ScheduleView determine position from time

[Alexander]

Hi,

is there a method to determine the current screen position (e.g. relative to the control) for a given time value? We need to draw some adorning visuals (lines) to show the current time.

Thanks,
Alexander

[Konstantina]

Hello Alexander,

Unfortunately, this cannot be achieved with the current implementation of the control. However, you can use the VisibleRange and the CurrentDate properties, which will give you all the information about the date in the view.

Hope this information helps.

Best wishes,
Konstantina
the Telerik team

[Alexander]

Hi Konstantina,

thank you for your reply.

This (and some other, forthcoming requirements) would actually be easy to implement if the internal classes PositioningData and PositioningHelper were externally accessible. Any thoughts on this?

Thanks,
Alexander

[Konstantina]

Hello Alexander,

Thank you for your question.

We will expose an Interface of the PositioningHelper in order to be usable.

Best wishes,
Konstantina
the Telerik team

[Alexander]

Hi Konstantina,

while we are at it :) , here is one more suggestion: Public access to time information of a TimeRulerItemBase instance?

Thanks again,
Alexander

[Yana]

Hello Alexander,

Could you please explain in more details your scenario and why you need to access TimeRulerItemBase? Thanks in advance

Kind regards,
Yana
the Telerik team

[Alexander]

Hello Yana,

this was related to an early attempt to solve my initial problem (see above). I could find the TimeRulerItem's via visual tree walking. But there was no way (short of reflection) to access the associated time information.

Anyway, we found a better solution.

Thanks,
Alexander

[Kristian]

Aleksander: I want to implement this feature in my calendar as well, and I am therefore wondering if you can give me some hints about how you did it?

Thanks,
Kristian

[Alexander]

Hi Kristian,

first, we got a reference (_scrollBar) to the ScheduleView ScrollBar via VisualTree walking and looking for "PART_HorizontalScrollBar".
then, assuming the names SchedulerView for RadScheduleView and ViewDef for TimelineViewDefinition:

var scale = ViewDef.MinTimeRulerExtent / SchedulerView.VisibleRange.Duration().TotalMinutes;
var elapsed = ((DateTime.Now - SchedulerView.VisibleRange.Start).TotalMinutes) * scale;
var x = elapsed - _scrollBar.Value;

x is the horizontal position for the current time, relative to the ScheduleView. You could put a transparent canvas in front of it and position a marker.

Hope this helps,
Alexander

[Kristian]

Hi Alexander,

Thank you for the hints! I am able to find the position for the current time now, but after that, I am kind of stuck.
Did you find a good way of updating the markers position every time the user scrolls the scrollbar? I can not seem to find any methods or events in RadScheduleView that can be useful for this kind of situation.

Thanks,
Kristian

[Alexander]

Hi Kristian,

you can use the Scroll event. Assuming the the reference to the scrollbar is in _scrollBar:

_scrollBar.Scroll += SchedulerView_Scroll;

And then implement an event handler to refresh your visuals.

Cheers,
Alexander

[Kristian]

Hi Alexander,

Thank you for the help! I had completely forgotten the events on the scrollbar itself.
I ended up subscribing to the ScrollBar's ValueChanged event, as this enabled me to update the marker when the user moves the scrollbar by using the mouse, the scrollwheel on the mouse, or when the user uses the up/down keys on the keyboard to navigate.

I also found a different, and maybe easier, way of obtaining the reference to the ScrollBar object:

Scrollbar verticalScrollBar = RadSchedule.ChildrenOfType<ScrollBar>().Where(s => s.Orientation == Orientation.Vertical).First();

RadSchedule is a reference to an RadScheduleView object.

You can read more about this way of obtaining the ScrollBar (and all other objects) in this blog post.

Cheers,
Kristian

[Alexander]

Hi Kristian,

this will be really useful, thanks!

Alexander