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Load WPF UserControl with user input

I am still new to WPF so excuse this simple question.
But I just don't know how to load a UserControl in WPF where the user entered data.
The following scenario:
User enters data into the view and clicks Next. If he now clicks the Back button on the view, how can I display the entered data again?

As the fastest option is using property "Visibility" with onPropertyChaged.
You can create property
private Visibility m_controlUserVisibility = Visibility.Hidden;
public Visibility ControlUserVisibility
{
get { return m_controlUserVisibility; }
set
{
m_controlUserVisibility = value;
OnPropertyChanged();
}
}
and Binding in XAML
<UserControl Visibility="{Binding ControlUserVisibility}"></UserControl>
When you want show UserControl - write:
ControlUserVisibility = Visibility.Visible;

Assuming that your requirement is some form of multi-page wizard control ...
Create a set ViewModel classes, one for each page of the wizard, and set an instance of each as properties of your main ViewModel. Add a SelectedPage property and set to the initial page ViewModel. The forward / backward navigation between pages should update the SelectedPage value as appropriate. The entered data will stay in memory and will remain available as the user navigates between pages.
In the View, add a ContentControl and bind its Content property to SelectedPage, along with buttons to control the navigation between pages. Create a DataTemplate for each page ViewModel type in the ContentControl's resources, to define the UI layout for that page.

How to reload page when navigating

I am developing WPF MUI application.I navigate to another page using button onclick and print some text on page1.xaml . after i navigate using another button to print another text on page1.xaml .but i could not do that.my out put was not new text.it is early details only.can't reload page1.xaml .when navigating I pass the parameter and according to parameter print deference text on same page.can anyone help me?
this is my navigation code
var frame = NavigationHelper.FindFrame(null, this);
frame.Source = new Uri("../Content/Sale/SaleInvoice/Nested/saleNested.xaml", UriKind.Relative);

Have the page databound to a ViewModel. Once you want to refresh just create a new Viewmodel. It would make sense to have the execution of the reloading being done in a backgroudworker so your UI stays responsive. This is esspecially usefull if you are refreshing some resource from a webService or some other online source.

The Data bind to the page at the initial time to reload the page I'm using this method
On xaml page just add Loaded Property:
<UserControl x:Class="ModernUINavigationApp1.Pages.Page"
...
Loaded="OnLoad" >
Then Add event handler in code behind to make the page do whatever you want when it's loaded
private void OnLoad(object sender, RoutedEventArgs e)
{
}
Hope this help :D

Make sure your ViewModel implements INotifyPropertyChanged. If your Page1.xaml's DataContext is set to the ViewModel, and your XAML uses bindings properly, any change to the ViewModel will be reflected in the UI. You won't need to refresh anything. Just update the property in the ViewModel object.
If you update your question with example XAML and C#, I can be of more help.

LongListSelector: Item tap?

I am using LongListSelector control on Windows Phone 8 and can't figure out the best way to handle a tap on an item.
The few examples I've found rely on the SelectionChanged event. However, this solution is buggy because if I tap an item that opens a new page, hit back, and then tap the same item again, it won't work because this item is already selected, so SelectionChanged is not triggered.
I tried to register to the tap event and use the current selected item as the tapped one, but some times the current selected item is not the one I expect.
I could wrap my ItemTemplate in a button and handle the tap for each item but I need to reskin the button to make it look like a simple list item.
Finally, I don't understand why it is so complicated to achieve such a basic thing. Is there a simple and standard way I missed?
My second wish is to get an effect on the item when it is tapped. Is there any standard way to do it?

You could null your LongListSelector's SelectedItem at the end of each SelectionChanged event. I.e.
<phone:LongListSelector x:Name="LLS" SelectionChanged="LLS_SelectionChanged">
And the event handler:
private void LLS_SelectionChanged(object sender, SelectionChangedEventArgs e) {
// If selected item is null, do nothing
if (LLS.SelectedItem == null)
return;
// Navigate to the next page
NavigationService.Navigate(new Uri("/nextpage.xaml", UriKind.Relative));
// Reset selected item to null
LLS.SelectedItem = null;
}
You'll fire the SelectionChanged event twice, but nothing's going to happen the second time round and you should get the behaviour that you're looking for - (i.e Setting SelectedItem to null will trigger a new SelectionChanged event, but this second event gets caught in the if-statement)
As for the second part of your question, you might be better posting a new question.

I done it with the Tap event handling.
I prefer not to use Selected property, but get tapped item this way (and I haven't noticed any bugs):
MyListItemClass item = ((FrameworkElement)e.OriginalSource).DataContext
as MyListItemClass;
Also, you could get the original item ContentPresenter simple by navigating up through VisualTree from e.OriginalSource. That way:
ContentPresenter itemPresenter = SomeHelperClass
.FindParent<ContentPresenter>(e.OriginalSource,"");
Where FindParent is similar to find child in this question: How can I find WPF controls by name or type?
ContentPresenter is that object what you need to manually change the item template if you want to (to set "selected" state for example).

private void Item_tap(object sender, RoutedEventArgs e)
{
var element = (FrameworkElement)sender;
DataSource data = (DataSource)element.DataContext;
}

My second wish is to get an effect on the item when it is tapped. Is
there any standard way to do it?
For this the only thing you need to do add this to your control (or stackpanel where you want to have this effect):
<StackPanel toolkit:TiltEffect.IsTiltEnabled="True">

first add this to *.xaml page inside the
LongListSelectorSelectionChanged="listBox_SelectionChanged"
so that it looks like this :
<toolkit:LongListSelector x:Name="listBox" SelectionChanged="listBox_SelectionChanged">
then in the *.xaml.cs file in the event handler
private void listBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
{
// Write your logic on what you want to do with the selected item
}

In addition to halil´s answer:
First of all you need to install the Windows Phone Toolkit (WPtoolkit) by NuGet.
Than add the namespace declaration on the PhoneApplicationPage.
xmlns:toolkit="clr-namespace:Microsoft.Phone.Controls;assembly=Microsoft.Phone.Controls.Toolkit"
After this you can add toolkit:TiltEffect.IsTiltEnabled="True" to the control definition.
It is nice documneted by NOKIA:
http://developer.nokia.com/community/wiki/Tilt_Effect_for_Windows_Phone
Oliver

AutoCompleteComboBox Arrow Up/Arrow Down keys to scroll list

I created a simple AutoCompleteBox in my WPF app and it loads great with code intercepting the Populate event, but when the list pops up and I hit the arrow down key and get to the end of the list the vertical scroll bar doesn't scroll.
The values keep changing in the field like it is scrolling through them, but the scroll bar doesn't move.
If I use the mouse it scrolls fine.
I just need the arrow key to scroll it.
Any ideas/suggestions?
I am new to WPF and have searched forever for this fix.

Attach a SelectionChanged event and then, inside the handler:
private void AutoCompleteBox_OnSelectionChanged(object sender, SelectionChangedEventArgs e)
{
AutoCompleteBox box = (AutoCompleteBox)sender;
ListBox innerListBox = (ListBox) box.Template.FindName("Selector", box);
innerListBox.ScrollIntoView(innerListBox.SelectedItem);
}

I see the same behavior. I found a post on codeplex talking about a different issue but at the bottom of the post they have a class AutoCompleteBoxEx that supports ScrollIntoView, so you can hook up the SelectionChanged even and this should get you the behavior you want. I have no idea why this is not baked in. I have had a chance to test out the posted code.
Update
Just pasted the code from the post into a class and used it in the XAML by changing AutoCompleteBox to AutoCompleteBoxEx and adding namespace for AutoCompleteBoxEx and it worked fine. You don't have to specify any event in the XAML, nor do you need to add any code to the code behind.

WPF: adding a usercontrol to a window

First off, I'm new to WPF and C# so maybe the issue I have is really easy to fix. But I'm kinda stuck at the moment.
Let me explain my problem.
I have a WPF Window and two usercontrols (Controls and ContentDisplayer).
The usercontrol Controls, wich contains some buttons, is added in the XAML of the Window.
Nothing special here.
Window.XAML
<nv:Controls/>
Now, what I want to do is when a user is pressing a button in Controls, ContentDisplayer needs to be added to the Scatterview I have in my Window.
I solved the problem by adding the buttons to the Window, and not using the usercontrol Controls. But this is not what I want.
Window.XAML.CS
private static void Button_ContactChanged(object sender, ContactEventArgs e)
{
object ob = Application.LoadComponent(new Uri(
"NVApril;component\\XAML\\ContentDisplayer.xaml",
System.UriKind.RelativeOrAbsolute));
//Set a unique name to the UserControl
string name = String.Format("userControl{0}",
SurfaceWindow1_Scatterview.Items.Count);
UserControl userControl = ob as UserControl;
userControl.Name = name;
//Add the new control to the Scatterview
SurfaceWindow1_Scatterview.Items.Add(userControl);
SurfaceWindow1_Scatterview.RegisterName(name, userControl);
}
So the real question is: How do I add a usercontrol to the Window by pressing a button in an other usercontrol?
Thanks,
Toner

At the top of the window xaml add
xmlns:d="clr-namespace:SomeNamespace.Usercontrols"
where you these exist already, you can choose the namespace of your control from the intellesence list.
Then where you want to place the control type:
<d:yourusercontrolhere params />
and your usercontrols can be added there.

Within Controls expose an event that is fired when you want to add a new control.
public event EventHandler AddControl;
private void RaiseAddControl()
{
if (AddControl!= null)
{
AddControl(this, EventArgs.Empty);
}
}
Now sink that event in your Window
yourControl.AddControl += ContactChanged

In your window, it sounds like you need to add the event to the instances of Controls.
<local:ContentDisplayer>
...
<nv:Controls AddControl="ContactChanged"/>
...
Then in your ContactChanged event handler you can instantiate a new Controls control and add it to whatever collection you're using like in your Button_ContactChanged event handler above.
Let me know if you need further clarification.

I have no idea what you are trying to do your example,
So you have a control defined thus:
public partial class somecontrolname : UserControl
With your corresponding Xaml file
All you need to do to add it in code to your window is firstly you need a LayoutRoot such as Grid control in the window then just
[mylayoutcontrol].Children.Add(new somecontrolname());
Maybe I got wrong idea what you are trying to do, your example code doesn't make much sense to me, looks like you are trying to load the xaml source file