Mac OS - Live ScrollBar, pleaaaase

[Niffo]

Pleaaase, is it possible to set the parameter "liveTracking" to "True" when calling the CreateScrollBarControl() API from the Gadget library of PB ? ... so that we can have a "Live ScrollBar" when using the SetControlAction() API to assign a callback function to it.

This already works with PB "TrackBar Gadget", so i assume it is created with the CreateSliderControl() API with the "liveTracking" parameter set to "True".

Code sample to illustrate this (try to drag the sliders/scrollbars) :

Code: Select all

ImportC "/System/Library/Frameworks/Carbon.framework/Carbon"
   NewControlActionUPP.l(*userRoutine)
   SetControlAction(theControl.l, actionProc.l)
   CreateScrollBarControl(window.l, *boundsRect, value.l, minimum.l, maximum.l, viewSize.l, liveTracking.b, liveTrackingProc.l, *outControl)
   ShowControl(theControl.l)
EndImport

Structure Rect
   top.w
   left.w
   bottom.w
   right.w
EndStructure

OpenWindow(0, 100, 100, 500, 200, "Test")

TrackBarGadget(0, 10, 10, 200, 20, 0, 10)
TextGadget(1, 230, 10, 200, 20, "'normal' slider")

TrackBarGadget(2, 10, 50, 200, 20, 0, 10)
TextGadget(3, 230, 50, 200, 20, "'live' slider")

ScrollBarGadget(4, 10, 90, 200, 20, 0, 10, 1)
TextGadget(5, 230, 90, 200, 20, "'normal' scrollbar")

ScrollBarGadget(6, 10, 130, 200, 20, 0, 10, 1)
TextGadget(7, 230, 130, 200, 20, "'live' scrollbar (does not work)")

Rect.Rect : Rect\left = 10 : Rect\top = 170 : Rect\right = 210 : Rect\bottom = 190
CreateScrollBarControl(WindowID(0), @Rect, 0, 0, 10, 1, #True, #Null, @APIScrollBar)
ShowControl(APIScrollBar)
TextGadget(8, 230, 170, 200, 20, "API created 'live' scrollbar")

ProcedureCDLL LiveTrackingProc()
EndProcedure

ControlActionUPP = NewControlActionUPP(@LiveTrackingProc())
SetControlAction(GadgetID(2), ControlActionUPP)
SetControlAction(GadgetID(6), ControlActionUPP)
SetControlAction(APIScrollBar, ControlActionUPP)

Repeat : Until WaitWindowEvent() = #PB_Event_CloseWindow

[Polo]

Hi,

Not that I want to bump this topic (well, I did, sorry ) but this change would save me a lot of API calls, and only requires a 5 second fix from PB team
Thanks in advance!

[DoubleDutch]

It would be very handy on Windows too! (don't know if it is possible though).

[Polo]

It would be very handy on Windows too! (don't know if it is possible though).

Yes, with a workaround (available on this forum), like on MacOSX, but in order to do the Mac workaround the PB scrollbars need to be changed, hence the request

[DoubleDutch]

Having live scroll bars makes it possible to do some very interesting canvasgadget work. For example I've done a word-wrapping tree gadget that works directly from my packed data - I've no need to load the tree as it renders directly.


http://ɯoɔ.com/images/tree.jpg

I use the live scroll bar routines that I found on the forum to allow the user to scroll up/down the tree, but if would be much nicer if it was 'native'.

[kenmo]

I'm missing the obvious here... what do you guys mean by "live" scrollbar? (Don't have a Mac or even PB available to test right now.)

[Polo]

I'm missing the obvious here... what do you guys mean by "live" scrollbar? (Don't have a Mac or even PB available to test right now.)

When you scroll using the buttons, you receive an event when you release the button. We want the event when the position has changed (even if it's still changing).

And the specific request for Mac is that even though you move the scrollbar, it won't get moved until you release the button which is very non-standard

[kenmo]

Ah okay. I think ProgressBarGadgets do that, right? I rarely use ScrollBarGadgets, but that would definitely be useful on all platforms.

[Polo]

Can the live scrollbar on the mac be enabled for 4.60 final please?
It only requires to add a flag !

[Lebostein]

Any news about geting trackbar positions while sliding? At the moment on Mac OS all events are spitted out only if you release the trackbar...

[wilbert]

Any news about geting trackbar positions while sliding? At the moment on Mac OS all events are spitted out only if you release the trackbar...

Use BindEvent.

Code: Select all

Procedure Trackbar0Callback()
  Debug GetGadgetState(0)
EndProcedure

OpenWindow(0, 0, 0, 320, 200, "TrackBarGadget", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
TrackBarGadget(0, 10,  40, 250, 20, 0, 10000)
SetGadgetState(0, 5000)

BindEvent(#PB_Event_Gadget, @Trackbar0Callback(), 0, 0)

Repeat
Until WaitWindowEvent() = #PB_Event_CloseWindow

[Lebostein]

Thanks! I miss a hint in documentation on page TrackBarGadget() and ScrollBarGadget(). A small section with a link to BindEvent....

[wilbert]

Thanks! I miss a hint in documentation on page TrackBarGadget() and ScrollBarGadget(). A small section with a link to BindEvent....

It is mentioned on the BindEvent page

It also allows to have real-time event notifications as the callback can be invoked as soon as the event occurs (useful for ScrollBarGadget(), live window resize, etc.)

but I agree it would be nice to mention it on the TrackBarGadget and ScrollBarGadget pages as well.