I'm working on a media library mock-up and I have a database of songs (over 9,000 tracks) that I want to display and make sortable. I'm not sure which GUI control would be best to use and I am not sure how it would be best to add all of the entries to the control.
Obviously using a listview and adding each entry one at a time takes a long time. Currently, the database is returning all of the tracks in an array of media objects (mediaEntry[] - a struct I defined). I don't know much about .NET's databinding system and any performance benefit that may bring.
The database is also searchable so I'll be changing the information displayed in the GUI control depending on the search terms.
Something like DataGridView or ListView in "virtual mode" should work well; this avoids the need to process all the data up-front.
however - I doubt that mediaEntry should be a struct - sounds like a class to me.
It is very rare you write a struct in .NET
The Listview control has a virtual mode, where you supply the viewable data on demand. Its actually easier to use than it sounds. Checkout the VirtualMode property and the RetrieveVirtualItem event.
You may want to give ObjectListView a try. It's very handy to use and has excellent performance when used appropriately.
Note: I'm not the developer of this library, I'm advertising it just because I used it in one of my projects.
Related
I have a WPF application, and it's slow.
It is NOT the rendering. Firstly, the rendering is quite simple, and secondly, I looked at it with WPF Performance Toolkit - nothing.
It is NOT in my own code. Firstly, the unit tests work fast, and secondly, if I replace all DataTemplates with blank ones, everything works fast.
So far, it looks like the slow part is template instantiation. That is, when you start the application, and open some complicated screen, it takes a lot of time. And by "a lot" I mean "a lot". Sometimes can be as much as 3-5 seconds - for example, when there's a datagrid with 100 rows. But when you go to another tab, and then go back to that same screen, it opens fast (as long as its viewmodel stays put).
This is very annoying not just because it's slow, but because I can't do anything about it. If I had some control over the slowness, I could, maybe, display some "opening, please wait" message or something...
Besides, when I look at some other WPF applications (most notably, ILSpy), they seem to work reasonably fast, despite the large amounts of data. This makes me believe that I'm probably doing something wrong. But I have no idea where to start.
Any ideas? Any classic mistakes? Any tips?
My exerience comes from working on the WPF mind mapping application NovaMind
A couple of months ago we completely rewrote our intermediate layer to solve the performance issues we had experienced. In a nutshell, creating our user controls seemed to be way to slow. Unfortunately I couldn't find a great way to profile the performance as neither the WPF Performance Suite nor commercial applications such as ANTS Profiler give you any detailed information on this part of the WPF process. (I asked this question back then)
We resorted to manually test our application by trial and error and removed parts of our user controls to see what exactly is the culprit.
In the end we solved the performance issues by completely rewriting our controls. We also cut down on the complexity of our visual tree dramatically. Before the rewrite, one of our most used user controls, when inspected with Snoop, consisted out of 61 different things, now there are only 3. Wherever possible we only added things to the visual tree on demand. (As you know in XAML even when you set things to Collapsed, they need to be created first).
Finally we were forced to write our own rich text rendering control as the built in RichtextBox is ridiculously slow and the visual tree of the RichtextBox is quite complex.
I don't know if this will apply to your situation but I would recommend that you investigate your user controls and see if they are complex. Maybe you have things that you could trim.
Low hanging fruits would be parts that are only rarely visible or can be created in a lazy manner. You could create these parts from code behind when necessary rather than having them in XAML. This should help you a lot.
Otherwise virtualization is your friend, if possible. In our case we couldn't do that unfortunately.
This sounds similar to a problem i was having. I posted the fix here: WPF UI Automation issue . Just posting for the benefit of searchers, as it took ages to resolve.
Following comment on link only answer, here is the crux of that post:
I did the following:
Downloaded Hotfix - - http://archive.msdn.microsoft.com/KB978520 (may not be required)
Downloaded Hotfix - - http://archive.msdn.microsoft.com/KB2484841 (definitely required even if you have Windows 7 / .NET 4)
Improved the code further (the validation was causing an excess of objects) - Why does WPF Style to show validation errors in ToolTip work for a TextBox but fails for a ComboBox?
It may be that only Number 3 was required, but it worked. Just posting here so people dont lose the days I lost in memory profilers etc.
User Control in your data template, is not completely bad idea but if you crave for performance then you should consider switching to lighter control. For example, having a UserControl just hosting a TextBox is very bad idea, as UserControl is made up of ContentControl, ContentControl hosts ContentPresenter and ContentPresenter will host TextBox so if you notice your Visual Tree, it has three new layer of UI Elements. Reducing Visual Tree will certainly improve the performance.
Most likely, I would suggest creating Custom Controls that may be a completely a new control having few dependency properties that can relate to data you want to present and you can have its own custom template in generic.xaml. Second, you can just simply derive a control from existing controls and redefine its default template in generic.xaml.
This approach will certainly work better as you will be reducing your Visual Tree, thus reducing Visual State Manager's job.
Changing theme or template will be slower then changing the element that hosts content. And let the element have the default template in its own generic resource dictionary.
Try moving all the resources up as
far as they'll go, preferably into
app.xaml
Check if you could use StaticResource
instead of dynamic ones, static ones
are alot faster
If possible, try using depedency
properties in your VMs, especially if
you have alot of them at once or if
they have alot of properties. That will keep wpf from having to do a bunch of reflection.
You mention you are using a DataGrid with, say, 100 rows. A likely culprit of your perf problems is that whatever datagrid you are using isn't doing virtualization, and so your visual tree is gigantic.
Normally, long startup time in WPF screens points to a large visual tree.
I'm not sure if you're using a datatemplate per row, or some 3rd party grid that binds columns, or what - but lets say you have 8 columns with controls. Depending on your grid/validation/etc, this could be a visual tree of 20-60 items per row. If you have a combobox, then each item in the dropdown may be created per row as well.
To fix this just takes watching the details, and taking measures as you go:
Use a virtualizing control as much as possible. This means using a virtualizingstackpanel inside list controls, and making sure your 3rd party controls do as well (many stock WPF controls do now by default)
Do not overuse UserControls, composite controls, etc. Adding depth adds time, and putting in extra visual tree depth in a datatemplate or other repeated area adds up fast.
If all else fails, show a simple screen and add controls through code to improve perceived performance
Does anyone know of a good listview component other than the one included with Visual Studio (as it looks kinda boring)?
Devexpress are good too. http://devexpress.com
(Quick edit missed the Winforms bit). For Winforms controls, I'd recommend Telerik.
If you want to modify the look of your form and controls try DotNetSkin. You can modify controls from existing windows themes or your own controls by modifying it.
If you want a free ListView, you should try ObjectListView, it has a LOT of features.
You better be careful about the license if you want to use it in a commercial product though. See these answers for more information about the license: here and there.
You may try Better ListView.
It has native look and feel. It also supports many nice features, like hierarchical items, multi-column sorting, data binding, three-state check boxes... the list goes on :-)
It is not a ListView wrapper, but self-contained control so it fixes all inherent flaws of .NET ListView (these are enumerated on ComponentOwl's website).
Take into account the 10Tec iGrid control:
Its main features are:
Multi-column sorting with indication in column headers.
Grouping and autofilter are also available.
"Subitems" (cells) can be edited.
Rows can have different heights.
Rows/cells can be formatted dynamically easily.
Built-in incremental search.
TreeListView mode.
No flickering and fast work with 100'000+ rows.
To find out more, start from reading this article:
Editable ListView Replacement
See also other cross-referenced articles on the site.
I'm writing an application that needs a log-like view, (similar to how an IM client displays messages in the conversation), with potentially many updates per second. Speed is an issue here; the application locking up due to a large number of incoming events is a possible problem. I need selection and basic text formatting, so manual rendering could get quite complex, I'd like to avoid it if possible. I'd also like to bottom-anchor the scroll bar, that is, if it's at the bottom, stay at the bottom when the new item is added. What would be a good way to implement this?
You can implement it very easily in WPF.
Create an ObservableCollection of Log entities and bind to a ListBox.
Give a DataTemplate for the ListBox.ItemTemplate.
*When running in real time you need either UI side or Data side virtualization
Check out my PaginatedObservableCollection so that the DataVirtualization will automatically function.
I think you should have a look at ListView/ListBox controls, they support UI virtualization and provide functionality you're looking for. Also you can improve performance by data virtualization/lazy loading - i.e. don't hold invisible items in memory and load required data on demand
I know that I can't use this web control in my C# windows application and that I am restricted to DataGridView control. But this does not display results in an elegant manner as the Web.UI.Webcontrol.GridView control but instead displays it like the results when a SQL query is executed in sql server.
I prefer not going down the path of hosting a webuser control which in turn would launch my website using the Web.UI.WebConntrol.GridView control.
You can make the DataGrids look a lot nicer than the default, this MSDN article explains some methods you can use, mostly by changing the available properties, and making use of the DataGridTableStyle and DataGridColumnStyle.
If you want to implement paging, and are working with a read only dataset, you can look at this knowledge base article.
Finally, if you've got money to spnd, there are many companies selling a version of a datagrid control that will look more like the web control, Syncfusion and DevExpress are just two, although I've not used them myself, so can't say how good they are
Somewhere on net on one Blog I read a sentence that is "DataGridView something like Boeing 777, but what is goal when I do not know how to fly.
Before I goo deep in creating my projects I wanna know is there alternative for DataGridView in C#.
Something like jQuery in WEB api.
The favors things which I am looking for is that is simple for using, if its posibile to be freeware and looks smoth and modern.
Best regards
Admir
If you want to fly one person across town you can learn to fly a Piper Cub. If you want to fly hundreds across an ocean you need to learn to fly a 777.
There are many ways of displaying data in WinForms applications; which one is best for you depends on what you're trying to do. If you want to show a fixed, non-editable, non-scrollable list of data you can use a DataList; simple and limited. If you want to add scrolling you can output the data to a scrolling textbox.
If you want to handle a scrolling grid of multiple rows with multiple, resizable, editable columns you will need to move to a DataGrid or DataGridView.
There are many alternatives to DataGridViews; simpler controls provide fewer features and more functional controls are more complex.
I have implemented the datagridview extensively as an unbound control in a windows forms project using Visual Studio 2008. Looking back, implementing this control has consumed a large amount of time, mostly because it is loaded with bugs and peculiar behavior that should have been fixed rather than just 'documented'. A good data grid control is essential to any application of substance. I would recommend looking for a third party alternative from a company that is more interested in getting it right rather than just getting something out there.
The DataGridView is perfectly easy to use without going too deep. If all you want to do is display data in a grid, create a DataGridView and turn off features like adding and editing rows. The fact that it's got all of these incredibly complex features is really only an issue when you start needing to use them - and in that case, you'll be glad you're using it.
DevExpress has a really good gridview.