Added empty HeaderTemplate to NavigationView

[nmetulev]

Issue: #1644

PR Type

What kind of change does this PR introduce?

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build or CI related changes
[ ] Documentation content changes
[ ] Sample app changes
[ ] Other... Please describe:

PR Checklist

Please check if your PR fulfills the following requirements:

• Tested code with current supported SDKs

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

[skendrot]

Won't this require users to set a HeaderTemplate? Meaning that even if they set a Header that it will not show?

[nmetulev]

The HamburgerMenu doesn't have a header, there is no way to modify it without re-templating it anyway

[skendrot]

So this wouldn't be needed then. If the Header of the NavigationView isn't being set there is no need for a HeaderTemplate

[nmetulev]

Just tried it. Looks like the NavigationView has a default template for the Header, so if you don't specify anything, it binds a TextBlock to the DataContext by default

[skendrot]

That's standard. But the Content of the HeaderTemplate should be set to the Header itself

<ContentPresenter Content="{TemplateBinding Header}" ContentTemplate="{TemplateBinding HeaderTemplate}"/>

[nmetulev]

Not sure what you mean, the HamburgerMenu doesn't have a Header and HeaderTemplate

[skendrot]

Yes, that would be for the NavigationView. There shouldn't be any reason to set an empty header template because the header content would be null

[nmetulev]

I'm probably doing something wrong, I haven't been able to get it work any other way other then setting a blank template. Setting Header to null doesn't work. Setting header to an empty grid doesn't work.

[windowstoolkitbot]

This PR is linked to unclosed issues. Please check if one of these issues should be closed: #1644