ash: Update launcher overflow chevron.

ash/launcher/overflow_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 "ash/launcher/overflow_button.h"
+
+#include "grit/ash_strings.h"
+#include "grit/ui_resources.h"
+#include "third_party/skia/include/core/SkPaint.h"
+#include "third_party/skia/include/core/SkPath.h"
+#include "ui/base/animation/throb_animation.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "ui/base/resource/resource_bundle.h"
+#include "ui/gfx/canvas.h"
+#include "ui/gfx/skia_util.h"
+#include "ui/gfx/transform.h"
+
+namespace ash {
+namespace internal {
+
+namespace {
+
+const int kButtonHoverAlpha = 150;
+
+const int kButtonCornerRadius = 2;
+
+const int kButtonHoverSize = 28;
+
+void RotateCounterclockwise(ui::Transform* transform) {
+  transform->matrix().set3x3(0, -1, 0,
+                             1,  0, 0,
+                             0,  0, 1);
+}
+
+void RotateClockwise(ui::Transform* transform) {
+  transform->matrix().set3x3( 0, 1, 0,
+                             -1, 0, 0,
+                              0, 0, 1);
+}
+
+}  // namesapce
+
+OverflowButton::OverflowButton(views::ButtonListener* listener)
+    : CustomButton(listener),
+      alignment_(SHELF_ALIGNMENT_BOTTOM),
+      image_(NULL) {
+  ResourceBundle& rb = ResourceBundle::GetSharedInstance();
+  image_ = rb.GetImageNamed(IDR_AURA_LAUNCHER_OVERFLOW).ToImageSkia();
+
+  set_accessibility_focusable(true);
+  SetAccessibleName(
+      l10n_util::GetStringUTF16(IDS_AURA_LAUNCHER_OVERFLOW_NAME));
+}
+
+
+OverflowButton::~OverflowButton() {
+}
+
+void OverflowButton::SetShelfAlignment(ShelfAlignment alignment) {
+  if (alignment_ == alignment)
+    return;
+
+  alignment_ = alignment;
+  SchedulePaint();
+}
+
+void OverflowButton::PaintBackground(gfx::Canvas* canvas, int alpha) {
+  gfx::Rect rect(GetContentsBounds());
+  rect = rect.Center(gfx::Size(kButtonHoverSize, kButtonHoverSize));
+
+  SkPaint paint;
+  paint.setAntiAlias(true);
+  paint.setStyle(SkPaint::kFill_Style);
+  paint.setColor(SkColorSetARGB(
+      kButtonHoverAlpha * hover_animation_->GetCurrentValue(),
+      0, 0, 0));
+
+  const SkScalar radius = SkIntToScalar(kButtonCornerRadius);
+  SkPath path;
+  path.addRoundRect(gfx::RectToSkRect(rect), radius, radius);
+  canvas->DrawPath(path, paint);
+}
+
+void OverflowButton::OnPaint(gfx::Canvas* canvas) {
+  if (hover_animation_->is_animating()) {
+    PaintBackground(
+        canvas,
+        kButtonHoverAlpha * hover_animation_->GetCurrentValue());
+  } else if (state() == BS_HOT || state() == BS_PUSHED) {
+    PaintBackground(canvas, kButtonHoverAlpha);
+  }
+
+  ui::Transform transform;
+
+  switch (alignment_) {
+    case SHELF_ALIGNMENT_BOTTOM:
+      // Shift 1 pixel left to align with overflow bubble tip.
+      transform.ConcatTranslate(-1, 0);
+      break;
+    case SHELF_ALIGNMENT_LEFT:
+      RotateClockwise(&transform);
+      transform.ConcatTranslate(width(), -1);
+      break;
+    case SHELF_ALIGNMENT_RIGHT:
+      RotateCounterclockwise(&transform);
+      transform.ConcatTranslate(0, height());
+      break;
+  }
+
+  canvas->Save();
+  canvas->Transform(transform);
+
+  gfx::Rect rect(GetContentsBounds());
+  canvas->DrawImageInt(*image_,
+                       rect.x() + (rect.width() - image_->width()) / 2,
+                       rect.y() + (rect.height() - image_->height()) / 2);
+
+  canvas->Restore();
+}
+
+}  // namespace internal
+}  // namespace ash