPanel.
You can resize the Window and you will see the ScrollViewer appears and disappears when the Windows is smaller and larger than the content, respectively. The ScrollViewer control responds to both mouse and keyboard commands and defines numerous methods with which to scroll content by predetermined increments. You can use the ScrollChanged event to detect a change in a ScrollViewer state. It has four values - Auto, Disabled, Hidden, and Visible that are self-explanatory.
In most cases, you may want to keep the default Auto property that shows or hides scroll bars as needed. The following code snippet sets both, vertical and horizontal scrollbars to Auto.
You can disable and hide scrollbars by setting these values to Disabled and Hidden respectively. The Visible value makes sure the scrollbars are visible all the time regardless of the content needed scrolling or not.
Then place a TextBlock control and few more child controls as a part of the content. The following code snippet enables horizontal and vertical scrollbars in a TextBox control.
The ScrollViewer needs to apply to the root container control. The following code snippet adds scrolling to a StackPanel. View All. Mahesh Chand Updated date, Dec 15 The simplest way to add scrolling functionality to a TextBox control is by enabling its horizontal and vertical scrolling.
You can use a ScrollViewer control to enable scrollbar on a Window. Next Recommended Article. Getting Started With. NET 5.Content within a user interface is often larger than a computer screen's display area. This topic introduces the ScrollViewer element and provides several usage examples. The ScrollViewer control encapsulates horizontal and vertical ScrollBar elements and a content container such as a Panel element in order to display other visible elements in a scrollable area.
You must build a custom object in order to use the ScrollBar element for content scrolling. However, you can use the ScrollViewer element by itself because it is a composite control that encapsulates ScrollBar functionality.
The ScrollViewer control responds to both mouse and keyboard commands, and defines numerous methods with which to scroll content by predetermined increments. You can use the ScrollChanged event to detect a change in a ScrollViewer state. A ScrollViewer can only have one child, typically a Panel element that can host a Children collection of elements.
The Content property defines the sole child of the ScrollViewer. Physical scrolling is used to scroll content by a predetermined physical increment, typically by a value that is declared in pixels. Logical scrolling is used to scroll to the next item in the logical tree.
Physical scrolling is the default scroll behavior for most Panel elements. WPF supports both types of scrolling. The IScrollInfo interface represents the main scrolling region within a ScrollViewer or derived control. The interface defines scrolling properties and methods that can be implemented by Panel elements that require scrolling by logical unit, rather than by a physical increment.
Casting an instance of IScrollInfo to a derived Panel and then using its scrolling methods provides a useful way to scroll to the next logical unit in a child collection, rather than by pixel increment.
By default, the ScrollViewer control supports scrolling by physical units. For layout controls that natively support logical scrolling, you can still achieve physical scrolling by wrapping the host Panel element in a ScrollViewer and setting the CanContentScroll property to false.
The following code example demonstrates how to cast an instance of IScrollInfo to a StackPanel and use content scrolling methods LineUp and LineDown defined by the interface.
The following example creates a ScrollViewer in a window that contains some text and a rectangle. ScrollBar elements appear only when they are necessary. Like all controls in Windows Presentation Foundation, the ScrollViewer can be styled in order to change the default rendering behavior of the control.If you are programming applications which should be used on a touch screen then you may have encountered the problem that it is tricky to use the scrollbar with the finger.
Because the default scrollbar is to small. If you want to adjust the width of all scrollbars in your application you can put this piece of code into you resources.
Your solution will work for a vertical scrollbar but will not display the horizontal scrollbar correctly. Here is some XAML that works a bit better.Why WPF and compare WPF with Winforms ? (WPF Interview question with answers)
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Notify me of new posts via email. Enter your email address to subscribe to this blog and receive notifications of new posts by email. Sign me up! Share this: Twitter Facebook. Like this: Like Loading Kulvir Kaila kulvirkaila August 15th, TrackBack URL. Leave a Reply Cancel reply Enter your comment here Fill in your details below or click an icon to log in:.
Email required Address never made public. Name required. A small blog of a young programmer Here you will find posts related to.For a scroll bar which can be used comfortably with touch UI or fingers we need to change its default template.
You are commenting using your WordPress. You are commenting using your Google account. You are commenting using your Twitter account. You are commenting using your Facebook account. Notify me of new comments via email. Notify me of new posts via email. Skip to content The default scroll bar for WPF is a normal bar with two arrows on each side. Following are the steps to achieve a scroll bar as shown above 1.
Add it in your resources and update the parts of scroll bar accordingly: Remove the repeat buttons from top and bottom Curve the edges for track and thumb Increase the width of thumb, so that it is easily accessible by finger Change opacity and color levels on track and thumb add control triggers for opacity level change on mouse-over and dragging of thumb 3.
Below is the complete style along with its usage, XAML only implementation. Share this: Twitter Facebook. Like this: Like Loading Leave a Reply Cancel reply Enter your comment here Fill in your details below or click an icon to log in:.
Anyways to cut a long story short I decided to try and have a go at Styling a bigger control such as ScrollViewer. And guess what I managed to do it. This blog entry outlines the steps I went through. I then decided which parts I want to swap out. So basically after that, its just a question of cutting code. So withour further ado, here is the code. And if you want to try this for yourself, here is a VS demo project scrollviewertemplate.
Were you required to write all that XAML manually or is there something in VS that makes this process more time efficient apart from intellisense?
WPF - Scrollviewer
This accounts for most of what you see here, apart from the Brush stuff maybe. However Blend creates some bulk that you would not get by hand coding. I am more of a Designer, not much into Xaml at the moment. So my question is, did you overwrite the standard-styles of the Scrollbar, as it would be normally? How do you go about that? Could this little square becomes transparent?? Congratulations for all you wrote, that is very helpfull for beginners and thanks for taking time to read this post with an ugly english.
You know I am a developer, not a UI expert. So if you want rid of that box, set it to transparent. For me I prefer code…I do delve into design from time to time but mainly I code. So these sort of things dont worry me…but if it worries you then you can fix it.Here: I dragged three Button controls to the ScrollViewer. I then added margin to the Buttons to make them larger in area.
Result: In the final program, the buttons can be scrolled up and down with the scroll bar located on the right of the window. And: You won't need to redesign your entire program just to add another button or TextBlock description. A ScrollViewer scrolls other controls.
It is used as a container. We drag or otherwise add controls, nesting them inside the ScrollViewer. And then it automatically allows scrolling of the interior area.
To use a ScrollViewer please open the Toolbox and drag the control to your Window. The ScrollViewer is worthless with no internal controls. So try dragging some Button controls or any control to its interior area.
In a StackPanel, controls are "stacked" in one direction. Other controls, not just StackPanel work just as well within a ScrollViewer. ScrollViewer is a layout control. It requires you to add controls to it before it is useful. Once you do this, though, you get a region that expands as much as needed. This can lead to more versatile interfaces. Button TextBlock. Sometimes when designing programs, a "Preferences" dialog Options is a burden. At first, these windows have few controls.The default appearance of the scrollbars in the WPF ScrollViewer is ugly and gray, and often appears too large and obtrusive when used within a smaller control or dialog.
There are several articles on how to re-style the scrollbars, but all of them seem to require vast quantities of code, and I hate to pollute my code base like that for such a seemingly-trivial task.
By changing the Opacity of the scrollbars, which is a relatively small style change, one can make the scrollbars blend in with the overall background color of the controls on the window. And because there is no text in a scrollbar, its appearance does not resemble a "disabled" control.
The thickness of the scrollbars can also be changed in the same code fragment. You can create a few styles to match your particular circumstances - for example, you probably want thinner scrollbars only within smaller controls, because they are more fiddly to click.
Here are some more examples showing different color saturations and how transparency can help blend in with the background color:. I admit that even the above code seems bemusing and far too much effort for such a trivial change to the GUI, especially for beginners who already have enough to take in just learning WPF basics.
But once you see how the scrollbars are constructed internally, it starts to make sense, and we are lucky that we can restyle them at all. I would welcome simplifications here if you have any tips. The WPF slider control's appearance is equally bemusing to alter, and I can provide a style for that too, if anyone is interested. It uses the same idea of changing the opacity within its target style.