[Mac] Create HyperlinkButtonCell and make the "Get themes" button an instance

chrome/browser/cocoa/hyperlink_button_cell.mm

+// Copyright (c) 2009 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.
+
+#import "chrome/browser/cocoa/hyperlink_button_cell.h"
+
+@interface HyperlinkButtonCell (Private)
+- (NSDictionary*)linkAttributres;
+- (void)customizeButtonCell;
+@end
+
+@implementation HyperlinkButtonCell
+@dynamic textColor;
+
+// Designated initializer.
+- (id)init {
+  if ((self = [super init])) {
+    [self customizeButtonCell];
+  }
+  return self;
+}
+
+// Initializer called when the cell is loaded from the NIB.
+- (id)initWithCoder:(NSCoder*)aDecoder {
+  if ((self = [super initWithCoder:aDecoder])) {
+    [self customizeButtonCell];
+  }
+  return self;
+}
+
+// Initializer for code-based creation.
+- (id)initTextCell:(NSString*)title {
+  if ((self = [super initTextCell:title])) {
+    [self customizeButtonCell];
+  }
+  return self;
+}
+
+// Because an NSButtonCell has multiple initializers, this method performs the
+// common cell customization code.
+- (void)customizeButtonCell {
+  [self setBordered:NO];
+  [self setTextColor:[NSColor blueColor]];
+
+  CGFloat fontSize = [NSFont systemFontSizeForControlSize:[self controlSize]];
+  NSFont* font = [NSFont controlContentFontOfSize:fontSize];
+  [self setFont:font];
+
+  // Do not change button appearance when we are pushed.
+  // TODO(rsesek): Change text color to red?
+  [self setHighlightsBy:NSNoCellMask];
+
+  // We need to set this so that we can override |-mouseEntered:| and
+  // |-mouseExited:| to change the cursor style on hover states.
+  [self setShowsBorderOnlyWhileMouseInside:YES];
+}
+
+// Creates the NSDictionary of attributes for the attributed string.
+- (NSDictionary*)linkAttributes {
+  NSUInteger underlineMask = NSUnderlinePatternSolid | NSUnderlineStyleSingle;
+  NSMutableParagraphStyle* paragraphStyle =
+    [[NSParagraphStyle defaultParagraphStyle] mutableCopy];
+  [paragraphStyle setAlignment:[self alignment]];
+
+  return [NSDictionary dictionaryWithObjectsAndKeys:
+      [self textColor], NSForegroundColorAttributeName,
+      [NSNumber numberWithInt:underlineMask], NSUnderlineStyleAttributeName,
+      [self font], NSFontAttributeName,
+      [NSCursor pointingHandCursor], NSCursorAttributeName,
+      paragraphStyle, NSParagraphStyleAttributeName,
+      nil
+  ];
+}
+
+// Override the drawing point for the cell so that the custom style attributes
+// can always be applied.
+- (NSRect)drawTitle:(NSAttributedString*)title
+          withFrame:(NSRect)frame
+             inView:(NSView*)controlView {
+  NSAttributedString* attrString =
+      [[NSAttributedString alloc] initWithString:[title string]
+                                      attributes:[self linkAttributes]];
+  [attrString autorelease];
+  return [super drawTitle:attrString withFrame:frame inView:controlView];
+}
+
+// Override the default behavior to draw the border. Instead, change the cursor.
+- (void)mouseEntered:(NSEvent*)event {
+  [[NSCursor pointingHandCursor] push];
+}
+
+- (void)mouseExited:(NSEvent*)event {
+  [NSCursor pop];
+}
+
+// Setters and getters.
+- (NSColor*)textColor {
+  return textColor_.get();
+}
+
+- (void)setTextColor:(NSColor*)color {
+  textColor_.reset(color);
+}
+
+@end