How do I create a WPF Dropdown panel - wpf

I'd like to create a dropdown panel in WPF the acts like a ComboBox/Expander hybrid. I'm currently using an Expander but it pushes the the controls underneath it down when it expands.
I simply want it to act like a ComboBox and overlay it's dropdown. I've looked at using Popups but they don't move with the underlying window when it's moved.
So, I've concluded that the closest control to my needs is a ComboBox which allows me to put a Grid or StackPanel into its dropdown area.
Any ideas how to achieve this?

I am not exactly sure what you want to do:
But the layout depends very much on the parent control. If your controls are in a Stackpanel all controls will be moved if a control expands or changes its size. If you use a Canvas you can align controls on top of each other.
Also Adorner are useful when you want overlay something above something else.
You can change the appearance of the ComboxBox and you can put a grid or anything else inside it. Have a closer look at ItemTemplate.

Related

WPF Adorner Overlay Problem

I am trying to achieve functionality similar to that of a Popup, without using a Popup, but instead adorning my ContentControl with a basic adorner. Basically, I want the ContentControl to have an "overlay" effect, whereby it is the topmost object, above all other elements - similiar to that of the Popup control.
Here is the problem that I am running into, and I am hoping that someone can point out where I am going wrong:
I have a stand grid with two row definitions. The first row contains a UI element - for example, a rectangle. The second row contains a custom control that I have developed to emulate the functionality of a "drawer" sliding out. Basically, when I click on button, I am going to animate a TranslateTransform to "slide" my ContentControl "up". This works fine - except that it gets cropped underneath the rectange in the first row of the grid. If I remove the row definitions in the grid, then when the desired behavior is achieved - the ContentControl is moved "up" and partially "on top" of the rectangle. The rectangle is merely a place holder for what I am trying to achieve. I basically want to have a drawer type control that can slide out and be on top of all other controls.
I am somewhat new to using the Adorner class, so, I am hoping that someone can please point out where I am going wrong.
Thanks.
Chris
Change the parent of the adorner to the full grid, and not just your control. If you put a control in a grid row, and set the adorner to adorn the control, it will usually be clipped to that row because the control is.

WPF contentcontrol extend beyond the bounds of its parent control

This is a sort of extension of this question I asked yesterday (the question gave me a contentcontrol that can overlay the current control). I now have a contentcontrol that can be overlayed on the current control via bindings (a modal type window). This works well and I am happy with this. One great feature would be if I could get the overlay to go over its parent.
currently the overlay will go into "My Control" control. What I would like is if I can still define it in that control (as that is were it is needed), but when it is displayed it can cover the whole main content area and / or the main window.
is this even possible?
Thanks
Sure it's possible, just wrap it into a Popup! :) You might have to manually stretch it though, but Popup is the control which will let you go outside the bounds of the parent view.
Another way is to host the MainContent in a grid and add a collapsed content control after the MainContent.
To show the popup: put it in the collapsed content control and make it visible.
To hide the popup: collapse the contentn control and remove the popup.

Is it possible for WinForm controls (Panel,etc.) to grow like a webform control?

I'm converting an app from ASP.NET WebForms to WinForms. There is one asp.net page which contains a ListView/Repeater that contains several custom controls, which in turn contain a ListView with other custom controls. Basically the layout looks like a TreeView, but on each node/leaf there are few controls like comboboxes, etc.
When this is in ASP.NET, the page automatically lays itself out, so it is several screens tall - if I add 20 buttons into a Panel, it will grow and the browser will get scrollbars.
I'd like to do the same thing in a WinForms application - so I'll have a user control that will contain a lot of controls in a some variation of Panel (Flow, Table layout), and the controls might have another controls inside them, etc.
The problem is, that when I make winforms app, each control has specific height in the design time. I'd like some user controls to be able to grow with their contents - so they'll add up. In the main Form, there should be a vertical scrollbar, just like in the web browser when the generated page is taller than the screen.
I'd just like to get some general pointers in the right direction. Thanks.
Use Anchor and Dock container properties.
Yes, to expound on Anchor and Dock...try this
-Place a Panel on an empty form, and set its dock property to Top
-place a textbox in the panel, and Dock it to Full...it should fill the whole top panel
-Place a splitter on the form, and if not already docked correctly, set its dock to top
-place another panel below the splitter, and set its Dock to Fill
-place another textbox inside the lower panel and fill it as as well
Now you have a form with two resiable textboxes and will resize when the form does.
*you may have to set the textbox MultiLine property to true but not sure.
Hope this helps.
Anchor the controls to the parent. Anchoring all four sides will cause it to stretch.
If the Anchoring and Docking answers don't work for you, there is another option. It's not pretty, but you can access a control's properties and change them dynamically during runtime. You'd do something like: if(listBox.Items.Count > [yourVal]) listBox.height = [yourFormula] or something.
It's been a while since I've done a Win Form (and I don't have my IDE fired up at the moment) but I'm pretty sure there's even a ScrollPanel or other scrolling control that you can set on your form.
That said, when you're working with WinForms, the less scrolling you can make your users do, the better.

When writing the xaml for my user controls should I remove grid and use dock panel or something else?

I am adding user controls in my solution. The main page of my project will have a dock panel. When writing the xaml for my user controls should I remove grid and use dock panel or what? Iam using visual studio express and WPF.
The answer is it depends on what you want your control to look like.
Remember the Grid is to help you orgainze your controls. You can define features like columns widths, row heights, and other styling.
While a dock panel is to help dock your control to a part of the form or another.
So it depends on what you want your control to look like. You can nest a grid in a dock panel and vice versa. There is no set rule. It is really up to you.
Inside your user controls, use whatever type of panel makes sense for the contents of that control. In the main page, you set the DockPanel.Dock attribute on your user control, but that is independent of what's inside the user control.
It really depends on what you want to do.
Your top level may not even be a panel. For example, if you only want one control in the user control, then you really don’t need the panel.
Also, in some cases, even with composite controls, you may want to put something other than a panel as the top level control, for example, an expander.
Further, if you want to create a control that is very similar to another control, but behaves a little different, you may not even want to use a user control and instead inherit from an existing control. An example of this would be a numeric textbox that inherits from a textbox but adds keypress filtering.

WPF page layout control selection

I have an imagebrush of a soccer field as the page background and I want to be able create a line up by dragging players off the bench and positioning them on the field accordingly. I don't know what control to use for the background that allows the PlayerCard control to reside where it is dragged. Any help as to how to begin would be appreciated.
You can get the idea here.
What control to use?
I believe you want the Canvas container control. It lets you arbitrarily place child controls with a Left and Top attached property, similar to the way Windows Forms does it.

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