Added text line limits to collapsed and expanded notifications.

ui/message_center/views/bounded_label.h

+// 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.
+
+#ifndef UI_MESSAGE_CENTER_BOUNDED_LABEL_H_
+#define UI_MESSAGE_CENTER_BOUNDED_LABEL_H_
+
+#include "testing/gtest/include/gtest/gtest_prod.h"
+#include "ui/message_center/message_center_export.h"
+#include "ui/views/controls/label.h"
+
+namespace message_center {
+
+// BoundedLabels display text up to a maximum number of lines, with ellipsis at
+// the end of the last line for any omitted text. The font, text, multiline
+// behavior, character break behavior, elide behavior, and focus border of
+// instances of this views::Label subclass cannot be changed, so the following
+// views::Label methods should never be called with instances of this class:
+//
+//   SetFont()
+//   SetText()
+//   SetMultiLine()
+//   SetAllowCharacterBreak()
+//   SetElideBehavior()
+//   SetHasFocusBorder()
+//
+class MESSAGE_CENTER_EXPORT BoundedLabel : public views::Label {
+ public:
+  BoundedLabel(string16 text, size_t max_lines);
+  BoundedLabel(string16 text, gfx::Font font, size_t max_lines);
+  virtual ~BoundedLabel();
+
+  void SetMaxLines(size_t lines);
+  size_t GetMaxLines();
+  size_t GetPreferredLines();
+
+  virtual int GetHeightForWidth(int width) const OVERRIDE;
+
+ protected:
+  // Overridden from views::Label.
+  virtual gfx::Size GetTextSize() const OVERRIDE;
+  virtual void OnBoundsChanged(const gfx::Rect& previous_bounds) OVERRIDE;
+  virtual void PaintText(gfx::Canvas* canvas,
+                         const string16& text,
+                         const gfx::Rect& text_bounds,
+                         int flags) OVERRIDE;
+
+ private:
+  friend class BoundedLabelTest;
+
+  void Init(size_t max_lines);
+  int GetTextFlags() const;
+  std::vector<string16> SplitLines(int width, size_t max_lines) const;
+
+  size_t max_lines_;
+  size_t preferred_lines_;
+  bool is_preferred_lines_valid_;
+  mutable gfx::Size text_size_;
+  mutable bool is_text_size_valid_;
+
+  DISALLOW_COPY_AND_ASSIGN(BoundedLabel);
+};
+
+}  // namespace message_center
+
+#endif // UI_MESSAGE_CENTER_BOUNDED_LABEL_H_