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Terrible performance of MapControl with multiple children in Windows Phone 8.1 Runtime

I have a MapControl which is supposed to be filled with multiple objects (500+). These objects represent some kind of POI. When the user taps on the object (pushpin) I display more info about the POI. So, I need:
A MapControl capable of handling high amount of child objects
Intercept Tappedevent of the child object
In order to achieve the second goal I decided to define my own pushpin template:
<maps:MapControl x:Name="Map">
<maps:MapItemsControl ItemsSource="{Binding Pushpins}">
<maps:MapItemsControl.ItemTemplate>
<DataTemplate>
<Image Width="40"
Height="40"
Source="{ ... }"
Tapped="OnPushpinTappedAsync"
maps:MapControl.Location="{Binding Location}"
maps:MapControl.NormalizedAnchorPoint="{Binding AnchorPoint}" />
</DataTemplate>
</maps:MapItemsControl.ItemTemplate>
</maps:MapItemsControl>
</maps:MapControl>
This works great except for the fact that.. the visual out of such approach is AWFULL. Every time I move a map, every Pushpin flickers a lot. It's like they are not, I don't know, bound to the position. They are also lagging. It looks really bad. Rendering of those objects is really poor.
The alternative is to add elements to the MapControl's MapElements property. It makes rendering of those objects really nice.
But then I loose binding ability and will have to workaround it - I'm not a big fan of that. There's also a second problem - from what I've read, rendering objects of the MapElements collection is a best effort deal. So it does not guarantee that it will succeed. And that is not an option for me, as in the future I plan to add clustering functionality, so I need to have a full control over what is being rendered on the map and what is not.
Do you have any idea why these MapControl's elements flickers so much? What can I do to prevent it? Thanks in advance for any hint or answer.

I'm facing the exact same problem. Seems to me, that the MapControl is completely broken. There are many more bugs besides performance :(
You cannot really solve the problem, but you can create a "oldschool" WP8.0 Silverlight application and use something like this:
<Page xmlns:map="clr-namespace:Microsoft.Phone.Maps.Controls;assembly=Microsoft.Phone.Maps">
<map:Map Grid.Row="1" x:Name="myMap">
<tool:MapExtensions.Children>
<tool:MapItemsControl>
... and so on ...
This performs great but of course you have to change everything from Win(P)RT to Silverlight...

I too faced this problem, but I find this library to be usefull.
Hopefully Microsoft updates the MapControl for Windows 10.

Try this:
Tag="{Binding index_of_collection}"
and this:
OnPushpinTappedAsync()
int index = (int)(sender as Image).Tag; //index_of_collection

WP8 - C# - Getting object value from Telerik RadPickerBox

I am currently having an issue regarding this component.
This is the xaml usage of it in my app:
<telerikPrimitives:RadPickerBox x:Name="box_change" Width="0">
<StackPanel Background="White">
<StackPanel Height="618">
<PasswordBox Name="NewPassword1" Padding="2,8,2,8" Margin="10,0,10,0" Style="{StaticResource PasswordBoxStyle}" />
</StackPanel>
</StackPanel>
</telerikPrimitives:RadPickerBox>
I am currently in need of retrieving, from my C# code, the value "password" of the field "NewPassword1", still I am unable to do that.
I already tried retrieving it with something like this:
box_change.NewPassword1.Password
but, of course, else I wouldn't be asking this question right now, this way doesn't work.
What would you suggest to retrieve the value?
Thanks in advance,
Guido

this.NewPassword1.Password
Glad to help!

Have you considered using Telerik's RadPasswordBox for WP8? It's optimized for passwords with masking characters and other features (and easily provides you with the password):
var userEnteredPassword = myPasswordBox.Password;
That being said, even though your PasswordBox is the child of two StackPanels, you can access the Password box in the same scope via NewPassword1. If you have more complex controls see the control's documentation on how to get the value of a child element.

Localize text that is already data binding? WP8

I have a Longlistselector that is getting the text through data binding. My problem is I need it to be localized so it displays the right language, how is the right way to do it?
I tried the first way that came to my head, but I thought it doesn't work:
MainPage.cs
_UserAdBL.Add(new UserAdB("{Binding LocalizedResources.UsText01, Source={StaticResource LocalizedStrings}}"));
Any help will be appreciated, thanks!

If I understand you correctly, you want to get the value of the {Binding LocalizedResources.UsText01, Source={StaticResource LocalizedStrings}} XAML binding in C#.
So use AppResources.UsText01 like so
_UserAdBL.Add(new UserAdB(AppResources.UsText01));

Data binding the Text property of a Run

I'm trying to databind a Run of a TextBlock in code at runtime, and I can't for the life of me figure out how.
Several sources on the internet suggest this isn't possible without some (not too pretty) additional workarounds, and, more importantly, it should completely fail when you try to do it in XAML.
Yet, in my application I have the following, which works beautifully:
<DataTemplate x:Key="PitchTemplate">
<Grid Width="120" Height="120" HorizontalAlignment="Center" VerticalAlignment="Center">
<TextBlock HorizontalAlignment="Center"
VerticalAlignment="Center"
TextAlignment="Center">
<Run Text="{Binding}" FontFamily="{StaticResource PhoneFontFamilySemiBold}" FontSize="36"/>
<LineBreak/>
<Run Text="{Binding Frequency, StringFormat=\{0:n2\}Hz}" FontFamily="{StaticResource PhoneFontFamilyNormal}" Foreground="{StaticResource PhoneSubtleBrush}"/>
</TextBlock>
</Grid>
</DataTemplate>
So I figured: If it can be done in XAML, it should be possible to do it in code.
Sofar, to no avail. Using the "regular" way of binding in code won't work; the Run class doesn't inherit from FrameworkElement, so doesn't have a SetBinding method, and it's Text property is not a DependencyProperty.
Using BindingOperations.SetBinding doesn't work because the Text property is not a DependencyProperty.
I'm up to the point that I'm willing to accept that it can't be done at runtime (although not without a last attempt at StackOverflow), but I'm still curious if
This can be done in code at runtime?
And if not:
How come it does work in XAML?
EDIT:
The example shown is just there to show that it can be done in XAML. The reason I need to create the bindings in code, is that I have a control that dynamically creates other elements, which need to be data bound.
UPDATE:
As Pete and I both found out, there is a dependency property for Text, but it's private. I assume that's why it does work through XAML (the xaml parser probably has more rights when it comes to reflection, and more knowledge in general about classes).
The upside is, that this means (tried & tested) it also works through XamlReader.Load(), which is (sofar) the cleanest solution I've come up with.
But if anyone has anything better, I'd be glad to hear about it.

Run.Text is backed by the private TextProperty which means you can't directly set its value without some reflection gimmicks, something like this:
Run r=new Run();
r.Text = "Moo";
var field=r.GetType().GetField("TextProperty", BindingFlags.Static | BindingFlags.NonPublic);
var dp=field.GetValue(null) as DependencyProperty;
BindingOperations.SetBinding(r, dp, new Binding {...});
This is rather ugly, but perhaps it can be useful.
You can find various workarounds for this. This SO post uses a custom attached property to configure binding. The attached property is used because Run is a sealed class in Silverlight so you can't create you own Run that supports binding.

The reason that it works in XAML but not in code-behind might be that there is a dependency property for Text, but it is private. It's a little bit 'black magic' to me though, so that's just a guess! This is a strange one, as in WPF the Run does inherit from FrameworkContentElement and has a SetBinding method...
Could you create a subclass of Run that contains a public DependencyProperty for text? I'm afraid I don't have the Silverlight dev tools to hand to try it out at the moment, but I'll try and take a look later.

Thanks both to Pete & Panagiotis for their efforts and suggestions (both 1 up).
In the end, I decided to go with my own solution (found in the "Update" section of the question): Create dedicated XAML strings containing the Run including the binding, and use XamlReader.Load() to parse it, and return a Run object.
The situation I'm working on is quite specific, so a local solution to the problem is good enough (for now). Reflection, as suggested by Panagiotis, won't work due to restrictions imposed by Silverlight. Lastly, the BindableRuns solutions would need either extensive work to deal with nested properties, or I would have to "uglify" my view model, so I discarded it (also for now).
Thanks all for your input.

Can I implement ScrollToHorizontalOffset() functionality in XAML? (for a dynamic list)

Here's the problem: I have a data-bound list of items, basically a way for users to map a request to a response. The response is an xml-based file. I'm letting them queue these up, so I've used a combobox for responses. The responses will include the full path, so they get a bit long. I want the displayed text of the combobox to be right-justified so the user can see the file name. For my static controls, I just use ScrollToHorizontalOffset() when a file is loaded and I'm done. For this dynamic list, I'd like to do it in xaml.
The "somewhat ugly" solution would be to store all the ComboBox objects as they load... then I can call ScrollToHorizontalOffset() directly, but I'd really prefer to do it a cleaner way than that! EDIT: (Actually, this may not be reasonable. A quick look at trying to hack around this issue gets into some really awkward situations trying to map my datasource items to the controls)
I've tried HorizontalContentAlignment, that only impacts the "dropped-down" portion of the ComboBox.
I've also tried to hook other various loading events, but haven't found one that works.

Using an Item template you can decide what will be shown.
You can set tooltip. You can then also use converters to add the dots.
<ComboBox x:Name="ConfigurationComboBox" VerticalContentAlignment="Center" ToolTip="saved configuration" SelectionChanged="ConfigurationComboBox_SelectionChanged">
<ComboBox.ItemTemplate>
<DataTemplate >
<StackPanel>
<TextBlock Text="{Binding}" ToolTip="{Binding Path}"></TextBlock>
</StackPanel>
</DataTemplate>
</ComboBox.ItemTemplate>
</ComboBox>
To measure the text, see Measuring text in WPF.