is there any way to make winforms listView showing data like treeView. i mean to make it verticaly oriented and to show columnHeaders one under another and not to put them in horizontal line?
thanx for assistance
Consider using this open-source ObjectListView.
It's a mature control that can show all sorts of lists, a tree-list and much much more (not my code - I'm just a happy user).
It take a few minutes to get used to the idea of using it, but once you got it - using it is a breeze.
Examples:
You can also consider using Better ListView. The usage is 99% same as the original .NET ListView, but it has many extras. For example, every item has a ChildItems property in which you can put further children.
Related
I know this is a stupid question, I need to let you guys know that I am fully aware that it is useless in 99% of situations to make a listbox with this many elements in c#:
That being said I need this to be done...is there any way to populate a listbox with 40000 elements without it completely destroying performance/freezing up, thanks!
note: I have tried it, this is per the exact requirements of a professor...when adding 40000 elements through a DataSource and DataBind the application freezes up
You tell me.
for(i=0;i<40000;i++)
{
listBox1.Items.Add("click me");
}
Even if is possible (I never tried it), the usability for this form will be 0.
In that cases a more usable implementation is via lookup text-boxes and lists, where the user can enter a text to search record that matches this text and displays them in a any kind of list.
It is of course possible to do it, but not very practicable.
When using a desktop technology like WinForms or WPF, for a large number of items like this you are better off using something like an auto complete textbox, and have it set to filter/search after the user has typed two or three characters. In this case you can also use a control that offers scrolling virtualisation - this means that there is only a limited number of UI elements created in the scrolling portion of the dropdown, and those elements get reused when a scroll occurs. If you don't use virtualisation then a new element gets created for every list item that gets scrolled in to view. (Note that Silverlight controls have this functionality - just in case it's an option).
For ASP.NET though I would suggest that you do not want to do anything that would cause a large transfer of data (large items, or small items but lots of them) as it won't be performant. Instead you should look to do what Google does - retrieve search results in a paged fashion.
I have two doubts about the autocomplete feature of textboxes in C#.
First, I want to display the full list, not only the ones that start with the given text, and secondly I want to prevent the auto-complete of specific options (some are category titles).
I've been checking the textbox properties and there's nothing related to it, so probably the main question could be, Is there a way to modify / override the textbox events in order to handle the auto-complete actions? (I don't know if it applies to show the full list too)
I assume you're asking about a winforms textbox, as I dont think the WPF textbox supports autocomplete at all.
The base TextBox class will not support doing what you want, so you could in theory attempt to override all of the functionality in the TextBox class to do what you want, but the better idea would be to create a new custom control that inherits from TextBoxBase and implement the autocomplete behavior the way you want it.
I'm not sure about displaying the full list (perhaps a combobox or similar is more suited to this?) but you can definitely do something like this to swap which list of possible items can be displayed.
Another option, though one I like less, is to remove items you don't want to display at a given time from the collection dynamically, like this: textBox.AutoCompleteCustomSource.Remove("ACategoryTitle")
I could foresee that approach having many problems with trying to rebuild the list constantly. I would probably create a subclass of AutoCompleteStringCollection that wraps some LINQ code to nicely select the union of some lists and not others to display in the textbox.
I decided to build my own autocomplete tool with the help of a simple listbox and events, then I could achieve what I was expecting..
The CodingGorilla's answer probably leads to a better solution if you want something more decent, in my case for speed reasons I decided to do it that way but I'll mark his answer as the accepted in order to help other people who have the same doubt and they could consider that point..
I'm trying to get a combobox in winform that has around 5'000 entries. I've run into a problem before - addrange hangs with this many entries. I created a seperate control to do this for myself without lagging, but I'm adding this functionality to existing comboboxes.
I was looking up VirtualizingStackPanel for WPF when trying to see if I could get around this.
Is there a way to improve the performance of addrange for a couple of thousand string entries?
Have you tried using ComboBox.BeginUpdate and ComboxBox.EndUpdate? Using those methods improves performance when adding items.
Of course, if you have 5000 items then maybe using a ComboBox isn't the right control (having more than 200 items or so makes scrolling impossible, which defeats the point of having a drop-down selector). Have you considered using a normal textbox but with an autocomplete provider instead?
I'm trying to learn WPF and was thinking about creating a simple IRC client. The most complicated part is to create the chat log. I want it to look more or less like the one in mIRC:
or irssi:
The important parts are that the text should be selectable, lines should wrap and it should be able to handle quite large logs.
The alternatives that I can come up with are:
StackPanel inside a ScrollViewer where each line is a row
ListView, since that seems more suitable for dynamic content/data binding.
Create an own control that does the rendering on its own.
Is there any WPF guru out there that has some ideas on which direction to take and where to start?
I suggest you start with a good object model independent of the UI, and then try a multi-line TextBox or a RichTextBox.
Whether these will suffice will depend on exactly how long you want the log to be able to get. If you run into performance issues, you may need to look at virtualization.
First of all, you should consider if you want to select only entire row (like in a listbox), or if you want to select certain characters from a row (like in a textbox).
In the first case, I think a ListView or even a ListBox should be enough, both of them support virtualization when bound to collection and there should be no problem with huge amounts of data. A stack panel inside a ScrollViewer is a little bit like reinventing the wheel for this case and creating a new control is not a very inspired approach in my opinion (as the functionality you want can be achieved with the existing controls, in WPF).
In the second case, if you want to select some text inside of a line, or if you want word wrapping for your longest lines in the log and want to select individual parts of the wrapped lines, then you need to use a control more oriented on displaying text. Kent already suggested a RichTextBox, I would add AvalonEdit control or even the WebBrowser control in which you directly modify its HTMLDocument.
I would suggest to use RichTextBox too, and store items in a log file or database, if you run into performance issues.
Another solution is to use the WPF WebBrowser control and modifiy its HTML content with:
webBrowser.NavigateToString("<HTML><H2><B>This page comes using String</B><P></P></H2></HTML>");
More information about using WebBrowser control
I have a class that returns a list of "Category" Objects. I'd like to display them along the left-hand side of the page in a listview (if that's the best way to do it, even).
The category objects have normal attributes. Title, User, NumberOfProjects. I'd like to display both the title and the number of projects in this list.
Not worried about editability right now as we might make that separate (i.e. not in-line in a list view edit mode).
What do you think is the best way to do this?
Thanks in advance for any help you can give! :)
First if the array of the objects is too big I'd recommend to use virtual mode of ListView.
Second, nice way to "convert" youur object to string is to override ToString method where you can represent info of your object.
One alternative is to bind your collection to a DataGridView and display that, which would save you having to load each item manually but looks tacky and like it was made in Access.
Personally, I'd use a list view as you've suggested. I find that although you have to load its items manually, its simple and looks by far the most professional.
I was just looking for the best way to use a ListView control, I suppose.
I was able to figure it out -- I wasn't using correctly and hadn't included a "contentPlaceholder" element.
After doing this, I was able to use <%#Eval("FieldName")%> to insert the object's properties into labels. It was already in list format, so the databind was a snap.
If code would benefit anyone else, I'll post it -- I just didn't feel like cutting out all the extra CSS. ;)
Thanks to everyone who tried to help with this!