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Control a button's enabled state using 3 multi data triggers

I want to control a buttons IsEnabled state based on the following conditions. The button should be active only when :
Checkbox 1 or Checkbox 2 is checked.
Listbox contains atleast 1 list item.
My issue is : I have to use separate MultiDataTrigger for achieving this behavior. When I add the code to the first multidata trigger, it doesn't work. ie even if list box doesn't have any items, the button is getting enabled.
So I need a solution for this. is there any possible way to include the 3rd multi data trigger condition along with the 2 conditions, so that few lines of code can be saved?
Thanks in advance. Please check my code below.
<Button.Style>
<Style TargetType="Button">
<Style.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding ElementName=Checkbox1, Path=IsChecked}" Value="False" />
<Condition Binding="{Binding ElementName=Checkbox2, Path=IsChecked}" Value="False" />
</MultiDataTrigger.Conditions>
<Setter Property="IsEnabled" Value="False" />
</MultiDataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding ElementName=ListBox, Path=Items.Count}" Value="0" />
</MultiDataTrigger.Conditions>
<Setter Property="IsEnabled" Value="False" />
</MultiDataTrigger>
</Style.Triggers>
</Style>
</Button.Style>

The MultiTrigger applies the associated setters or actions when all of the conditions are true (binary AND operation).
As mentioned, the trigger will fire on all the conditions being AND'd, which was why it didn't work when you put all the conditions together. The easiest way to produce an OR (without implementing a IMultiValueConverter), is to have multiple datatriggers (which imply a binary OR operation).
If you are intent on saving lines of code, you can use a DataTrigger instead of the MultiDataTrigger.
<DataTrigger Binding="{Binding ElementName=listView, Path=Items.Count }" Value="0">
<Setter Property="IsEnabled" Value="False" />
</DataTrigger>

WPF DataTrigger that accepts parameter?

I have the following style defined in my XAML to enable buttons only when something in the DataContext has changed (IsDirty = true) :
<!-- Style for Buttons to enable based on IsDirty value -->
<Style x:Key="EnableWhenDirtyButtonStyle" TargetType="{x:Type Button}"
BasedOn="{StaticResource ButtonStyle}">
<Setter Property="IsEnabled" Value="False" />
<Style.Triggers>
<!-- Enable button when something has changed -->
<DataTrigger Binding="{Binding RelativeSource={RelativeSource FindAncestor,
AncestorType={x:Type UserControl}}, Path=DataContext.IsDirty}" Value="True">
<Setter Property="Button.IsEnabled" Value="true" />
</DataTrigger>
</Style.Triggers>
</Style>
This works as long as there is only one DataContext within the UserControl. I now have the situation where I have 3 different DataViews so I have 3 different IsDirty values (i.e., CustomerTableIsDirty, OrderTableIsDirty, OrderDetailTableIsDirty). In this case I can create three new *DisableWhenDirtyButtonStyle in the UserControl like:
<Style x:Key="CustomerTableEnableWhenDirtyButtonStyle"
TargetType="{x:Type Button}"
BasedOn="{StaticResource ButtonStyle}">
<Setter Property="Button.IsEnabled" Value="False" />
<Style.Triggers>
<DataTrigger Binding="{Binding Path=CustomerTableIsDirty}" Value="true">
<Setter Property="Button.IsEnabled" Value="True" />
</DataTrigger>
</Style.Triggers>
</Style>
Is there a way to create a DataTrigger such that the binding value can be passed into the style as a parameter?
Alternatively, is there a way to add conditions to a MultiDataTrigger when inheriting a style via 'BasedOn' which would already have a MultiDataTrigger defined. For instance:
<Style x:Key="CustomerTableEnableWhenDirtyButtonStyle"
TargetType="{x:Type Button}"
BasedOn="{StaticResource EnableWhenDirtyButtonStyle}">
<!-- Add the following to existing MultiDataTrigger in EnableWhenDirtyButtonStyle -->
<Condition Binding="{Binding Path=CustomerTableIsDirty}" Value="true" />
</Style>
I CANNOT use MultiBinding as this style is part of a base project which gets used by multiple other projects (as a DLL). The users of this DLL would not be able to update the style to include the necessary Binding Path.

Instead of using 3 different names, just use a single name IsDirty.

Set Background of button based on Content or CustomDP value

I have a button whose Content property keeps changing based on certain conditions which are set from the ViewModel. Essentially it gets set a value from 0 to 1000.
I also have another custom DP property on the same button whose value can be set to a certain enum.
What I am trying to solve is as follows (and unfortunately have no idea how I should go about it):
If my button content value is 0 - background of the button should be Gray.
If my button content value is 1 - background of the button should be Yellow.
If my button content value is 1 & the Custom DP has a value set (not the default value) - background should change to Red.
If my problem statement was just dealing with setting a background based on the integer set on the content - I could easily use Converters (String to Brush) and set my background. But the last condition which is now setting my background based on custom DP value coming in - have no idea how to solve...
Can somebody please suggest me an approach - sample code to solve such a problem.

<Button Content="0">
<Button.Style>
<Style TargetType="Button">
<Style.Triggers>
<DataTrigger Binding="{Binding RelativeSource={RelativeSource Self},Path=Content}" Value="0">
<Setter Property="Background" Value="Gray"/>
</DataTrigger>
<DataTrigger Binding="{Binding RelativeSource={RelativeSource Self},Path=Content}" Value="1">
<Setter Property="Background" Value="Yellow"/>
</DataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding RelativeSource={RelativeSource Self}, Path=Content}" Value="1"/>
<Condition Binding="{Binding RelativeSource={RelativeSource Self}, Path=YourDP}" Value="YourValue"/>
</MultiDataTrigger.Conditions>
<MultiDataTrigger.Setters>
<Setter Property="Background" Value="Red"/>
</MultiDataTrigger.Setters>
</MultiDataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>

You can use multi-conditions triggers or multi data triggers. See this link and this link.

Datagrid multitrigger referencing values from code-behind

I'm still bloody green in WPF and have not yet fully grasped the concept behind it. I've got the following problem:
I want to set triggers in a datagrid depending on a precondition.
Example:
In my code-behind, I have a string variable, let's call it variableString. Now depending on the the value of variableString, I want to enable/disable the triggers inside a datagrid, that I have defined in XAML like:
if(variableString == "a")
then
XAML
<DataGrid AutoGenerateColumns="False" Margin="5,5,0,75" Name="dataGrid1" ItemsSource="Binding}">
<DataGrid.ItemContainerStyle>
<Style TargetType="DataGridRow">
<Style.Triggers>
<DataTrigger Binding="{Binding Path=SomeColumnName}" Value="someValue">
<Setter Property="Background" Value="White"/>
<DataTrigger Binding="{Binding Path=SomeColumName}" Value="someOtherValue">
<Setter Property="Background" Value="Red"/>
</Style.Triggers>
</Style>
</DataGrid.ItemContainerStyle>
Otherwise, if
if(variableString == "b")
then
Do Nothing`
I've already tried binding the string to the datacontext of the datagrid, but that was rather contra-productive, as it removes my binding to the database.
Can anyone help me here. An example, a push in the right direction etc...
I really like the options that WPF gives you, however it's that fundamental things, that were so easy to handle in WinForms, that drive me mad in WPF.
Thanks

I think you want a MultiDataTrigger, which allows you to base your trigger off of multiple values
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding Path=SomeColumnName}" Value="someValue" />
<Condition Binding="{Binding RelativeSource={RelativeSource AncestorType={x:Type Window}}, Path=variableString}" Value="A" />
</MultiDataTrigger.Conditions>
<Setter Property="Background" Value="White" />
</MultiDataTrigger>
To find your string in the code behind, you'll probably have to use some kind of RelativeSource binding to find the class containing that property. My example assumes there is a public property called variableString on the Window class

Applying a DataTrigger to a Button Whose Binding Comes From Another Control?

I'm trying to apply a DataTrigger to a Button and it depends on a property from the currently selected item of a TreeView. The idea is that I want to change the text of a Button depending on a property of the selected item.
What I have looks like this:
<Button x:Name="m_AddObject" Margin="192.708,0.909,6,6.363" Click="AddObject_Click" >
<DataTrigger Binding="{Binding ElementName=ObjectTreeView, Path=SelectedItem.Removable}" Value="true">
<Setter TargetName="m_AddObject" Property="Content" Value="Remove" />
</DataTrigger>
</Button>
But I can't get it to compile. The Setter complains about "Content" not being valid because it doesn't have a qualifying type name, but if I change it to "Button.Content" it then complains of "Object reference not set to an instance of an object".
I also tried:
<Setter TargetName="m_AddObject.Content" Value="Remove" />
While that compiles, it didn't work either.
I'm stumped.
Any ideas?
Thanks!

DataTriggers should be defined in a Style for the button. What you're trying to do above is essentially use a DataTriggers as the "label" (the "Content", as WPF puts it) for the button (instead of, say, "OK").
This is ad-hoc, so it might not be totally correct, but it's closer to what you want:
<Button x:Name="m_AddObject"
Margin="192.708,0.909,6,6.363"
Click="AddObject_Click">
<Button.Style>
<Style TargetType="{x:Type Button}">
<Style.Triggers>
<DataTrigger Binding="{Binding ElementName=ObjectTreeView, Path=SelectedItem.Removable}" Value="True">
<Setter Property="Content" Value="Remove" />
</DataTrigger>
</Style.Triggers>
</Style>
</Button.Style>
</Button>