I have a TabControl with several tabs. The first and main one is very simple one and takes virtually no time at all to load. The second one on the other hand is a representation of hundreds of complex objects, and takes about 1-3 seconds. The application fires up rapidly, but as soon as you click on the second tab, the application freezes for a short while, loading the Tab Control.
This is a quick illustration of the XAML code:
<Window x:Class="MyProgramme.MyMainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Grid>
<TabControl VerticalAlignment="Stretch" Grid.Column="0" Grid.Row="0">
<TabItem Header="Simple View" >
<!-- Main view. Loads instantly. -->
<ContentPresenter x:Name="m_simple"/>
</TabItem>
<TabItem Header="Heavy View" >
<!-- Takes about 1-3 seconds to load-->
<ContentPresenter x:Name="m_heavy"/>
</TabItem>
</TabControl>
</Grid>
</Window>
Obviously, this waiting is not very user friendly, and I would like a way to explicitly load the second tab whenever it's convenient, which will be either at start-up, or whenever the UI thread is not too busy and can take the load. Is there a way of loading this tab without stalling the user's work flow?
If you are loading the data for the tab in the constructor, that would be the reason for the freeze.
Rather use the Window's Loaded event instead and if possible, try kick off the heavy load in a background thread. Loaded is triggered once the UI is drawn leading to a better user experience as the UI itself does not appear to freeze.
You should also consider a BusyIndicator or ProgressBar for the second tab while the background load is running to indicate to the user that a long running process is happening.
Related
On my Window, I have a ViewBox control, which contains a custom progress bar. I set its Visibility to Collapsed in design mode, because I need to display it in only certain moment (during login into app).
In my progress bar, which is usercontrol, I have event handler for VisibilityChanged event where I stop and start my animation.
When user clicks on the Login button, I need to show this ViewBox until Login is completed and collapse it again after success. But, when I (in code behind) set ViewBox.Visibility = Visible, it doesn't show up.
Can anybody tell me why, or how to fix it ?
XAML:
<Viewbox x:Name="cpProgress" Width="50" Height="50" HorizontalAlignment="Center" VerticalAlignment="Bottom" Grid.Row="1" Visibility="Collapsed" >
<lc:CircularProgress />
</Viewbox>
Thanks
change ViewBox.Visibility = Visible to cpProgress.Visibility = Visible and ensure that the Grid has a proper row height defined for row 1.
I've finally come to solution of this problem. It is really simple :).
I've just forgot that If I run the login process in same thread, as my window is in, the UI will hang until the login is completed. So solution is to spawn a new thread,run the login in its context and wait for completed flag to be set in UI's thread. The login process has to be running in asynchronous manner, so the UI could draw my usercontrol.
I'm making application in .NET C#.
It is not my choice but it has to be "multi-tab" application.
I have one window with tab control with many tabs.
There are many controls on every tab. Now all my event handlers and stuff is in main window file.
How to manage this program.
Is there any way to keep content of every tab in separate file (maybe class)?
Can use a frame and reference a page or user control
<TabControl>
<TabItem Header="Tab1 Page">
<Frame Source="TabPage.xaml" NavigationUIVisibility="Hidden" />
</TabItem>
<TabItem Header="Tab2 User Control">
<Frame Source="UserControl1Tab.xaml" />
</TabItem>
</TabControl>
A User Control is probably cleaner but I use Page out of habit.
They both have code behind for event handlers.
If you need to pass data then can do it in the ctor (but then you cannot assign the Source in XAML).
We are using the prism and WPF to build application. Recently we started using UI Automation (UIA) to test our app. But some strange behavior occurred when we run UIA test. Here's simplified shell:
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<TextBlock
Grid.Row="0" Grid.Column="0"
Name="loadingProgressText"
VerticalAlignment="Center" HorizontalAlignment="Center"
Text="Loading, please wait..."/>
<Border
Grid.Row="0"
x:Name="MainViewArea">
<Grid>
...
</Grid>
</Border>
<!-- Popup -->
<ContentControl
x:Name="PopupContentControl"
Grid.Row="0"
prism:RegionManager.RegionName="PopupRegion"
Focusable="False">
</ContentControl>
<!-- ErrorPopup -->
<ContentControl
x:Name="ErrorContentControl"
Grid.Row="0"
prism:RegionManager.RegionName="ErrorRegion"
Focusable="False">
</ContentControl>
</Grid>
In our app, we use layers (Popup and ErrorPopup) to hide MainViewArea, to deny access to the controls. To show Popup, we use next method:
//In constructor of current ViewModel we store _popupRegion instance to the local variable:
_popupRegion = _regionManager.Regions["PopupRegion"];
//---
private readonly Stack<UserControl> _popups = new Stack<UserControl>();
public void ShowPopup(UserControl popup)
{
_popups.Push(popup);
_popupRegion.Add(PopupView);
_popupRegion.Activate(PopupView);
}
public UserControl PopupView
{
get
{
if (_popups.Any())
return _popups.Peek();
return null;
}
}
Similar to this, we show ErrorPopup over all elements of our application:
// In constructor we store _errorRegion:
_errorRegion = _regionManager.Regions["ErrorRegion"]
// ---
private UserControl _error_popup;
public void ShowError(UserControl popup)
{
if (_error_popup == null)
{
_error_popup = popup;
_errorRegion.Add(_error_popup);
_errorRegion.Activate(_error_popup);
}
}
Mistics...
When we run it as users do it (double click on app icon), we can see both custom controls (using AutomationElement.FindFirst method, or through Visual UI Automation Verify). But when we start it using UI Automation test - ErrorPopup disapears from the tree of the controls. We trying to start the application like this:
System.Diagnostics.Process.Start(pathToExeFile);
I think that we missed something. But what?
Edit #1
As #chrismead said, we tried to run our app with UseShellExecute flag set to true, but this does not help. But if we start app from cmd line, and manually click the button, Popup and ErrorPopup are visible in automation controls tree.
Thread appThread = new Thread(delegate()
{
_userAppProcess = new Process();
_userAppProcess.StartInfo.FileName = pathToExeFile;
_userAppProcess.StartInfo.WorkingDirectory = System.IO.Directory.GetCurrentDirectory();
_userAppProcess.StartInfo.UseShellExecute = true;
_userAppProcess.Start();
});
appThread.SetApartmentState(ApartmentState.STA);
appThread.Start();
One of our suggestion is when we use method FindAll or FindFirst to search the button to click, window somehow cached its UI Automation state, and does not update it.
Edit #2
We have find, that extension method of prism library IRegionManager.RegisterViewWithRegion(RegionNames.OurRegion, typeof(Views.OurView)) have some strange behavior. If we stopped use it, this solve our problem particulary. Now we able to see ErrorView and any kind of view in PopupContentControl, and application updates UIA elements tree structure. But this is not an answer - "Just stop use this feature"!
In MainViewArea we have a ContentControl, which updates it content depending on user actions, and we are able to see only the first loaded UserControl to that ContentControl.Content property. This is performed like this:
IRegionManager regionManager = Container.Resolve<IRegionManager>();
regionManager.RequestNavigate(RegionNames.MainContentRegion, this.Uri);
And if we change the view, no updates will performed in UI Automation tree - the first loaded view will be in it instead. But visually we observe another View, and WPFInspector shows it properly (its show not a UI Automation tree), but Inspect.exe - not.
Also our suggestion that window use some kind of caching is wrong - caching in UI Automation client we have to turn on explicitly, but we don't do it.
I'm sorry that I've missed some detail, that was the key to the answer. I think that it was not important thing. Anyway.
We used NavBar from DevExpress controls library for WPF. What turns out, is when NavBar is present, dynamically created views are not appears on the UI Automation tree. When remove it from the window, there was an ability to see all dynamically loaded views. What does the NavBar - still mistic for me.
Here bright example to see what happened, if NavBar is present or absent on the Window (DevExpress is required).
MainWindow.xaml:
<Window xmlns:dxn="http://schemas.devexpress.com/winfx/2008/xaml/navbar"
x:Class="Test.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525"
>
<Grid Name="ContentGrid">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<!--Comment NavBar to see dynamic control in UI Automation tree-->
<dxn:NavBarControl Name="asdasd">
<dxn:NavBarControl.Groups>
<dxn:NavBarGroup Header="asdasdasdasd" />
</dxn:NavBarControl.Groups>
</dxn:NavBarControl>
<TextBox Grid.Column="1" Name="Statictb" Text="static is visible in ui automation tree" />
<Button Grid.Row="1" Content="Create controls" Height="25" Click="Button_Click"/>
</Grid>
</Window>
MainWindow.xaml.cs
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
private void Button_Click(object sender, RoutedEventArgs e)
{
TextBox tb = new TextBox();
Grid.SetRow(tb, 1);
Grid.SetColumn(tb, 1);
tb.Text = "dynamic is not visible, if NavBar here...";
ContentGrid.Children.Add(tb);
}
}
Edit
According to the DevExpress answer on their support site:
After a peer is created, listening of automation events may cause performance issues. We have decided to clear invocation lists of automation events to resolve it. In your specific situation, you need to disabling clearing. To do it, please set the static DevExpress.Xpf.Core.ClearAutomationEventsHelper.IsEnabled property to False in the Window constructor.
This solve the problem.
My guess is that the ContentControl's automation peer should update its children with AutomationPeer.ResetChildrenCache() after the view has been changed.
AutomationPeer.InvalidatePeer() should have the same effect (in addition to other side effects) and it is supposed to be called automatically in response to the LayoutUpdated event. You might want to check that the LayoutUpdated event is raised when the view changes.
stukselbax, try to find a sequence of keystrokes (TABs, and an ENTER most likely) to click the button that enables you to see the items. it is pretty easy to send keystrokes and i can add more in here about that if that works for you. you can always establish a tab order in your application that makes the most sense for users.
------ Update on 6/20/12 --------
Have you tried double clicking a shortcut to your app on the desktop using PInvoke to see if you can see the controls when it is opened that way? Here is a link to an example here on stackoverflow:
Directing mouse events [DllImport("user32.dll")] click, double click
Another idea: some of the controls on the app I am currently automating don't show up in the tree until a mouse click occurs on them. To accomplish this without using any hardcoded coordinates, I find something in the tree which is just (above/below/etc) the place where I need to click to get the control to appear. I then get the mouse coordinates for that item and put the mouse at a small offset from there and click. Then I can find my controls in the tree. If the app is resized, moved around, etc. this will still work since the small offset is still valid.
So I have a Panorama control and the PanoramaItems are programmatically added to the control using the following template.
<UserControl>
<Grid x:Name="LayoutRoot">
<controls:PanoramaItem Name="sitePanoramaItem" Header="{Binding Name}">
<Controls:DockPanel VerticalAlignment="Stretch">
<StackPanel Orientation="Horizontal" Margin="0,10,0,0" Controls:DockPanel.Dock="Top">
<Image Source="../Images/action.png" Width="64" />
<TextBlock Text="{Binding Stats, Mode=TwoWay}" FontSize="45" Margin="15,0,0,0" />
</StackPanel>
<Grid x:Name="graphCanvas" HorizontalAlignment="Stretch" Margin="10,10,10,10"> </Grid>
</Controls:DockPanel>
</controls:PanoramaItem>
</Grid>
</UserControl>
When I click on graphCanvas what I'd like to do is sorta pop the graphCanvas out and display that fullscreen then when I click again restore it to where it was. I've been all over this site and Google and can't find anything similar to what I'm looking for.
I would still like to maintain the Panorama control functionality so that the graphCanvas is still the only one visible but you can cycle through them. Currently I have it sorta working in that I remove the Grid from the DockPanel and put it directly in the LayoutRoot while making the sitePanoramaItem collapsed. However, it's not fullscreen as the Panorama name is still visible (I guess I could hide that as well...) When I put the graphCanvas back int he DockPanel the size of the canvas is all screwed up.
I was hoping there was a simpler way.
Is it even possible?
It is possible to create the UI you describe but it's not going to be simple. You're on the right track with removing it in code and adding it the LayoutRoot and making the Panorama hidden. However you would have to code the scrolling behavior yourself and that is going to be quite tricky - especially making it feel the way to panorama does.
One trick you could try is actually layer a PivotControl on top of your Panorama and have it be collapsed by default. Also edit it's template to remove all default content eg: remove the header control, set margins to 0, etc). Then when you want to go full screen you can remove all the graphCanvases from the Panorama items and and add them to new PivotItems in the PivotControl. Then hide the Panorama and show the Pivot. This will give you scrolling capability for free and the illusion of full screen.
Having said all that I'm not sure I would recommend this. The more common approach would be to simply be to navigate to another page when the user selects an item and handle the full screen aspects there (possibly using the Pivot control again for scrolling). And when you want to leave "fullscreen" mode simply navigate back to the first page. Handling Tombstoning of the fullscreen state will be much easier with this approach for one thing.
You can try making the graphCanvas a Page and putting it in a different XAML. Then add a frame (name it InnerFrame for example) in the same place where you have the graphCanvas right now and navigate to that page with InnerFrame. When the frame is clicked, you navigate with the RootFrame of the app to your graphCanvas page. When you decide to close it, just navigate back with the RootFrame.
Hope it's clear enough :)
Edit:
Navigation in WP7 works very similar as the standard navigation in Silverlight 4, but it's a bit more restrictive. Just throw a PhoneApplicationFrame in your XAML like this:
<phone:PhoneApplicationFrame x:Name="Frame" />
This is basically the same as a Silverlight frame. All the pages you create inherit from PhoneApplicationPage by default, so they can be showed in a frame without any changes.
Your whole application actually runs on a PhoneApplicationFrame. If you take a look at your App class you will see this:
public PhoneApplicationFrame RootFrame { get; private set; }
Here's the MSDN documentation for the navigation system on WP7
How i can attach a single close button on the tabcontrol in C#.
There is a many way to attach a close button individually on each tabpages but I want to attach only single(e.g.) we can see on microsoft visual stdio 2008.
So Plz help me.
Here is a cheap way to do it, which might get you started:
<Window x:Class="WpfApplication1.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="MainWindow" Height="350" Width="525">
<DockPanel>
<TabControl DockPanel.Dock="Top">
<TabItem Header="Test1" />
<TabItem Header="Test2" />
<TabItem Header="Test3" />
<TabItem Focusable="False">
<TabItem.Header>
<Button Command="{Binding CloseTab}" Content="X" Width="21" HorizontalAlignment="Stretch" />
</TabItem.Header>
</TabItem>
</TabControl>
</DockPanel>
</Window>
You then are left to implement a public ICommand CloseTab field or property on your DataContext, and style the tab control to your liking.
Edit:
If you use this method:
Wiring up the button is tricky. You have to be careful not to close the tab that contains the button
This isn't well adapted to dynamically created tabs, because you have to ensure the close button is appended to the list
You have to figure out how to re-select the last selected tab, when you close the selected tab
You'll also have weird behavior when tabs start to wrap
The tab-stop behavior is hard to get right. You can't make the last TabItem focusable, since focus is used to determine what to close, but tabbing to the close button breaks the normal TabItem keyboard flow
I have come up with a style that makes the button look like a regular tab, with a bold X on it, which makes it visually more like IE8, and fixes the keyboard selection problem. But it is complicated, and this solution is complicated enough.
Ultimately, a close button on every tab jives better with the tab control's default behavior. The only problem with that solution is that it takes up more space. You could cheat and make the close button collapse until you mouse over the tab item, though that's sort of a user-experience no-no, unless you just shrink it.
If you are serious about following through with the separate close button, I suggest you look at this article, and adapt what they do for the scroll buttons to your close button:
http://www.blogs.intuidev.com/post/2010/02/10/TabControlStyling_PartThree.aspx
Ignore what they do for close buttons :)
Would it be possible to have your tabcontrol on another container control and let that control's close button do the job?