Margin and Padding of HelperText don't match the specs

[ElieTaillard]

Margin and Padding of HelperText don't match the specs.
The HelperText should be aligned with the Text.
This correction have to be made on :

• FilledPassword
• FilledDatePicker
• FilledCombobox
• OutlinedPassword
• OutlinedDatePicker
• OutlinedCombobox

I have already fixed the problem for most of the styles by taking the example of this PR : #2217
You can check my changes here : ElieTaillard@eca7a83
I just need to fix the problem for the FilledCombobox, but a trigger is missing in MaterialDesignTheme.ComboBox.xaml for the property wpf:TextFieldAssist.HasFilledTextField

Should I add this trigger in the template?

[Keboo]

Yes I am good simply adding in that trigger.

[ElieTaillard]

I tried to add

<Trigger Property="wpf:TextFieldAssist.HasFilledTextField" Value="True">
      <Setter Property="Padding" Value="16 8 12 8" />
      <Setter TargetName="HelperTextWrapper" Property="Margin" Value="16 0 0 0" />
</Trigger>

in the <ControlTemplate.Triggers> tag, but it doesn't change the padding and margin of the HelperText for the FilledCombobox

Do I have to change anything in the code behind to make it work?

[Keboo]

So a few things need to be changed for that trigger to work:

1. Make sure the trigger is being applied in the triggers section of the MaterialDesignFloatingHintComboBoxTemplate control template.
2. Make sure to give the Canvas around the help text the name "HelperTextWrapper"
3. In the MaterialDesignFilledComboBox style set the TextFieldAssist.HasFilledTextField attached property to true (was a little surprised this was missing).

[ElieTaillard]

Thank you, this setter was missing <Setter Property="wpf:TextFieldAssist.HasFilledTextField" Value="True"/>