frontend/ttlineedit.cpp

   1 // ttlineedit.cpp
   2
   3 // Copyright (C) 2012-2022 by Werner Lemberg.
   4 //
   5 // This file is part of the ttfautohint library, and may only be used,
   6 // modified, and distributed under the terms given in `COPYING'.  By
   7 // continuing to use, modify, or distribute this file you indicate that you
   8 // have read `COPYING' and understand and accept it fully.
   9 //
  10 // The file `COPYING' mentioned in the previous paragraph is distributed
  11 // with the ttfautohint library.
  12
  13
  14 // Derived class `Tooltip_Line_Edit' is QLineEdit that displays a tooltip
  15 // if the data in the field is wider than the field width.
  16
  17 #include <config.h>
  18
  19 #include "ttlineedit.h"
  20
  21 Tooltip_Line_Edit::Tooltip_Line_Edit(QWidget* parent)
  22 : QLineEdit(parent)
  23 {
  24   connect(this, SIGNAL(textChanged(QString)),
  25           this, SLOT(change_tooltip(QString)));
  26 }
  27
  28
  29 void Tooltip_Line_Edit::change_tooltip(QString tip)
  30 {
  31   QFont font = this->font();
  32   QFontMetrics metrics(font);
  33
  34   // get the (sum of the) left and right borders; this is a bit tricky
  35   // since Qt doesn't have methods to directly access those margin values
  36   int line_minwidth = minimumSizeHint().width();
  37   int char_maxwidth = metrics.maxWidth();
  38   int border = line_minwidth - char_maxwidth;
  39
  40   int linewidth = this->width();
  41   int textwidth = metrics.width(tip);
  42
  43   if (textwidth > linewidth - border)
  44     this->setToolTip(tip);
  45   else
  46     this->setToolTip("");
  47 }
  48
  49 // end of ttlineedit.cpp