Hi Zimmer,
Thank you for contacting Syncfusion support.
Query 1:want to apply a dark style like blend to the SFTreeNavigator. Using syncfusionskin:SfSkinManager.VisualStyle="Blend" works for the control, but it does not look like UWP
We have confirmed that the issue, “SfSkinManager themes not applied correctly to the SfTreeNavigator while selecting or hovering the item ” is a defect and have logged a defect report. The fix for the issue will be available in our Volume 1 SP1 release which is expected to be available on end of February, 2018.
Query 2: I tried this: https://www.syncfusion.com/kb/4650/how-to-customize-the-style-of-sftreenavigator but i can't find the namespace "shared" in line 128. This is my favorite way.
We request you to include the namespace of “SfShared.WPF” in the name of “shared” in your application in order to resolve the error in your side. We have prepared a simple sample with the customized theme and it can be downloaded from the below location.
Query 3: Is there any example to automatically collapse the control? If it is not is use it should look like a hamburger menu like here: http://jkarger.de/2017/02/06/mahapps-hamburgermenu/
We request you to use our SfNavigationDrawer control in order to collapse the control as like hamburger menu. Please refer the below link for further reference.
Regards,
Keerthana J