How can I center text in morphic? I have a RectangleMorph subclass representing a "tile." I'd like to display a centered string label within the morph.
My current approach is to just override #drawOn: with:
TileMorph>>drawOn: aCanvas super drawOn: aCanvas. aCanvas drawString: 'hi' on: self innerBounds
However, that just always puts the text in the upper-left corner. (Code is from memory, so I may have got something wrong.)
By "center", I want the baseline-to-max-ascent for the font to be centered vertically (not the actual height of whatever characters I have), while the actual width is centered vertically.
Would it be better to use a StringMorph for placing text like this? I'm afraid I don't yet understand what layout options I'd need to use to make it work.
Thanks, - Johann
Hi Johann, just after you left IRC, I figured out an easy (though perhaps not the best) way to do what you want:
a := SimpleButtonMorph new openInWorld. a actWhen: #buttonDown. "turns off visible button behavior" a label: 'new label'. "lets you change the label to a different string of text" a clipSubmorphs: true. "true means that your text doesn't extend beyond the border of the button"
Hope this helps.
Lawson (saijanai_ on irc)
On 2/8/12 6:51 AM, Johann Hibschman wrote:
How can I center text in morphic? I have a RectangleMorph subclass representing a "tile." I'd like to display a centered string label within the morph.
My current approach is to just override #drawOn: with:
TileMorph>>drawOn: aCanvas super drawOn: aCanvas. aCanvas drawString: 'hi' on: self innerBoundsHowever, that just always puts the text in the upper-left corner. (Code is from memory, so I may have got something wrong.)
By "center", I want the baseline-to-max-ascent for the font to be centered vertically (not the actual height of whatever characters I have), while the actual width is centered vertically.
Would it be better to use a StringMorph for placing text like this? I'm afraid I don't yet understand what layout options I'd need to use to make it work.
Thanks,
- Johann
Beginners mailing list Beginners@lists.squeakfoundation.org http://lists.squeakfoundation.org/mailman/listinfo/beginners
On Wed, Feb 8, 2012 at 12:44 PM, Lawson English lenglish5@cox.net wrote:
Hi Johann, just after you left IRC, I figured out an easy (though perhaps not the best) way to do what you want:
a := SimpleButtonMorph new openInWorld. a actWhen: #buttonDown. "turns off visible button behavior" a label: 'new label'. "lets you change the label to a different string of text" a clipSubmorphs: true. "true means that your text doesn't extend beyond the border of the button"
Thanks, that's helpful. I don't think I'm going to use SimpleButtonMorph, since it builds in a fixed margin, but reading its implementation was useful. It makes a StringMorph and uses its #extent to do the centering, and I can just do the same thing. (And I can just look at StringMorph's #extent if I need to.)
If SimpleButtonMorph works by embedding a StringMorph, I think that's a sign that I should do that rather than override #drawOn.
Johann
Sure. My first pass at writing code using Morphic is to see if an existing class does what I want and then deciding if it is worth the time to "roll my own" using whatever insight I got from seeing how the existing code works.
#drawOn should only be used if you need to do things which don't use exisint morphs and/or need a great deal of speed. The built-in composition capabilities of Morphic are usually powerful enough to accomplish any kind of behavior using compositions of simpler morphs. Obviously, you don't create high-level paint programs using morphs as the pixels, but anything higher level than that is probably a good candidate for composition.
OTOH, if I was to write an educational program showing how line-drawing algorithms work, I probably WOULD use morphs as pixels. YMMV.
L
On 2/9/12 6:40 AM, Johann Hibschman wrote:
Thanks, that's helpful. I don't think I'm going to use SimpleButtonMorph, since it builds in a fixed margin, but reading its implementation was useful. It makes a StringMorph and uses its #extent to do the centering, and I can just do the same thing. (And I can just look at StringMorph's #extent if I need to.) If SimpleButtonMorph works by embedding a StringMorph, I think that's a sign that I should do that rather than override #drawOn. Johann _______________________________________________ Beginners mailing list Beginners@lists.squeakfoundation.org http://lists.squeakfoundation.org/mailman/listinfo/beginners
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Johann Hibschman -
Lawson English