topic Re: Slide between layers in ArcGIS API for Silverlight Questions

Slide between layers

JayKappy — Fri, 04 Mar 2011 20:26:39 GMT

Looking for an example of a slide bar that moves from one layer to another...increases and decreases the transparency from one to the other....

Say from Streets to Aerials.....

THanks

Re: Slide between layers

JayKappy — Mon, 07 Mar 2011 12:57:59 GMT

I am a bit confused because I have a single one working on each layer in my layerlist....
I have a mixture of dynamic layers, graphic layers, wms layers etc....
I have two base layers (streets and Aerials)
I dotn want to put the streets and aerials layer list....I want to put them in the header with a slide bar that allows teh user to slide between the two increase and decreasing the opacity....
So At one side layer one will be seen...at the other end the other layer will be seen...in the middle they both will be seen....

Do I create another <esri:map and define the two layers that will be effected with the slider?
I cant see this as a solution because then I have another map that would have to be over the other one....

DO I have to change the Maximum on the Slider?
How do I point to 2 specific services, while continuing to draw the other layers and graphics...create another map service?

Anything to help me clarify this woudl be appreciated....

Re: Slide between layers

DominiqueBroux — Mon, 07 Mar 2011 13:20:49 GMT

Do I create another <esri:map and define the two layers that will be effected with the slider?

You can just add your 2 layers to the map and when the slider value changed (from 0.0 to 1.0), initialize the opacity of your first layer with the slider value and the opacity of your second layer with 1-value.

Re: Slide between layers

JayKappy — Sun, 12 Dec 2021 00:59:06 GMT

You can just add your 2 layers to the map and when the slider value changed (from 0.0 to 1.0), initialize the opacity of your first layer with the slider value and the opacity of your second layer with 1-value.

So I keep the original map and then create another one?

Or are you saying add to the same map...
THen in VB I change the opacity based on the slider value?

I can effect one layer like this....but looking to move between 2...and return the value of the Slider....I guess now I just need to grab that value and change the opacity on the two layers?????

But again in my example below I am pointing to a specific layer....I assume that I need to just point the MyMap .... and then in VB code change the opacity of the 2 layers????

Thanks

                <Slider x:Name="MySlider"
                VerticalAlignment="Top" 
                Minimum="0"
                Maximum="1"
                        Margin="0,40,0,0" MouseLeftButtonUp="GiveMeValue" 
               Value="{Binding ElementName=MyMap, Path=Layers[BaseLayerImage].Opacity, Mode=TwoWay}" />


    Private Sub GiveMeValue(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
        Dim Test As String = MySlider.Value
        MessageBox.Show(Test)
    End Sub

Re: Slide between layers

DominiqueBroux — Mon, 07 Mar 2011 13:57:52 GMT

Or are you saying add to the same map...

Yes, you don't need a second map to do that.

THen in VB I change the opacity based on the slider value?

Yes, easier by code (on event ValueChanged), else you would need a converter returning 1-value.

Re: Slide between layers

JayKappy — Sun, 12 Dec 2021 00:59:09 GMT

I did this and its workign....I can change to ValueChanged....just used MouseLeftButtonUp for testing....

1. Why do I need this? Path=Layers[BaseLayerImage].Opacity, mean its specifying a specific layer?

2. ONE LAST question....how would i do this with 3 layers?

                <Slider x:Name="MySlider"
                VerticalAlignment="Top" 
                Minimum="0"
                Maximum="1"
                        Margin="0,40,0,0" MouseLeftButtonUp="MultiLayerOpacity" 
               Value="{Binding ElementName=MyMap, Path=Layers[BaseLayerImage].Opacity, Mode=TwoWay}" />

    Private Sub MultiLayerOpacity(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
        Dim Test As String = MySlider.Value
        'MessageBox.Show(Test)

        Dim DynamicLayer1 As ArcGISDynamicMapServiceLayer = TryCast(MyMap.Layers("StreetMapLayer"), ArcGISDynamicMapServiceLayer)
        DynamicLayer1.Opacity = Test

        Dim DynamicLayer2 As ArcGISDynamicMapServiceLayer = TryCast(MyMap.Layers("BaseLayerImage"), ArcGISDynamicMapServiceLayer)
        DynamicLayer2.Opacity = 1 - Test

    End Sub

Re: Slide between layers

DominiqueBroux — Sun, 12 Dec 2021 00:59:11 GMT

1. Why do I need this? Path=Layers[BaseLayerImage].Opacity, mean its specifying a specific layer?

Since it's now done by code, you don't need to do it in xaml as well.

 
2. ONE LAST question....how would i do this with 3 layers?

It's depending on the logic you need (how one slider can manage 3 layers).
We can imagine to extent the maximum value to 2.0 and manage a smooth transition between layer1 and layer2 when the slider is between 0 and 1, and a smooth transition between layers 2 and 3 when the slider is between 1 and 2. There is no specific difficulties to do that by code.

Re: Slide between layers

JayKappy — Mon, 07 Mar 2011 14:49:25 GMT

..........................................................................

Re: Slide between layers

JayKappy — Sun, 12 Dec 2021 16:39:09 GMT

Yea I dont think this is workign right....I am going between StreetLayer and Aerials. I turn off Aerials and slide this slider and the StreetLayer does not change....I think its because I still have that line in the xaml file
If I remove the line in Red below it does not work. with it in there it only effects the opacity of which ever layer is specified.....what is wrong and why cant I remove it?

One last thing...in VB when I use the "MouseLeftButtonUp" I set these parameters....What parameters do I use if I am using a "ValueChanged"
MouseButtonEventArgs has to be changed to WHAT?

Private Sub MultiLayerOpacity(ByVal sender As Object, ByVal e As MouseButtonEventArgs)

Is my VB code completly wrong?
I cant even turn off the layer from within my VB....

Dim DynamicLayer2 As ArcGISDynamicMapServiceLayer = TryCast(Me.MyMap.Layers("Aerials"), ArcGISDynamicMapServiceLayer)
DynamicLayer2.Visible = False

                <Slider x:Name="MySlider" 
                        VerticalAlignment="Center" Minimum="0" Maximum="1" Width="50"
                        Margin="0,0,0,0" MouseLeftButtonUp="MultiLayerOpacity" 
                        Value="{Binding ElementName=MyMap, Path=Layers[Aerials].Opacity, Mode=TwoWay}" />

    Private Sub MultiLayerOpacity(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
        Dim Test As String = MySlider.Value

        Dim DynamicLayer1 As ArcGISDynamicMapServiceLayer = TryCast(MyMap.Layers("StreetMapLayer"), ArcGISDynamicMapServiceLayer)
        DynamicLayer1.Opacity = 1 - Test

        Dim DynamicLayer2 As ArcGISDynamicMapServiceLayer = TryCast(MyMap.Layers("Aerials"), ArcGISDynamicMapServiceLayer)
        DynamicLayer2.Opacity = Test

    End Sub

If I do this I get the messagebox value

    Private Sub MultiLayerOpacity(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
        Dim Test As String = MySlider.Value

        If Test > 0 Then
            MessageBox.Show("Yo")
            Dim DynamicLayer2 As ArcGISDynamicMapServiceLayer = TryCast(MyMap.Layers("Aerials"), ArcGISDynamicMapServiceLayer)
            DynamicLayer2.Opacity = Test
        End If
    End Sub

If I do this I dont....so somethign has to be wrong with the syntax or setting of the opacity

    Private Sub MultiLayerOpacity(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
        Dim Test As String = MySlider.Value

        If Test > 0 Then
            Dim DynamicLayer2 As ArcGISDynamicMapServiceLayer = TryCast(MyMap.Layers("Aerials"), ArcGISDynamicMapServiceLayer)
            DynamicLayer2.Opacity = Test
            MessageBox.Show("Yo")
        End If

    End Sub

Re: Slide between layers

JayKappy — Mon, 07 Mar 2011 20:48:25 GMT

I can get this to work with my map service...but tryign to use ESRIs and it wont work.....
Is it somethign to do with the ArcGISTiledMapServiceLayer??????????

These wont work for some reason....
<esri:ArcGISTiledMapServiceLayer ID="StreetMapLayer" Visible="True"
          Url="http://services.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer" />

And

<esri:ArcGISTiledMapServiceLayer ID="Aerials" Visible="True"
          Url="http://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer" />

Re: Slide between layers

DominiqueBroux — Sun, 12 Dec 2021 00:59:14 GMT

I can get this to work with my map service...but tryign to use ESRIs and it wont work.....

I can't figure out why it could be not working with ESRI services.

I tested this code and it works:

<esri:Map x:Name="MyMap" >
<esri:ArcGISTiledMapServiceLayer ID="StreetMap" Visible="True" 
           Url="http://services.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer" Opacity="1.0"/>
<esri:ArcGISTiledMapServiceLayer ID="Topo" Visible="True" 
           Url="http://services.arcgisonline.com/ArcGIS/rest/services/World_Topo_Map/MapServer" Opacity="0.0"/>
<esri:ArcGISTiledMapServiceLayer ID="Aerials" Visible="True" Opacity="0.0"
Url="http://services.arcgisonline.com/ArcGIS/rest/services/World_Imagery/MapServer" />
</esri:Map>
<Slider Height="23" HorizontalAlignment="Left" Margin="10,150,0,0" VerticalAlignment="Top" Width="100" Maximum="2" Minimum="0" ValueChanged="Slider_ValueChanged"/>
.........
 
private void Slider_ValueChanged(object sender, RoutedPropertyChangedEventArgs<double> e)
{
    var value = e.NewValue;
 
    if (value <= 1)
    {
        MyMap.Layers["StreetMap"].Opacity = 1.0 - value;
        MyMap.Layers["Topo"].Opacity = value;
        MyMap.Layers["Aerials"].Opacity = 0.0;
    }
    else
    {
        MyMap.Layers["StreetMap"].Opacity = 0.0;
        MyMap.Layers["Topo"].Opacity = 2 - value;
        MyMap.Layers["Aerials"].Opacity = value - 1;
    }
}

Re: Slide between layers

JayKappy — Sun, 12 Dec 2021 00:59:16 GMT

Thanks that worked out great.....as I said I think my problem was the Private sub and its parameters...
In my example I was unable to do this "Dim Value = e.NewValue"

The only way I could get mine to work was like this....but that was only with my specific layers not the ESRI ArcGISTiledMapServiceLayer map services...

        
        Dim value As Double = MySlider.Value

        Dim l_Parcels As ArcGISDynamicMapServiceLayer = TryCast(Me.MyMap.Layers("MG_Parcels"), ArcGISDynamicMapServiceLayer)
        Dim l_Parcels2 As ArcGISDynamicMapServiceLayer = TryCast(Me.MyMap.Layers("MG_Streets"), ArcGISDynamicMapServiceLayer)

        l_Parcels.Opacity = value 
        l_Parcels2.Opacity = 1 - value

Was trying this...

    Private Sub MultiLayerOpacityTurnOn1_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)

Your example...

I am confused on where and when to use RoutedPropertyChangedEventArgs or RoutedEventArgs...Maybe you can shed some light on that?

    Private Sub Slider_ValueChanged(ByVal sender As Object, ByVal e As RoutedPropertyChangedEventArgs(Of Double))

THANKS FOR YOUR HELP.....