3

Spent hours trying to figure this out and still haven't got it. None of the documentation mentions anything about it. Is this something rebol just can't do without manually having to rearrange everything with origin?

Perhaps I'm just expecting too much?

edit: well I've discovered a hack: indent num, then indent -num on the next line . Out of all the spectacular features of this language why couldn't they have just added a simple command like center?

HostileFork says dont trust SE
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user2020783
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3 Answers3

5

There is a CENTER-FACE function you can reuse to align faces, but unfortunately it doesn't work very well from my experience. Here is a simpler replacement version that should do the trick: 

center-face: func [face [object!] parent [object!]][
    face/offset: parent/size - face/size / 2 
]

Here is a usage example:

lay: layout [
    size 300x300
    b: button "Hello World"
]
center-face b lay
view lay
DocKimbel
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  • the above actually will give you errors ... 'LAY doesn't have a value from within the layout block. – moliad Feb 02 '13 at 16:28
3

First off, VID is not Rebol, but a demonstration dialect written by the author, Carl Sassenrath, to demonstrate how interfaces could be dialected in Rebol. There are others including RebGUI ( http://www.dobeash.com/rebgui.html ) though I suspect there isn't a way to center buttons there either as neither author considered it important.

You can also use PAD to align the cursor close to the center of the layout.

Graham Chiu
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  • Span directives in RebGUI can be used to align widgets within layouts. http://www.dobeash.com/RebGUI/user-guide.html#21 – Brian Tiffin Jan 31 '13 at 23:45
3

We can't center or align stuff based on the window itself because controls do not have any way to refer to their parent face until AFTER the parent has had 'SHOW called on it.

face/parent-face isn't set until the parent has been shown. So in normal VID you need to tweak the gui just after the initial layout & view has been done.

here is a little script which shows how to center any face, after its been shown at least once.

view/new is used to delay event handling, in order to modify the layout.

rebol []

center: func [face][
    face/offset/x: (face/parent-face/size/x / 2) - (face/size/x / 2)
    show face
]

view/new layout [
    across
    t: h1  "This is a centered title!" 
    return
    button "1"
    button "2"
    button "3"
    button "4"
]

center t

do-events
moliad
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