Allow TextButton derivatives to override drawing of certain parts.

ui/views/controls/button/text_button.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/views/controls/button/text_button.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "grit/ui_resources.h"
@@ skipping 427 matching lines @@
   focus_painter_ = focus_painter.Pass();
 }
 
 void TextButtonBase::PaintButton(gfx::Canvas* canvas, PaintButtonMode mode) {
   if (mode == PB_NORMAL) {
     OnPaintBackground(canvas);
     OnPaintBorder(canvas);
     Painter::PaintFocusPainter(this, canvas, focus_painter_.get());
   }
 
+  OnPaintText(canvas, mode);
+}
+
+void TextButtonBase::OnPaintText(gfx::Canvas* canvas, PaintButtonMode mode) {
   gfx::Rect text_bounds(GetTextBounds());
   if (text_bounds.width() > 0) {
     // Because the text button can (at times) draw multiple elements on the
     // canvas, we can not mirror the button by simply flipping the canvas as
     // doing this will mirror the text itself. Flipping the canvas will also
     // make the icons look wrong because icons are almost always represented as
     // direction-insensitive images and such images should never be flipped
     // horizontally.
     //
     // Due to the above, we must perform the flipping manually for RTL UIs.
@@ skipping 165 matching lines @@
   prefsize.set_height(std::max(prefsize.height(), min_height_));
 
   return prefsize;
 }
 
 void TextButton::PaintButton(gfx::Canvas* canvas, PaintButtonMode mode) {
   if (full_justification_ && icon_placement_ == ICON_ON_LEFT)
       set_alignment(ALIGN_RIGHT);
 
   TextButtonBase::PaintButton(canvas, mode);
+  OnPaintIcon(canvas, mode);
+}
 
+void TextButton::OnPaintIcon(gfx::Canvas* canvas, PaintButtonMode mode) {
   const gfx::ImageSkia& icon = GetImageToPaint();
 
   if (icon.width() > 0) {
     gfx::Rect text_bounds = GetTextBounds();
     int icon_x = 0;
     int spacing = text_.empty() ? 0 : icon_text_spacing_;
     gfx::Insets insets = GetInsets();
     switch (icon_placement_) {
       case ICON_ON_LEFT:
         icon_x = full_justification_ ? insets.left()
@@ skipping 68 matching lines @@
   if (show_multiple_icon_states_) {
     if (has_hover_icon_ && (state() == STATE_HOVERED))
       return icon_hover_;
     if (has_pushed_icon_ && (state() == STATE_PRESSED))
       return icon_pushed_;
   }
   return icon_;
 }
 
 }  // namespace views