Creating a Looping Listbox - windows-phone-7

Hi I want to create a looping listbox so that the last item's next item is the very first item and vice versa - creating a listbox that doesn't have a top or a bottom.
I know there is a LoopingSelector in the WP7 toolkit but it doesn't quite do what I want since it fades in/out peripheral items and you have a 'selected' item that is always in the middle.
I looked at the LinkedList collection but it doesn't seem to support looping: "The LinkedList(Of T) class does not support chaining, splitting, cycles, or other features that can leave the list in an inconsistent state."
Does anyone know a solution for what I'm looking for or would I need to develop a hybrid of the current Listbox and the toolkit's LoopingSelector?
Many thanx!

Take a look at Petzold's article on circular lists in MSDN Magazine.

I recently have a same problem as your! I use blend 4 to handle this, making my list reset to certain position at certain time, also adding a copy of a list in front and behind of the original list.
example: my list is: 1-2-3-4-5-6,
I would make it 1-2-3-4-5-6-1-2-3-4-5-6-1-2-3-4-5-6
and it reset to original position every 20sec. For example: if user was on item 4 it would reset the position to item 4 but at the middle list.
I currently have my question asking here you can check out if anything help:
horizontal listbox that could be infinite circle scrolling

Use Scrollviewer contains listbox, put manipulationCompleted event and use ScrolltoVerticalOffset(0) to have it looping scrolling. Maybe my code would help:
<ScrollViewer HorizontalScrollBarVisibility="Auto" Margin="-2,567,-1,0" x:Name="imagesScrollview"
Opacity="1" Grid.Row="1" RenderTransformOrigin="0.5,0.5"
ManipulationCompleted="imagesScrollview_ManipulationCompleted" Height="85" MouseLeftButtonDown="ScrollViewer_MouseLeftButtonDown">
<ScrollViewer.Background>
<ImageBrush ImageSource="/PhoneApp11;component/Images/top_friends_float.png" />
</ScrollViewer.Background>
<ListBox x:Name="listBox" ScrollViewer.HorizontalScrollBarVisibility="Disabled" ScrollViewer.VerticalScrollBarVisibility="Disabled" Width="Auto" Height="80" Background="{x:Null}">
<ListBox.ItemTemplate>
<DataTemplate>
and in Manipulation event:
private void imagesScrollview_ManipulationCompleted(object sender, ManipulationCompletedEventArgs e)
{
ScrollViewer scrollviewer = sender as ScrollViewer;
if (scrollviewer.HorizontalOffset > (listBox.ActualWidth - 700))
scrollviewer.ScrollToHorizontalOffset(0);
else if (scrollviewer.HorizontalOffset < 100)
scrollviewer.ScrollToHorizontalOffset((listBox.ActualWidth - 487));
}
***Notice: I allow my scrollviewer to loop in both way.

Related

Is there a way to capture scroll events on a List-View in NativeScript

I'm using a grid layout for a List View for a simple RSS reader, and want to reload the list if the user scrolls past the top (standard Android design pattern).
From the ui/gestures module I've tried the swipe and pan gestures, but I haven't been able to determine the scroll position from those. for example:
XML
<ListView pan="myFunc"items="{{ myItems }}">
<ListView.itemTemplate>
<GridLayout columns="*,3*" rows="*,2*">
...
</GridLayout>
</ListView.itemTemplate>
</ListView>
JS
function myFunc(args){
if(args.deltaY > 0 && args.deltaX > -10 && args.deltaX < 10){
console.log('swiping down');
}
}
invokes myFunc and I can determine deltaY, but I'm not sure how to find the vertical offset from it's args object to tell if the user is trying to scroll past the top.
I saw the ui/scroll-view module, but I don't know how that will interact with my GridLayout and ListView.
New to this project, and it feels like I'm overlooking something simple.
Would be grateful for any insight. Thanks!

Side scrolling menu with gesture removable items

I am trying to create a menu (currently a ListBox containing Images) for an app (WP8 specifically, but general principal will be the same for other environments) with the behavior determined by the initial part of each gesture:
dragging/swiping the menu left or right will cause the menu to scroll left or right
dragging an item up from the menu (which is at bottom of screen) will allow it to be detached (or recreated) and placed in another container.
Roughly speaking, I understand how to drag-and-drop the element, and to make a side-scrolling menu, but I am having difficulties in putting the two together and determining whether to be in "menu scroll" mode, or "drag and drop" mode, and how to switch between the two programmatically.
<ListBox Height="100"
ItemsSource="{Binding}"
ScrollViewer.HorizontalScrollBarVisibility="Auto"
ScrollViewer.VerticalScrollBarVisibility="Disabled"
Grid.Row="1"
Name="MainMenuPicker">
<ListBox.ItemsPanel>
<ItemsPanelTemplate>
<StackPanel Orientation="Horizontal">
</StackPanel>
</ItemsPanelTemplate>
</ListBox.ItemsPanel>
<ListBox.ItemTemplate>
<DataTemplate>
<Image Source="{Binding Path=Source}" Tap="Image_Tap"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Currently, horizontal scrolling is taken care of by ScrollViewer.HorizontalScrollBarVisibility="Auto"
I attempted to have a ManipluationStarted, ManipulationDelta etc to determine direction of gesture, but didn't get very far. I currently have a Tap event handler on the Image that moves moving to another parent container.
Questions:
1. How can I determine if a gesture is a side-to-side movement on the menu (ListBox) as a whole, or a drag (upwards) of an Image within the ListBox?
How can I programmatically set each case so that the functionality behaves as described?
Thanks in advance!
In this case you need to use Flick events,and use HorizaltalVelocity and vertcalvelocity to detect and distinguish between left-right and top-down swipes.
check this sample for better understanding

How to make a scrollviewer gain focus when selected

I have a project where I have multiple scrollviews in one:
I can scroll up and down through a single item, and also through multiple items horizontally.
Normally, the webview is not hittestvisible.
Moving horizontally works fine, but when I scroll down, I give focus and hittestvisibility to the single item, but it won't scroll down. Only when I scroll down the second time, it will scroll, I think because when the ManipulationStartedevent was fired, it was caught by the scrollview, which had focus at the time, and only later the webview takes the focus, therefore, it has no started position. Is there a workaround for this problem?
<ScrollViewer x:Name="Scroller"
HorizontalScrollBarVisibility="Auto"
VerticalScrollBarVisibility="Disabled"
ManipulationMode="Control"
Grid.Row="1" Grid.RowSpan="2" >
<StackPanel Name="WebScrollView" Orientation="Horizontal" >
<UserControl Name="LeftContentControl" MinWidth="480" />
<UserControl Name="MiddleContentControl" MinWidth="480" />
<UserControl Name="RightContentControl" MinWidth="480" />
</StackPanel>
</ScrollViewer>
So, Left, Middle and Right are the three controls which will hold the webviews as their content. When scrolled to the left( for example ), the left content is placed over the middle content, and the middle content is set into view again, so it seems like an endless list of webviews, but really are three.
I use a mediator to achieve the animation of the webviews.
Thanks in advance.
GeekPeek

Bing map rotation in windows phone pivot

I have a trouble when try to rotate MapBase. As far as I didn't find a way to rotate content inside map(i mean tiles). I made a rotation transform with map itself and put it in square to emulate a rectangual viewport.
The problem is the map corner flows over corner of square while rotating and what worst it moves over pivot items titles and I don't know how to bring it to the bottom.
Is there any workaround of that? Or may be other way to rotate the map content?
UPDATE
XAML CODE
here is my code
<Grid x:Name="LayoutRoot" Background="Transparent">
<!--Pivot Control-->
<controls:Pivot Title="MY APPLICATION">
<!--Pivot item one-->
<controls:PivotItem Header="first">
<Grid d:LayoutOverrides="Height" Margin="-44,-30,44,30">
<Microsoft_Phone_Controls_Maps:Map Margin="-18,-72,2,76" RenderTransformOrigin="0.5,0.5" UseLayoutRounding="False" d:LayoutRounding="Auto">
<Microsoft_Phone_Controls_Maps:Map.RenderTransform>
<CompositeTransform Rotation="36.01"/>
</Microsoft_Phone_Controls_Maps:Map.RenderTransform>
</Microsoft_Phone_Controls_Maps:Map>
<Rectangle Fill="#FFF4F4F5" Height="54" Margin="-14,-42,0,0" Stroke="Black" VerticalAlignment="Top"/>
</Grid>
</controls:PivotItem>
<!--Pivot item two-->
<controls:PivotItem Header="second">
</controls:PivotItem>
</controls:Pivot>
</Grid>
In the example is on the top of map, but map is on the top of Pivot headers and even application title is on the back of map corner...
And If you Load another page in "Paysage Orientation" when you rotate your phone ? (It's maybe a temporaly solution... ) but you want to reaload your map with good dimension.
It's not a good idea to use a Map Control inside a Pivot if gesture interaction is enabled.
Don’t use Slider, ToggleButton, or Map controls in a Pivot control. Don’t use controls that can pan or scroll inside a Pivot control. For example, if you put a Map control inside a Pivot control it might be difficult to use the Pivot control. The gesture input gets confused. The solution is to navigate to a subpage with controls that require gesture input. You can place a map in a pivot page as long as the map isn’t enabled for gesture interaction. You could overlay a button that would activate the map. Pressing the button would actually navigate to a separate page with just the Map control on it. The user could then press the Back button to go back to the Pivot control.
http://msdn.microsoft.com/en-us/library/windowsphone/design/hh202919%28v=vs.105%29.aspx

Windows Phone ListBox: how to scroll it?

I've got a ListBox (dynamically populated via code):
(i can't insert the code, bah)
I need, with a button, to move this listbox vertically. The listbox have a fixed height, and also the items.
Can someone help me?
Per MSDN, it looks like this is a viable answer for you?
ListBox.ScrollIntoView Method
Edit - Comment Summary of Answer: The question here was targetting scrolling itself, not to a particular object. As such, the necessary action was to attain a reference to the ListBox's ScrollViewer. From there, a call needed to be placed to the ScrollViewer's ScrollToVerticalOffset method. As the OP wanted to scroll down a certain amount from the original position, the ScrollViewer's VerticalOffset property was incorporated into the call.
This works. Set the ListBox to not scroll, then add a ScrollViewer around it. Now in your code behind you can set the ScrollViewer to whatever you want.
XAML:
<!--Disable the ListBox scroll and add a ScrollViewer so we have control over the scroll position.-->
<ScrollViewer
Name="scrlvwrListBoxMessages"
VerticalScrollBarVisibility="Auto" >
<ListBox x:Name="lstbxMessages"
ScrollViewer.VerticalScrollBarVisibility="Disabled" >
</ListBox>
</ScrollViewer>
Code:
private void ScrollToBottom()
{
//Scroll to the bottom.
Dispatcher.BeginInvoke(() =>
{
this.scrlvwrListBoxMessages.ScrollToVerticalOffset(double.MaxValue);
});
}

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