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How to get control of the Headers in the Pivot.HeaderTemplate?

I have a pivot with a Header template, I want to access the headers from c# and then do some manipulations on them.
But unfortunately I can't get direct access to them.
Code :
<Pivot x:Name="mainContentPivot" Grid.Row="1"
ItemContainerStyle="{StaticResource CategoriesPivotItemsStyle}"
>
<Pivot.HeaderTemplate>
<DataTemplate>
<StackPanel>
<TextBlock Text="{Binding TitleHeaders}" FontSize="16" />
</StackPanel>
</DataTemplate>
</Pivot.HeaderTemplate>
</Pivot>
How do I access the individual Header's that are created after the Pivot is bound to an itemsSource?
Edit: My main aim here I wanted to override the Pivot arrows to act as paging since I have a lot of PivotItems more than that can be displayed on the screen at once. Hence when a user taps on the next pivot arrow I would like to skip all the PivotItems which are visible and go to next PivotItem which can't be seen in the view.
In order to do this I thought I need to calculate the size of the header's (since different headers are of different sizes) and then with the help of this I would get to know how many PivotItem's are current shown in the view and based on which I can select the next PivotItem.

XAML SampleData Binding to Values of a List of Strings

OK, so I've searched and searched and searched, and I can't find an answer to this specific angle of my question. I know how to bind to a List, and how to make it auto-updating by making it an ObservableCollection instead of a List. However, with just a list of Strings, how the heck to I bind to the value of each List element?
<DataTemplate x:Key="PageTiles">
<Grid Background="{StaticResource PhoneAccentBrush}"
Margin="6,0,6,12">
<StackPanel VerticalAlignment="Bottom">
<TextBlock Text="{Binding}"
Margin="6,0,0,6" />
</StackPanel>
</Grid>
</DataTemplate>
Here's the LongListSelector that pulls from the list:
<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0" VerticalAlignment="Top" Height="60">
<phone:LongListSelector Margin="0,0,-12,0"
ItemsSource="{Binding PageTitles}"
LayoutMode="Grid"
GridCellSize="150,150"
ItemTemplate="{StaticResource PageTiles}"
SelectionChanged="LongListSelector_SelectionChanged">
</phone:LongListSelector>
</Grid>
Now, I've used a similar layout before to do tiles based off a List of classes that have string properties, but never with a List of strings, and I can't find anything to guide me in the right direction.

So it turns out #har07 was right. The Text="{Binding}" I'd put in the text value was valid, my cell size was just too large for it to show in the 60 high grid that I'd made. Reduced the height of it to less than the stack panel's height and bam, there it was. I didn't even do that on purpose, that's just how I'd left it while I didn't know what to put in there, and because I hadn't recompiled to get the associations fixed, it wasn't finding anything to put in as elements.
So, to recap, to get the values of a List directly instead of something that's part of that value, a simple "{Binding}" does the trick. Lesson learned: double check your size values before running for help XD.

Windows 8 XAML/C# - How to draw dynamic elements on a canvas?

I have canvas control I'm using for a graph and need to be able to dynamically add a variable amount of data points to it. Maybe I'm not aware of a good control to do this type of thing with but I was trying to do it with a GridView as such:
<Canvas x:Name="GraphPointsAndLines" Canvas.ZIndex="2">
<GridView x:Name="gvDataPoints">
<GridView.ItemTemplate>
<DataTemplate>
<Button IsEnabled="False" Canvas.Left="{Binding PointXValue}" Canvas.Top="{Binding PointYValue}" Content="{Binding Value}" Style="{StaticResource ButtonGraphPoint}" />
</DataTemplate>
</GridView.ItemTemplate>
</GridView>
</Canvas>
But due to the nature of the gridview it's not recognizing that the child button elements are a part of any such canvas and just ends up stacking them on top of one another. Can anyone offer any suggestions?

This could be interesting: simple technique for databinding to position.
Basically, have an items control with an items source and apply the data template, set its items panel and apply the items container style.

Empty LongListSelector causes infinite ScrollViewer

This is the situation:
I have a datasource that gets filtered by certain attribute (lets call it Checked), into two lists on the viewmodel. Call it New and Old.
New one needs to be displayed into one list, Old one needs to be displayed into the list right under it.
Oh and they need to scroll in unison. So if Old is currently out of screen, it will swim into visibility as the list is swiped up.
I've currently solved this with LongListSelectors like this:
<ScrollViewer VerticalAlignment="Top" VerticalScrollBarVisibility="Auto">
<StackPanel>
<phone:LongListSelector x:Name="NewList" Margin="0,0,0,0" ItemsSource="{Binding New}" SelectionChanged="NewList_SelectionChanged">
<phone:LongListSelector.ItemTemplate>
<DataTemplate>
<StackPanel Margin="0,0,0,17">
<TextBlock Text="{Binding Name}" TextWrapping="Wrap" Style="{StaticResource PhoneTextExtraLargeStyle}" Foreground="{Binding Color}" />
</StackPanel>
</DataTemplate>
</phone:LongListSelector.ItemTemplate>
</phone:LongListSelector>
<phone:LongListSelector x:Name="OldList" Margin="0,0,0,0" ItemsSource="{Binding Path=Old}" Padding="0,20,0,0">
<phone:LongListSelector.ItemTemplate>
<DataTemplate>
<StackPanel Margin="0,0,0,17">
<TextBlock Text="{Binding Name}" TextWrapping="Wrap" Style="{StaticResource PhoneTextExtraLargeStyle}" FontStyle="Italic" Foreground="{Binding Color}"/>
</StackPanel>
</DataTemplate>
</phone:LongListSelector.ItemTemplate>
</phone:LongListSelector>
</StackPanel>
</ScrollViewer>
Two longlistselectors inside a stackpanel inside a scrollviewer. Now it all works absolutely fab while there's something in both of those lists.
However, when one of them has no content whatsoever, it immediately expands to fill the entire height of its parent. In this case... the infinite scrollviewer. Which means that if there's nothing in the New list, there will be absolutely nothing visible on the screen whatsoever and if there's nothing on the New list... I can pretty much scroll infinitely after getting past the New list items.
Do I have any options here? Without programmatically creating a ton of Text fields and then trying to attach events to it, or worse, write my own list control? Standard listboxes don't work because they both scroll separately.
Any ideas?

Having two list controls under each other is a genrally a bad idea, because of ScrollViewers inside ScrolViewers.
I would advise you to use a single LongListSelector without any ScrollViewer around it.
Then create a single collection with old an new items and use an ItemTemplateSelector to style them differently.

The problem you are facing is that by the default when emty LLS is measured it's height as you see is 'infinite'. You are using StacPanel which means that second LLS is under infinite LLS.
The simples solution is to set the Height of LLS:
<phone:LongListSelector x:Name="NewList" Height="300" Margin="0,0,0,0" ItemsSource="{Binding New}" SelectionChanged="NewList_SelectionChanged">
If you can - use a Grid with defined rows instead of StacPanel. If you still want to use StackPanel, you can override the method MeasureOverride() in LLS and make extension.
It should work if you do it like this:
namespace Extensions
{
public class LongListSelectorEx : LongListSelector
{
protected override System.Windows.Size MeasureOverride(System.Windows.Size availableSize)
{
if (this.ItemsSource == null)
return new System.Windows.Size(this.Width, 0);
if (this.ItemsSource.Count <= 0)
return new System.Windows.Size(this.Width, 0);
return base.MeasureOverride(availableSize);
}
}
}
Watch out also if you haven't got width defined (the return value cannot be NaN - in that situation put 0 instead this.Width). Of course you will also need to check Height of LLS, bacause if you don't your controls can be pushed off the screen, when there are many items in LLS.
You can also read about this here

Get a textblock value in a listbox using GestureServices

Sorry guys, I had asked this question earlier but could not figure out the answer. Made an edit to see if that bumps it, but that did not seem to work. So here is the last try to the question
I can't seem to figure out how one can get the value of a specific textblock in a listbox. To start things off, here is the code:
<ListBox HorizontalAlignment="Left" Name="listItems" VerticalAlignment="Top" >
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" Height="210" >
<Grid Height="210" Background="#75FFF8DC">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener Tap="GestureListener_Tap"
DoubleTap="GestureListener_DoubleTap"
Hold="GestureListener_Hold"
Flick="GestureListener_Flick"/>
</toolkit:GestureService.GestureListener>
...CODE...
</></></>...
The code area contains a bunch of other grids, partitions (columns and rows) and textblocks. Here is an example:
<Image Name="XXX" Source="{Binding XXXPath}" Stretch="Fill"
Grid.Column="0"/>
<TextBlock Name="YYY" Grid.Column="1" Grid.Row="0"
Text="{Binding YYYPath}" Foreground="Black"/>
<TextBlock Name="ZZZ" Grid.Column="2" Grid.Row="0"
Text="{Binding ZZZPath}" Foreground="Black"/>
So what I want, is if someone taps the grid (that means anything in the grid, including these textblocks and images), I want to first get the text of the textblock "YYY."
I could have inserted that code into a textblock and used sender as textblock, but I do not want to limit my gestures to one textblock, nor do I want to repeat that for each element in the grid (lots of issues and seems unnecessary).
Edit: If this does not work, I can also implement just one tap gesture (but again, for the whole grid) and use that to get the value of the textblock. Is there no way? Otherwise I will have to do this: Add tap for the textblock and use sender as a textblock, then get the value of the text. But I really do not want to use this approach.

I see you use bindings for your textblocks and image. So why don't you use ( if you haven't already done it) an IList instance of class which hold an information about them? Then set this instance as an ItemSource for your listbox. That way when user taps somewhere on listbox you can catch the SelectedIndex or SelectedItem of a listbox item. And this will help you to figure out which element of IList collection to extract so you could get your text or image or whatever you need.
And you don't need to use GestureServices from external Silverlight Toolkit with Mango. Tap, DoubleTap etc. are built-in.