Implement an indeterminate progress-bar

ui/message_center/views/notification_progress_bar.cc

+// Copyright 2015 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/message_center/views/notification_progress_bar.h"
+
+#include "third_party/skia/include/core/SkPaint.h"
+#include "third_party/skia/include/core/SkPath.h"
+#include "ui/gfx/animation/linear_animation.h"
+#include "ui/gfx/canvas.h"
+#include "ui/gfx/geometry/size.h"
+#include "ui/gfx/skia_util.h"
+#include "ui/gfx/text_elider.h"
+#include "ui/message_center/message_center_style.h"
+
+namespace {
+
+// Dimensions.
+const int kProgressBarWidth = message_center::kNotificationWidth -
+    message_center::kTextLeftPadding - message_center::kTextRightPadding;
+
+const int kAnimationFrameRateHz = 60;
+
+const int kAnimationDuration = 2000;  // In millisecond
+
+} // namespace
+
+namespace message_center {
+
+// NotificationProgressBar /////////////////////////////////////////////////////
+
+NotificationProgressBar::NotificationProgressBar() {
+}
+
+NotificationProgressBar::~NotificationProgressBar() {
+  if (indeterminate_bar_animation_)
+    indeterminate_bar_animation_->Stop();  // Just in case
+}
+
+gfx::Size NotificationProgressBar::GetPreferredSize() const {
+  gfx::Size pref_size(kProgressBarWidth, message_center::kProgressBarThickness);
+  gfx::Insets insets = GetInsets();
+  pref_size.Enlarge(insets.width(), insets.height());
+  return pref_size;
+}
+
+void NotificationProgressBar::SetIndeterminate(bool is_indeterminate) {
+  if (is_indeterminate) {
+    if (!indeterminate_bar_animation_) {
+      // Initialize the animation object.
+      indeterminate_bar_animation_.reset(
+          new gfx::LinearAnimation(kAnimationFrameRateHz, this));
+      indeterminate_bar_animation_->SetDuration(kAnimationDuration);
+    }
+    indeterminate_bar_animation_->Start();
+  } else if (indeterminate_bar_animation_) {
+    indeterminate_bar_animation_->Stop();
+  }
+  SchedulePaint();
+}
+
+void NotificationProgressBar::OnPaint(gfx::Canvas* canvas) {
+  gfx::Rect content_bounds = GetContentsBounds();
+
+  // Draw background.
+  SkPath background_path;
+  background_path.addRoundRect(gfx::RectToSkRect(content_bounds),
+                               message_center::kProgressBarCornerRadius,
+                               message_center::kProgressBarCornerRadius);
+  SkPaint background_paint;
+  background_paint.setStyle(SkPaint::kFill_Style);
+  background_paint.setFlags(SkPaint::kAntiAlias_Flag);
+  background_paint.setColor(message_center::kProgressBarBackgroundColor);
+  canvas->DrawPath(background_path, background_paint);
+
+  // Draw slice.
+  SkPath slice_path;
+  if (indeterminate_bar_animation_ &&
+      indeterminate_bar_animation_->is_animating()) {
+    double time = indeterminate_bar_animation_->GetCurrentValue();
+
+    double bar1_left;
+    double bar1_width;
+    double bar2_left;
+    double bar2_width;
+    if (time < 0.25) {
+      bar1_left = time / 2;
+      bar1_width = time * 1.5;
+      bar2_left = 0;
+      bar2_width = 0;

[Jun Mukai, 2015/11/16 08:29:31]

Those values look exactly same as time < 0.5. What's the point of time < 0.25?

[yoshiki, 2015/11/24 16:39:24]

The bar2 is hidden if time < 0.5. It's intended.

[Jun Mukai, 2015/11/24 17:51:11]

You don't address my question. I said this line 87-90 looks exactly same as line
92-95, therefore you can remove this 'if (time < 0.25) { ... } else'. Am I
missing something?

[yoshiki, 2015/11/25 15:14:28]

Ah, I misunderstood. Your're right, and they were same. I combined them.

+    } else if (time < 0.5) {
+      bar1_left = time / 2;
+      bar1_width = time * 1.5;
+      bar2_left = 0;
+      bar2_width = 0;
+    } else if (time < 0.75) {
+      bar1_left = time * 3 - 1.25;
+      bar1_width = 0.75 - (time - 0.5)  * 3;
+      bar2_left = 0;
+      bar2_width = time - 0.5;
+    } else {
+      bar1_left = 1;
+      bar1_width = 0;
+      bar2_left = (time - 0.75) * 4;
+      bar2_width = 0.25 - (time - 0.75);
+    }
+
+    int bar1_x = static_cast<int>(content_bounds.width() * bar1_left);
+    int bar1_w =
+        std::min(static_cast<int>(content_bounds.width() * bar1_width + 0.5),
+                 content_bounds.width() - bar1_x);
+    int bar2_x = static_cast<int>(content_bounds.width() * bar2_left);
+    int bar2_w =
+        std::min(static_cast<int>(content_bounds.width() * bar2_width + 0.5),
+                 content_bounds.width() - bar2_x);
+
+
+    gfx::Rect slice_bounds = content_bounds;
+    slice_bounds.set_x(content_bounds.x() + bar1_x);
+    slice_bounds.set_width(bar1_w);
+    slice_path.addRoundRect(gfx::RectToSkRect(slice_bounds),
+                            message_center::kProgressBarCornerRadius,
+                            message_center::kProgressBarCornerRadius);
+    slice_bounds.set_x(content_bounds.x() + bar2_x);
+    slice_bounds.set_width(bar2_w);
+    slice_path.addRoundRect(gfx::RectToSkRect(slice_bounds),
+                            message_center::kProgressBarCornerRadius,
+                            message_center::kProgressBarCornerRadius);
+  } else {
+    const int slice_width =
+        static_cast<int>(content_bounds.width() * GetNormalizedValue() + 0.5);
+    if (slice_width < 1)
+      return;
+
+    gfx::Rect slice_bounds = content_bounds;
+    slice_bounds.set_width(slice_width);
+    slice_path.addRoundRect(gfx::RectToSkRect(slice_bounds),
+                            message_center::kProgressBarCornerRadius,
+                            message_center::kProgressBarCornerRadius);
+  }
+  SkPaint slice_paint;
+  slice_paint.setStyle(SkPaint::kFill_Style);
+  slice_paint.setFlags(SkPaint::kAntiAlias_Flag);
+  slice_paint.setColor(message_center::kProgressBarSliceColor);
+  canvas->DrawPath(slice_path, slice_paint);
+}
+
+void NotificationProgressBar::AnimationProgressed(
+    const gfx::Animation* animation) {
+  if (animation == indeterminate_bar_animation_.get()) {
+    DCHECK(indeterminate_bar_animation_);
+    SchedulePaint();
+  }
+}
+
+void NotificationProgressBar::AnimationEnded(const gfx::Animation* animation) {
+  // Restarts animation.
+  if (animation == indeterminate_bar_animation_.get()) {
+    DCHECK(indeterminate_bar_animation_);
+    indeterminate_bar_animation_->Start();
+  }
+}
+
+}  // namespace message_center