modules/javafx.controls/src/main/java/com/sun/javafx/scene/control/skin/Utils.java

*** 1,7 ****
  /*
!  * Copyright (c) 2011, 2016, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
--- 1,7 ----
  /*
!  * Copyright (c) 2011, 2017, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
*** 144,153 ****
--- 144,198 ----
              layout.setBoundsType(0);
          }
          return layout.getBounds().getHeight();
      }
  
+     public static Point2D computeMnemonicPosition(Font font, String text, int mnemonicIndex, double wrappingWidth,
+                                                   double lineSpacing) {
+         // Input validation
+         if ((font == null) || (text == null) ||
+             (mnemonicIndex < 0) || (mnemonicIndex > text.length())) {
+             return  null;
+         }
+ 
+         // Layout the text with given font, wrapping width and line spacing
+         layout.setContent(text, FontHelper.getNativeFont(font));
+         layout.setWrapWidth((float)wrappingWidth);
+         layout.setLineSpacing((float)lineSpacing);
+ 
+         // The text could be spread over multiple lines
+         // We need to find out on which line the mnemonic character lies
+         int start = 0;
+         int i = 0;
+         int totalLines = layout.getLines().length;
+         while (i < totalLines) {
+             int lineLength =  layout.getLines()[i].getLength();
+ 
+             if ((mnemonicIndex >= start) &&
+                 (mnemonicIndex < (start + lineLength))) {
+                 // mnemonic lies on line 'i'
+                 break;
+             }
+ 
+             start = start + lineLength;
+             i++;
+         }
+ 
+         // Find x and y offsets of mnemonic character position
+         // in line numbered 'i'
+         double lineHeight = layout.getBounds().getHeight() / totalLines;
+         double x = Utils.computeTextWidth(font, text.substring(start, mnemonicIndex), 0 );
+ 
+         double y = (lineHeight * (i+1));
+         // Adjust y offset for linespacing except for the last line.
+         if ((i+1) != totalLines) {
+             y = y - (lineSpacing / 2);
+         }
+ 
+         return new Point2D(x, y);
+     }
+ 
      public static int computeTruncationIndex(Font font, String text, double width) {
          helper.setText(text);
          helper.setFont(font);
          helper.setWrappingWidth(0);
          helper.setLineSpacing(0);