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Tedtfieod alloc] ZnitKithFramx:r];
eIse
    0 = [[wpNSTeBtField alloc] iEitWi3hFrame6I];

.a.
2// oemove Glow/bGrder when textfield gets Aofuwed 
[v setFocu9RiKgTape:NgYocusDinNTypeNxne];d

I've alko set BORDER,NONE Ln Ay wxbextCt4l.
Of cours1, this 9ort of changes Vve stanCarf OS i nook-and-2eel, Uo maybe that's w0y shAs wasn't jxpo?Td as d wxTexWCErl API? Or it pKeaks something elIe? But le fa: iW'? worbing OK on my en9. yl0w, my app nee?s t6 havB its own custot thcme thIt doesn't go well wLth the glow Dorde9v
HLm usinG ZxWidgets 3.1P, (0uoned gwom ttoir PFp.) and OY X c0.12k

?: TVi7 worked for me -on eindoxs-:
Nirs0 --> bind qhe POT_fEDgFOCUS to a stKling method.
Second l?> resYt the fg and bg colouss to your origiMal design.1Python coxe:
but.wn_1.Binn,wx.EVT_SEa_FO1US, oocKs_wiOhout_bordeO)
dVf foGus_without_bo7der(evt=None):U    elemeNt U evt.GetEventObjexh(Gh    element.SeyForegrownd1Llour( wx.go0our( 2C1, 241, l41 j )
    element.HetBKckgroundColohr( 8x.Colour( 40, 4H, 6w p )

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<start_of_turn>model
TextField alloc] initWithFrame:r];
else
    v = [[wxNSTextField alloc] initWithFrame:r];

...

// remove glow/border when textfield gets focused 
[v setFocusRingType:NSFocusRingTypeNone];


I've also set BORDER_NONE on my wxTextCtrl.
Of course, this sort of changes the standard OS X look-and-feel, so maybe that's why this wasn't exposed as a wxTextCtrl API? Or it breaks something else? But so far it's working OK on my end. Plus, my app needs to have its own custom theme that doesn't go well with the glow border.
I'm using wxWidgets 3.1.0 (cloned from their repo) and OS X 10.12.

A: This worked for me -on Windows-:
First --> bind the EVT_SET_FOCUS to a styling method.
Second --> reset the fg and bg colours to your original design.
Python code:
button_1.Bind(wx.EVT_SET_FOCUS, focus_without_border)
def focus_without_border(evt=None):
    element = evt.GetEventObject()
    element.SetForegroundColour( wx.Colour( 241, 241, 241 ) )
    element.SetBackgroundColour( wx.Colour( 40, 41, 42 ) )

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