Implementing Drag and Swapping items in windows Phone - winforms

Question

I am new to windows phone.My problem is the following:
I have a grid of items which are buttons. I want to implement drag and swap feature for the buttons.How to do this in WP7 platform.

Answer 1

Here is the solution! xaml looks like this
<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">
<toolkit:WrapPanel Height="510" HorizontalAlignment="Left" Margin="18,56,0,0" Name="wrapPanel1" VerticalAlignment="Top" Width="411">
<Button Content="1" Height="124" Name="button2" Width="134">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
<Button Content="2" Height="124" Name="button3" Width="134" >
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
<Button Content="3" Height="124" Name="button4" Width="134">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
<Button Content="4" Height="124" Name="button5" Width="134">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
<Button Content="5" Height="124" Name="button6" Width="134">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
<Button Content="6" Height="124" Name="button7" Width="134">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
<Button Content="7" Height="124" Name="button8" Width="134">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
<Button Content="8" Height="124" Name="button9" Width="134">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
<Button Content="9" Height="124" Name="button10" Width="134">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
<Button Content="10" Height="124" Name="button11" MouseLeftButtonDown="mouseDown" Width="134">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
<Button Content="11" Height="124" Name="button12" Width="134">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
<Button Content="12" Height="124" Name="button13" Width="134">
<toolkit:GestureService.GestureListener>
<toolkit:GestureListener DragDelta="GestureListener_DragDelta" DragStarted="GestureListener_DragStarted" DragCompleted="GestureListener_DragCompleted" />
</toolkit:GestureService.GestureListener>
</Button>
</toolkit:WrapPanel>
</Grid>
Now the code behind C#
TranslateTransform translateTransform;
PointCollection points = new System.Windows.Media.PointCollection();
Button firstObject;
private void GestureListener_DragStarted(object sender, DragStartedGestureEventArgs e)
{
translateTransform = new TranslateTransform();
firstObject = sender as Button;
var transform1 = firstObject.TransformToVisual(wrapPanel1);
Point absolutePosition1 = transform1.Transform(new Point(0, 0));
}
private void GestureListener_DragDelta(object sender, DragDeltaGestureEventArgs e)
{
var moveablebutton = sender as Button;
moveablebutton.RenderTransform = translateTransform;
translateTransform.X += e.HorizontalChange;
translateTransform.Y += e.VerticalChange;
}
private void GestureListener_DragCompleted(object sender, DragCompletedGestureEventArgs e)
{
var lastObject = sender as Button;
Button b=new Button();
int count = wrapPanel1.Children.Count;
int index = wrapPanel1.Children.IndexOf(lastObject);
var transform2 = lastObject.TransformToVisual(wrapPanel1);
Point absolutePositon2 = transform2.Transform(new Point(0, 0));
Point P1;
Point P2 ;
Point P3 ;
Point P4 ;
P1 = e.GetPosition(wrapPanel1);
P2 = new Point(P1.X+134, P1.Y+124);
Button swapitem=null;
foreach (UIElement ctrl in wrapPanel1.Children)
{
int index2;
var transform3 = ctrl.TransformToVisual(wrapPanel1);
Point comparePos = transform3.Transform(new Point(0, 0));
swapitem = ctrl as Button;
index2 = wrapPanel1.Children.IndexOf(swapitem);
if (index != index2)
{
P3 = new Point(comparePos.X, comparePos.Y);
P4 = new Point(comparePos.X + 158, comparePos.Y+170);
if (!(P2.Y < P3.Y || P1.Y > P4.Y || P2.X < P3.X || P1.X > P4.X))
{
swapitem = ctrl as Button;
index2 = wrapPanel1.Children.IndexOf(swapitem);
b = lastObject as Button;
b.RenderTransform = translateTransform;
translateTransform.X -= e.HorizontalChange;
translateTransform.Y -= e.VerticalChange;
wrapPanel1.Children.Remove(lastObject);
wrapPanel1.Children.Remove(swapitem);
// wrapPanel1.Children.RemoveAt(index2);
if (index < index2)
{
wrapPanel1.Children.Insert(index, swapitem);
wrapPanel1.Children.Insert(index2, b);
}
else
{
wrapPanel1.Children.Insert(index2, b);
wrapPanel1.Children.Insert(index, swapitem);
}
break;
}}
}
}