We Keep Coding

Why isnt my button using the style I created?

So I decided to try to give a button a custom style.
Yet when I assign it the Style it wont use it, why is this?
I tried creatinga button with a textbox, image and a ellipse with a label on that too.
I want the button to change color when I hover over it but its making my button disappear.
Window resources
<Window.Resources>
<Style x:Key="MenuButton" TargetType="{x:Type Button}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<ControlTemplate.Triggers>
<Trigger Property="Background" Value="#272727">
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Foreground" Value="Gray"></Setter>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
And then the button
<Button Background="Transparent"
Style="{StaticResource MenuButton}"
Height="25"
BorderThickness="0">
<StackPanel Orientation="Horizontal">
<Image Source="Resources/earth-globe.png"
Height="20"
Width="20"
HorizontalAlignment="Left"
Margin="0,0,5,0"
UseLayoutRounding="True"
RenderOptions.BitmapScalingMode="Fant"/>
<Label Content="Websites"
Foreground="White"
VerticalAlignment="Center"
Width="100"
Height="24"/>
<Grid HorizontalAlignment="Right" Height="20" Width="20">
<Ellipse Width="20"
Height="20"
Fill="#555555"
Margin="0,0,0,0">
</Ellipse>
<TextBlock Text="10"
HorizontalAlignment="Center"
VerticalAlignment="Center"
FontSize="12"
TextAlignment="Center"
Foreground="White"/>
</Grid>
</StackPanel>
</Button>

You do not want to put that style in the template portion of the style because a template is used for customizing the full control look (i.e. making a button a circle) and a way of giving the developer more flexibility over styling. What you could do is make a style that is applied to the button. Instead try this:
<Window.Resources>
<Style x:Key="MenuButton" TargetType="{x:Type Button}">
<Setter Property="Background" Value="#272727" />
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Foreground" Value="Gray" />
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
If you did want to modify the template property though, also a valid approach you need to add a <ContentPresenter />. See the below example:
<Window.Resources>
<Style x:Key="MenuButton" TargetType="{x:Type Button}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<ContentPresenter />
<ControlTemplate.Triggers>
<Trigger Property="Background" Value="#272727">
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Foreground" Value="Gray"></Setter>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
However, with the minimal styling you have it seems like a poor use case to modify the template and I would recommend the first approach.

Add missing ContentPresenter to your DataTemplate.
<Style x:Key="MenuButton" TargetType="{x:Type Button}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<ContentPresenter /> <!--This thing was missing-->
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="RED" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>

Customising ToggleButton state images using XAML

I am currently using the XAML below to change the image on a toggle button for each state. How can I define a template or style that will allow me to define the images that are to be used in the button definition such that I don't have to repeat everything below for each button. Is this even possible ?
Ideally I would like to define a template with properties such as 'checkedImage', 'uncheckedImage' and then set these properties in the button definition in Designer.
I would also like the button to prevent the display of any other states or animations but I can't seem to prevent the background changing when the button is selected or when there is a mouseover. Are there some additional states that I don't have defined below?
Sample code (XAML, C#) for the style or template and for the actual toggle button definition would be appreciated. Also any references to 'simple' samples and explanations would be appreciated.
Thanks
EDIT: Update with my latest attempt...
This almost works - the correct image never gets displayed when the button is Checked. Any ideas what I am missing here?
<Style x:Key="ImgToggleButton" TargetType="ToggleButton">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ToggleButton">
<Grid x:Name="GD" Background="White">
<ContentPresenter x:Name="CP" Content="{TemplateBinding Content}"></ContentPresenter>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Content">
<Setter.Value>
<Image Source="{Binding Path=Tag, RelativeSource={RelativeSource AncestorType=ToggleButton}}" Stretch="Uniform"/>
</Setter.Value>
</Setter>
<Setter TargetName="GD" Property="Background" Value="{DynamicResource ThemeSolidColorBrushBlue}"/>
</Trigger>
<Trigger Property="IsChecked" Value="False">
<Setter TargetName="GD" Property="Background" Value="White"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<!-- Nothing so we have no change-->
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
And here is the button definition
<ToggleButton x:Name="allTestsToggleButton" Tag="Asset/AllTestsButton_1.png" Style="{DynamicResource ImgToggleButton}" ClickMode="Press" Checked="allTestsToggleButton_Checked" Unchecked="allTestsToggleButton_Unchecked" Grid.Row="2" Grid.Column="3" Grid.ColumnSpan="5">
<ToggleButton.Content>
<Image Source="Assets/AllTestsButton_0.png" Stretch="Uniform"/>
</ToggleButton.Content>
</ToggleButton>
Setting TargetName="CP" does not work either
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter TargetName="CP" Property="Content">
<Setter.Value>
<Image Source="{Binding Path=Tag, RelativeSource={RelativeSource AncestorType=ToggleButton}}" Stretch="Uniform"/>
</Setter.Value>
</Setter>
<Setter TargetName="GD" Property="Background" Value="{DynamicResource ThemeSolidColorBrushBlue}"/>
</Trigger>
<Trigger Property="IsChecked" Value="False">
<Setter TargetName="GD" Property="Background" Value="White"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<!-- Nothing so we have no change-->
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>

Update1
You can use this style for multiple button with different images and I have used tag for storing image for checked state true and use templatebinding for default look i.e state=false
<Window.Resources>
<BitmapImage x:Key="imag1" UriSource="image1.jpg"></BitmapImage>
<BitmapImage x:Key="imag2" UriSource="path.jpg"></BitmapImage>
<Style TargetType="ToggleButton">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ToggleButton">
<Grid x:Name="GD" Background="{TemplateBinding Background}">
<ContentPresenter></ContentPresenter>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter TargetName="GD" Property="Background">
<Setter.Value>
<ImageBrush ImageSource="{Binding Path=Tag, RelativeSource={RelativeSource AncestorType=ToggleButton}}"></ImageBrush>
</Setter.Value>
</Setter>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<ToggleButton x:Name="sampleTestToggleButton" Tag="{StaticResource imag2}" ClickMode="Press" Grid.Row="4" Grid.Column="3" BorderBrush="Transparent" Foreground="Transparent">
<ToggleButton.Background>
<ImageBrush ImageSource="{StaticResource imag1}"></ImageBrush>
</ToggleButton.Background>
</ToggleButton>
Update2:
Hope this helps.Run this code separately.It is working fine here.
<Window.Resources>
<Style x:Key="ImgToggleButton" TargetType="ToggleButton">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<Image Stretch="Uniform" Source="{Binding Content,RelativeSource={RelativeSource TemplatedParent}}"></Image>
</DataTemplate>
</Setter.Value>
</Setter>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ToggleButton">
<Grid x:Name="GD" Background="White">
<ContentPresenter></ContentPresenter>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="ContentTemplate">
<Setter.Value>
<DataTemplate>
<Image Stretch="Uniform" Source="{Binding Path=Tag, RelativeSource={RelativeSource AncestorType=ToggleButton}}"></Image>
</DataTemplate>
</Setter.Value>
</Setter>
</Trigger>
<Trigger Property="IsChecked" Value="False">
<Setter TargetName="GD" Property="Background" Value="White"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<!-- Nothing so we have no change-->
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<ToggleButton x:Name="allTestsToggleButton" Content="imag2.jpg" Tag="imag1.jpg" Style="{DynamicResource ImgToggleButton}" ClickMode="Press" Grid.Row="2" Grid.Column="3" Grid.ColumnSpan="5"/>

I think, you need for the ability to use vector graphics in WPF. In this case, to use the Path, where in Data to the specified coordinates on which the object is drawn MSDN.
Advantages:
Do not store it in the files, smaller size
Do not store this files in Resources
Dynamically changing color, size and the whole shape
The Minuses, in my opinion:
You can not always find the right Data for the Path
About minus: There are special sites, like www.modernuiicons.com and utilities for converting the image to Data. For converting Image to Vector graphics (Path) use Inkscape, him free and very useful. For more information see this link:
Vectorize Bitmaps to XAML using Potrace and Inkscape
Example
<Window.Resources>
<Style x:Key="styleCustomCheckBox" TargetType="{x:Type CheckBox}">
<Setter Property="FontFamily" Value="Verdana" />
<Setter Property="FontSize" Value="14" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type CheckBox}">
<StackPanel Orientation="Horizontal">
<Path x:Name="MyPin" Width="18" Height="18" Stretch="Fill" Fill="#FF000000"
Data="F1 M 56.1355,32.5475L 43.4466,19.8526C 42.7886,20.4988 42.298,21.2123 41.9749,21.9932C 41.6519,22.7741 41.4903,23.5729 41.4903,24.3895C 41.4903,25.1942 41.6529,25.987 41.9779,26.7679L 34.0577,34.6821C 33.3918,34.3372 32.6991,34.0776 31.9796,33.9032C 31.2601,33.7288 30.5298,33.6415 29.7885,33.6415C 28.623,33.6415 27.4953,33.8526 26.4052,34.2748C 25.315,34.697 24.3419,35.3342 23.4856,36.1865L 30.2344,42.9174L 25.9027,47.9032L 22.6532,51.8425L 20.5988,54.5836C 20.1212,55.2892 19.8823,55.753 19.8823,55.975L 19.8645,56.0701L 19.9002,56.088L 19.9002,56.1474L 19.9358,56.1058L 20.0131,56.1236C 20.2351,56.1236 20.6989,55.8888 21.4045,55.419L 24.1457,53.3765L 28.0849,50.1151L 33.0945,45.7775L 39.8016,52.5025C 40.6579,51.6462 41.2961,50.6731 41.7163,49.5829C 42.1365,48.4928 42.3466,47.367 42.3466,46.2056C 42.3466,45.4603 42.2603,44.729 42.0879,44.0115C 41.9155,43.294 41.6548,42.6003 41.3069,41.9304L 49.2202,34.0161C 50.0011,34.3372 50.7939,34.4978 51.5986,34.4978C 52.4192,34.4978 53.2189,34.3362 53.9979,34.0132C 54.7768,33.6901 55.4894,33.2015 56.1355,32.5475 Z "/>
<ContentPresenter VerticalAlignment="Center" Margin="10,0,0,0" />
</StackPanel>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="False">
<Setter TargetName="MyPin" Property="Data" Value="F1 M 32.3691,30.2225L 33.2253,29.3901L 15.361,11.5258C 13.9814,12.7067 12.6951,13.9936 11.5148,15.3738L 26.6252,30.4842C 27.743,30.1631 28.8767,30.0025 30.0263,30.0025C 30.8191,30.0025 31.6,30.0759 32.3691,30.2225 Z M 45.5039,49.3629L 60.6292,64.4826C 62.0123,63.2996 63.3017,62.0101 64.4846,60.6268L 46.6218,42.7866L 45.7834,43.619L 45.9439,44.7726L 45.9915,45.9261L 45.8785,47.6713L 45.5039,49.3629 Z M 56.1355,32.5475L 43.4466,19.8526C 42.7886,20.4987 42.298,21.2123 41.9749,21.9932C 41.6519,22.7741 41.4903,23.5729 41.4903,24.3895C 41.4903,25.1942 41.6529,25.987 41.9779,26.7679L 34.0577,34.6821C 33.3918,34.3372 32.6991,34.0776 31.9796,33.9032C 31.2601,33.7288 30.5298,33.6415 29.7885,33.6415C 28.623,33.6415 27.4953,33.8526 26.4052,34.2748C 25.315,34.697 24.3419,35.3342 23.4856,36.1865L 30.2344,42.9174L 25.9027,47.9032L 22.6532,51.8425L 20.5988,54.5836C 20.1212,55.2892 19.8823,55.753 19.8823,55.975L 19.8645,56.0701L 19.9002,56.0879L 19.9002,56.1474L 19.9358,56.1058L 20.0131,56.1236C 20.2351,56.1236 20.6989,55.8888 21.4045,55.419L 24.1457,53.3765L 28.0849,50.1151L 33.0945,45.7775L 39.8016,52.5025C 40.6579,51.6462 41.2961,50.6731 41.7163,49.5829C 42.1365,48.4928 42.3466,47.367 42.3466,46.2056C 42.3466,45.4603 42.2603,44.729 42.0879,44.0115C 41.9155,43.294 41.6548,42.6003 41.306,41.9304L 49.2202,34.0161C 50.0011,34.3372 50.7939,34.4978 51.5986,34.4978C 52.4192,34.4978 53.219,34.3362 53.9979,34.0132C 54.7768,33.6901 55.4894,33.2015 56.1355,32.5475 Z " />
<Setter TargetName="MyPin" Property="Fill" Value="Gray" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<StackPanel Orientation="Vertical" HorizontalAlignment="Center">
<CheckBox Height="35"
Style="{StaticResource styleCustomCheckBox}"
Content="MySolution1" />
<CheckBox Height="35"
Style="{StaticResource styleCustomCheckBox}"
Content="MySolution2" />
</StackPanel>
Output

How to display validation error in button bound to command

I am developing an app and trying to stick to an MVVM model, I have a button that is just bound to a command. Currently the command can be enabled / disabled and greys out the button when the command is set to CanExecute false. But I want to add the ability to show validation errors on the button (by changing its color to red, maybe showing a tooltip).
The validation is currently already shown in another location in the UI, but the users are getting annoyed that the button is enabled and they click it only to have a message box pops up telling them they shouldn't of clicked the button because there is a validation error. But just disabling the button completely without showing them why would make the users confused(since they overlook the large red validation error at the bottom of the screen). So how can I show additional information on the save button?
This is my current button xaml:
<Button Name="SaveDataPointButton" Style="{StaticResource ImageButton}" Command="{Binding OpenDataPoint.SaveDataPointEditsCommand}" Margin="5,0" VerticalAlignment="Stretch">
<Image Source="save.png" Stretch="None" ToolTip="Save Edits"/>
</Button>
And the style that is changing its appearance when IsEnabled is false, is it possible to somehow inspect some other command state from the style to make the button red during validation errors?
<!-- Style for all of the nav and save buttons in the datapoints view -->
<Style x:Key="ImageButton" TargetType="Button">
<Setter Property="SnapsToDevicePixels" Value="true"/>
<Setter Property="OverridesDefaultStyle" Value="true"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Border
x:Name="Border"
BorderThickness="0">
<ContentPresenter
Margin="2"
HorizontalAlignment="Center"
VerticalAlignment="Center"
RecognizesAccessKey="True"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="true">
<Setter TargetName="Border" Property="Background">
<Setter.Value>
<SolidColorBrush Color="LightGray"/>
</Setter.Value>
</Setter>
</Trigger>
<Trigger Property="IsPressed" Value="true">
<Setter TargetName="Border" Property="Background">
<Setter.Value>
<SolidColorBrush Color="Gray"/>
</Setter.Value>
</Setter>
</Trigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Opacity" Value="0.3"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="Command" Value="{x:Null}">
<Setter Property="IsEnabled" Value="False"/>
</Trigger>
</Style.Triggers>
</Style>

I ended up using a DataTrigger bound to another property on the view model to change the background color, but because I was setting a ControlTemplate in the style, the only way I could figure out to make the DataTrigger apply a background change was to copy the entire style and put the DataTrigger on the Border element in the control template. Since apparently you can't reference a child element from the new ControlTemplate from outside that control template.
<!-- Style for all of the nav and save buttons in the datapoints view -->
<Style x:Key="ImageSaveButton" TargetType="Button">
<Setter Property="SnapsToDevicePixels" Value="true"/>
<Setter Property="OverridesDefaultStyle" Value="true"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Border
x:Name="Border"
BorderThickness="0">
<Border.Style>
<Style TargetType="Border">
<Style.Triggers>
<DataTrigger Binding="{Binding OpenDataPoint.HasValidationError}" Value="True">
<Setter Property="Background" Value="Red"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Border.Style>
<ContentPresenter
Margin="2"
HorizontalAlignment="Center"
VerticalAlignment="Center"
RecognizesAccessKey="True"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="true">
<Setter TargetName="Border" Property="Background">
<Setter.Value>
<SolidColorBrush Color="LightGray"/>
</Setter.Value>
</Setter>
</Trigger>
<Trigger Property="IsPressed" Value="true">
<Setter TargetName="Border" Property="Background">
<Setter.Value>
<SolidColorBrush Color="Gray"/>
</Setter.Value>
</Setter>
</Trigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Opacity" Value="0.3"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="Command" Value="{x:Null}">
<Setter Property="IsEnabled" Value="False"/>
</Trigger>
</Style.Triggers>
</Style>

ResourceDictionary Style Triggers not working

from the following Trigger only the Foreground Setter is working. I do not understand why.
<Style TargetType="{x:Type Button}">
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="Red"/>
<Setter Property="BorderBrush" Value="Red"/>
<Setter Property="Foreground" Value="Red"/>
</Trigger>
Thanks for any help.

The reason this doesn't work is because the default Button template uses a ButtonChrome that draws the border and background and handles states like mouseover and disabled depending on the Windows theme (e.g. Windows XP style, Windows 7 style).
In order to allow your triggers to be applied, you will need to define a custom Button template that uses standard stylable WPF elements, like Border, instead of ButtonChrome. Here's a bare-bones working example:
<Button Content="button">
<Button.Style>
<Style TargetType="Button">
<Setter Property="BorderThickness" Value="3" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<Border Background="{TemplateBinding Property=Background}"
BorderBrush="{TemplateBinding Property=BorderBrush}"
BorderThickness="{TemplateBinding Property=BorderThickness}">
<ContentPresenter />
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Background" Value="Red" />
<Setter Property="BorderBrush" Value="Green" />
<Setter Property="Foreground" Value="Blue" />
</Trigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>

Button in WPF has a default control template. The correct way to override the Button's default behavior is by overriding default control template. This can be done with something similar to below:
<Button Width="100" Height="50" Content="Click Me!">
<Button.Template>
<ControlTemplate TargetType="{x:Type Button}">
<Border x:Name="bdr_main" CornerRadius="20" Margin="4" BorderThickness="1" BorderBrush="Black" Background="LightGray">
<ContentPresenter VerticalAlignment="Center" HorizontalAlignment="Center" Margin="8,6,8,6" ContentSource="Content" />
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="bdr_main" Property="Background" Value="LightGreen"/>
</Trigger>
<Trigger Property="IsPressed" Value="True">
<Setter TargetName="bdr_main" Property="Background" Value="Red"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Button.Template>
Found # http://harishasanblog.blogspot.com/2011/02/ismouseover-trigger-not-working-in-wpf.html
Hope it helps!

Try using the trigger on the controltemplate.
<ResourceDictionary>
<Style x:Key="TestButton" TargetType="Button">
<Setter Property="Height" Value="30" />
<Setter Property="Width" Value="30" />
<Setter Property="Background" Value="Transparent" />
<Setter Property="Foreground" Value="Green" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Button">
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Foreground" Value="Purple" />
</Trigger>
</ControlTemplate.Triggers>
<Grid>
<Rectangle Fill="{TemplateBinding Foreground}" />
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ResourceDictionary>

Creating a WPF Button that dynamically changes its content

I have created a custom WPF button that has 3 states (normal, clicked, disabled). For each state I have a different image. I use this general button in different places in my project and each time I load a different images using a property in the .CS file.
<Button.Resources>
<ImageSource x:Key="Normal">..\Resources\DefaultNormal.png</ImageSource>
<ImageSource x:Key="Disabled">..\Resources\DefaultDisabled.png</ImageSource>
<ImageSource x:Key="Pressed">..\Resources\DefaultPressed.png</ImageSource>
</Button.Resources>
<Button.Template>
<ControlTemplate TargetType="{x:Type Button}">
<Grid>
<Image Name="normal" Source="{DynamicResource Normal}" Stretch="Fill"/>
<Image Name="pressed" Source="{DynamicResource Pressed}" Stretch="Fill" Visibility="Hidden"/>
<Image Name="disabled" Source="{DynamicResource Disabled}" Stretch="Fill" Visibility="Hidden"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsPressed" Value="True">
<Setter TargetName="normal" Property="Visibility" Value="Hidden"/>
<Setter TargetName="pressed" Property="Visibility" Value="Visible"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter TargetName="normal" Property="Visibility" Value="Hidden"/>
<Setter TargetName="disabled" Property="Visibility" Value="Visible"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Button.Template>
Now I would like to do the same with the button's text/content but I can't find something similar to ImageSource for text. Is there something like that?, or is there a different way to change the text dynamically?

It looks like you just need to add a new element to your control template; then you can access it in the triggers.
<ControlTemplate TargetType="{x:Type Button}">
<Grid>
<Image Name="normal" Source="{DynamicResource Normal}" Stretch="Fill"/>
<Image Name="pressed" Source="{DynamicResource Pressed}" Stretch="Fill" Visibility="Hidden"/>
<Image Name="disabled" Source="{DynamicResource Disabled}" Stretch="Fill" Visibility="Hidden"/>
<TextBlock Name="text" Text="{TemplateBinding Content}" VerticalAlignment="Center" HorizontalAlignment="Center" />
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsPressed" Value="True">
<Setter TargetName="normal" Property="Visibility" Value="Hidden"/>
<Setter TargetName="pressed" Property="Visibility" Value="Visible"/>
<Setter TargetName="text" Property="Text" Value="Pressed :)"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter TargetName="normal" Property="Visibility" Value="Hidden"/>
<Setter TargetName="disabled" Property="Visibility" Value="Visible"/>
<Setter TargetName="text" Property="Text" Value="Disabled :("/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
Here I added a TextBlock over the images, and changed the text on press/disabled states.
If you wanted to add the text strings as resources within the control, then use the System namespace to reference the String type. xmlns:clr="clr-namespace:System;assembly=mscorlib
<Button.Resources>
<clr:String x:Key="NormalText">Normal</clr:String>
<clr:String x:Key="DisabledText">Disabled</clr:String>
<clr:String x:Key="PressedText">Pressed</clr:String>
</Button.Resources>

Try this:
1) Add to namespace:
xmlns:system="clr-namespace:System;assembly=mscorlib"
2) Add to resource this entry:
<system:String x:Key="myMessage">Button state: clicked!</system:String>
And now you can use in TextBlock Text property "myMessage" or as Button content:
<Button Content="{StaticResource myMessage}" />