[MacPorts] #57577: qt4-mac : set the graphicssystem via qtconfig

[MacPorts]

#57577: qt4-mac : set the graphicssystem via qtconfig
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  Reporter:  RJVB         |      Owner:  michaelld
      Type:  enhancement  |     Status:  assigned
  Priority:  Normal       |  Milestone:
 Component:  ports        |    Version:
Resolution:               |   Keywords:  haspatch
      Port:  qt4-mac      |
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Comment (by RJVB):

 @jjstickel: could you please try with the new kapplication raster patch I
 pasted (inline) into the PR (https://github.com/macports/macports-
 ports/pull/3022#issuecomment-441384590)? This should

 - prevent glitches when you don't change anything w.r.t. your current
 config (assuming you picked a graphics system via qtconfig)
 - revert the glitches when you select "(unset)" in qtconfig

 For anyone not following discussion on the PR: my initial proposal
 apparently caused crashing with more than just the incompatible styles
 that we identified. This version gives users the choice to stick with the
 forced raster mode as it was always imposed by port:kdelibs4 (and keep
 using pure Qt apps without imposing a graphics system choice). Or they can
 impose a choice via qtconfig.

-- 
Ticket URL: <https://trac.macports.org/ticket/57577#comment:23>
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