WPF tooltip virtualization - wpf

Is there any way to virtualize tooltip in WPF? I have many dataitems displayed on map. When i'm changing template, for example, it takes a lot of time to generate UI for tooltips that are invisible. Maybe wpf supports something for such cind of virtualization?
Thanks in advance.

The way in which I've done this before is to generate a tooltip that is very simple, with a container item as the root and a simple single textblock inside, and then hook into the loaded event on the textblock, to detect when the tooltip is trying to be shown.
At that point, I then generate the full tooptip on the fly and replace the contents of the container, removing the textblock placeholder in the process.

Related

Multiline Combobox Control in WPF

I would like to build a multiline combobox in WPF. This would be similar to label control wherein the width of control will grow such that entire selected text is visible. The text displayed can go over next line if there is no enough space available on current line.
I tried few things around control template of combobox. But still no success.
Below is sample screenshot of how it should look like!
Any pointers?
Thanks,
Sambhaji
As per my understanding setting the control template for this particular scenario would be a tedious job. I would have created a TextBlock and tried setting the event triggers which will open a container on mouse hover or click event.

Can we overlay a WPF element by another?

I've this situation:
A label placed in Footer Cell of a RadGridView doesn't have sufficient width available in its container for displaying its full text.
Is it possible by any ways to have the label cross its container boundaries and show full text?
Thanks!
The space given to any element depends on the parent control or Panel that contains it, as well as its Width, Height, Horizontal and VerticalAlignment, and Margin. Normally you can manipulate some combination of these directly to change overlapping behavior but by using a DataGrid control you've given up a lot of that control since things like ColumnSpan are set up by the control internally. You could try setting negative Margin values and changing the Panel.ZIndex but I doubt those will help.
The best solution I can recommend without more detail is to use TextWrapping or TextTrimming to avoid ugly clipping, maybe in combination with a ToolTip showing the full text.
You can overlay any WPF element by another anytime. Only place where it fails is the WebBrowser control .The WPF WebBrowser has not been improved a single bit from WinForms WebBrowser. It is still the same simple activex control. However, you can bypass even that with a tooltip control.
I believe you can either set ClipToBounds=False to allow it to expand outside its area, or set TextWrapping=Wrap to allow the text to wrap.
EDIT: Forgot ClipToBounds is only honored in the Canvas control, so wrap your label in a Canvas and set ClipToBounds=False and it should work.

Silverlight TreeView in ComboBox (or just a custom dropdown control)

I was wondering if I can have a ComboxBox with a Treeview as the selector rather than a list?
I note that there is a ComboBox.ItemsPanelTemplate, but I don't know what I need to do to get this to work?
I could build a control 'from the ground-up' with a separate TextBox, Button and TreeView in a PopUp control, but wondered if there is an easier way.
Lee
Are you just wanting the combobox for presentation purposes regarding the treeview?
Why not use a treeview as is and just trigger the display via visibility or animation from a button or control of some sort?
I am working on similar theme as we speak. I am using the Expander control from the Silverlight Toolkit with a TreeView control inside it. When an item is selected in the TreeView, it sets the Header of the Expander and then collapses the Expander.
Initial tests indicate it's OK but as I say, just started with it myself. Will let you know if I hit any stumbling blocks.

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.

WPF Rendering performance

I have a WPF User control that binds to a DataTable and generates CheckBox and a masked EditBox for each row in a DataTable. I have several instances of this control on my form. The total number of CheckBoxes to be generated is over 200. I am seeing some rendering performance issues. The form loads with all of the static controls ( Text Boxes, Drop Downs) instantly, then several seconds later the CheckBoxes appear.
Any thoughts?
Thanks
Unless all the 200 items are visible on the screen, you should be using some kind of virtual layout that creates the visual tree only for the visible items. This will greatly improve your performance.
What is "generating" the checkboxes? You should be using an ItemsControl (or subclass) and binding the data that represents the checkboxes to it. Assuming you're doing that, then what you want to do is get that ItemsControl to use "virtualizing" by applying the VirtualizingStackPanel.IsVirtualizing property to the ItemsControl like so:
<ItemsControl VirtualizingStackPanel.IsVirtualizing="true" ... >
You might also want to turn on "container recycling" which will also help performance. This is also done with an attached property:
<ItemsControl VirtualizingStackPanel.VirtualizationMode="Recycling" ... >
Too many checkboxes surely cost a lot, if you look at templates of basic controls, they are also filled with lot of uielements.
I would suggest if you can divide your UI into Tabs or Accordins that will cause less visible items on one screen as well as it will help user navigate to items easily and faster as well.
VirtualizingStackPanel will help but if your binding isnt correct it may lead to unpredicted results.
Custom Control Template:
You can also create your own custom checkbox template with least UIElements, like simple rectangle filled with different color on IsChecked property trigger. This will eliminate few animations etc that can surely imporve your rendering performance. I believe CheckBox is least important when it comes to animating UI.
When you are sure that you will be using "Text" as content, then simply create template with rectangle to show filled/empty value and put TextBlock with template binding to Content.
Try to give fixed width/height to your checkbox, whenever you fix the height/width of your controls/containers, it becomes eaiser for layout manager to render them, rather then keep on calculating and adjusting items.

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