Xaml switch between TextBlock and TextBox - wpf

Question

I've noticed that TextBoxes are very slow and create performance issues when the Text is changed dynamically by code (I need to change the Text continuosly to 10-15 TextBoxes at the same time), so, as a workaround, I've created a custom control with a TextBlock and a TextBox:
The TextBlock is used in almost all time.
The TextBox is used only when I need to edit the Text inside the control with keyboard.
My solution is to change the template and use the TextBox when the control is focused:
(Value is a string Dependency Property)
<Style TargetType="{x:Type local:CustomControl1}">
<Setter Property="Value" Value="Val"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type local:CustomControl1}">
<Border Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
<TextBlock HorizontalAlignment="Center" VerticalAlignment="Center" Text="{TemplateBinding Value}"/>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="IsFocused" Value="True">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type local:CustomControl1}">
<Border Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
<TextBox HorizontalContentAlignment="Center" VerticalContentAlignment="Center"
Text="{Binding Path=Value, RelativeSource={RelativeSource TemplatedParent}, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"/>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Trigger>
</Style.Triggers>
</Style>
But when I click on the control nothing happens.
I think that the problem is that the "focus state" is passed to the internal TextBox, and the control loses the "focus state".
There is a better way to create a custom "TextBox" control like this, or a way to resolve this problem?

Answer 1

You don't need a custom control for this, that's just adding unnecessary overhead. What you're trying to create is still a TextBox, with all the usual behavior of a TextBox (focus etc). All you need to do is change the template to a TextBlock when it's not in focus:
<Window.Resources>
<Style TargetType="{x:Type TextBox}">
<Style.Triggers>
<Trigger Property="IsFocused" Value="False">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TextBox}">
<TextBlock Text="{TemplateBinding Text}" />
</ControlTemplate>
</Setter.Value>
</Setter>
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
<StackPanel>
<TextBox Text="Hello World" />
<TextBox Text="Goodbye World" />
</StackPanel>