Broke out layout metric information from ViewsDelegate to LayoutProvider

chrome/browser/ui/views/harmony/chrome_views_layout_delegate.h

+// Copyright 2016 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 CHROME_BROWSER_UI_VIEWS_HARMONY_CHROME_VIEWS_LAYOUT_DELEGATE_H_
+#define CHROME_BROWSER_UI_VIEWS_HARMONY_CHROME_VIEWS_LAYOUT_DELEGATE_H_
+
+#include <memory>
+
+#include "base/macros.h"
+#include "ui/gfx/geometry/insets.h"
+#include "ui/views/layout/grid_layout.h"
+#include "ui/views/layout/views_layout_delegate.h"
+
+enum class ChromeInsetsMetric {

[Peter Kasting, 2017/04/04 02:08:54]

Looks like you stuck with the enum class route.  Did you want to come to
agreement on that here or do a separate email thread about it?

[kylix_rd, 2017/04/04 20:28:23]

Either way. I prefer to use an enum class since it is properly scoped and
doesn't "infect" the outer namespace with extra symbols. While this is a slight
departure from the other technique, it is the same in spirit. It is also
type-safe with compile-time checking.

There isn't the likelihood of another level of inheritance (aside from the
harmony specialization), so this enum can be considered "sealed".

[Peter Kasting, 2017/04/05 19:30:10]

Let's do it as a separate thread for clarity.  Why don't you send something to
sky/tapted/me and say I asked that we all get on the same page regarding what to
do both here and elsewhere.

+  // The margins that should be applied around a bubble dialog.

[Peter Kasting, 2017/04/04 02:08:53]

Nit: Even if we stick with the enum route, don't copy the comments on these from
the base class -- just have a commentless top section that "mirrors over" the
base values, then save comments for the new cases.

[kylix_rd, 2017/04/04 20:28:23]

Done.

+  BUBBLE_DIALOG = views::InsetsMetric::BUBBLE_DIALOG,
+  // The insets that should be applied around a DialogClientView. Note that
+  // the top inset is used for the distance between the buttons and the
+  // DialogClientView's content view.
+  DIALOG_BUTTON = views::InsetsMetric::DIALOG_BUTTON,
+  // The insets that should be applied around a dialog's frame view.
+  DIALOG_FRAME_VIEW = views::InsetsMetric::DIALOG_FRAME_VIEW,
+  // Padding to add to vector image buttons to increase their click and touch
+  // target size.
+  VECTOR_IMAGE_BUTTON = views::InsetsMetric::VECTOR_IMAGE_BUTTON,
+  // The insets applied around a content panel

[Peter Kasting, 2017/04/04 02:08:54]

Nit: Trailing period.

[kylix_rd, 2017/04/04 20:28:23]

Done.

+  PANEL_LAYOUT,
+};
+
+enum class ChromeDistanceMetric {
+  // The default padding to add on each side of a button's label.
+  BUTTON_HORIZONTAL_PADDING = views::DistanceMetric::BUTTON_HORIZONTAL_PADDING,
+  // The distance between a dialog's edge and the close button in the upper
+  // trailing corner.
+  CLOSE_BUTTON_MARGIN = views::DistanceMetric::CLOSE_BUTTON_MARGIN,
+  // The default minimum width of a dialog button.
+  DIALOG_BUTTON_MINIMUM_WIDTH =
+      views::DistanceMetric::DIALOG_BUTTON_MINIMUM_WIDTH,
+  // The spacing between a pair of related horizontal buttons, used for
+  // dialog layout.
+  RELATED_BUTTON_HORIZONTAL = views::DistanceMetric::RELATED_BUTTON_HORIZONTAL,
+  // Horizontal spacing between controls that are logically related.
+  RELATED_CONTROL_HORIZONTAL =
+      views::DistanceMetric::RELATED_CONTROL_HORIZONTAL,
+  // The spacing between a pair of related vertical controls, used for
+  // dialog layout.
+  RELATED_CONTROL_VERTICAL = views::DistanceMetric::RELATED_CONTROL_VERTICAL,
+  // Margin between the edge of a dialog and the left, right, or bottom of a
+  // contained button.
+  DIALOG_BUTTON_MARGIN,
+  // Spacing between a dialog button and the content above it.
+  DIALOG_BUTTON_TOP,
+  // Horizontal or vertical margin between the edge of a panel and the
+  // contained content.
+  PANEL_CONTENT_MARGIN,
+  // The maximum width a button can have and still influence the sizes of
+  // other linked buttons.  This allows short buttons to have linked widths
+  // without long buttons making things overly wide.
+  BUTTON_MAX_LINKABLE_WIDTH,
+  // Default minimum width of a button.
+  BUTTON_MINIMUM_WIDTH,
+  // Smaller horizontal spacing between other controls that are logically
+  // related.
+  RELATED_CONTROL_HORIZONTAL_SMALL,
+  // Smaller vertical spacing between controls that are logically related.
+  RELATED_CONTROL_VERTICAL_SMALL,
+  // Horizontal spacing between an item such as an icon or checkbox and a
+  // label related to it.
+  RELATED_LABEL_HORIZONTAL,
+  // Horizontal indent of a subsection relative to related items above, e.g.
+  // checkboxes below explanatory text/headings.
+  SUBSECTION_HORIZONTAL_INDENT,
+  // Horizontal spacing between controls that are logically unrelated.
+  UNRELATED_CONTROL_HORIZONTAL,
+  // Larger horizontal spacing between unrelated controls.
+  UNRELATED_CONTROL_HORIZONTAL_LARGE,
+  // Vertical spacing between controls that are logically unrelated.
+  UNRELATED_CONTROL_VERTICAL,
+  // Larger vertical spacing between unrelated controls.
+  UNRELATED_CONTROL_VERTICAL_LARGE,
+};
+
+enum class DialogWidth {
+  SMALL,
+  MEDIUM,
+  LARGE,
+};
+
+class ChromeViewsLayoutDelegate : public views::ViewsLayoutDelegate {
+ public:
+  ChromeViewsLayoutDelegate();
+  ~ChromeViewsLayoutDelegate() override;
+
+  static ChromeViewsLayoutDelegate* Get();
+  static std::unique_ptr<views::ViewsLayoutDelegate> CreateLayoutDelegate();
+
+  virtual gfx::Insets GetInsetsMetric(ChromeInsetsMetric metric) const;
+  virtual int GetDistanceMetric(ChromeDistanceMetric metric) const;
+
+  const views::TypographyProvider& GetTypographyProvider() const override;
+
+  // Returns the alignment used for control labels in a GridLayout; for example,
+  // in this GridLayout:
+  //   ---------------------------
+  //   | Label 1      Checkbox 1 |
+  //   | Label 2      Checkbox 2 |
+  //   ---------------------------
+  // This value controls the alignment used for "Label 1" and "Label 2".
+  virtual views::GridLayout::Alignment GetControlLabelGridAlignment() const;
+
+  // Returns whether to use extra padding on dialogs. If this is false, content
+  // Views for dialogs should not insert extra padding at their own edges.
+  virtual bool UseExtraDialogPadding() const;
+
+  // Returns whether to show the icon next to the title text on a dialog.
+  virtual bool ShouldShowWindowIcon() const;
+
+  // DEPRECATED.  Returns whether Harmony mode is enabled.
+  //
+  // Instead of using this, create a generic solution that works for all UI
+  // types, e.g. by adding a new LayoutDistance value that means what you need.
+  //
+  // TODO(pkasting): Fix callers and remove this.
+  virtual bool IsHarmonyMode() const;
+
+  // Returns the preferred width in DIPs for a dialog of the specified |width|.
+  // May return 0 if the dialog has no preferred width.
+  virtual int GetDialogPreferredWidth(DialogWidth width) const;
+
+  int GetDefaultDistanceMetric(views::DistanceMetric metric) const;
+
+ private:
+  gfx::Insets GetInsetsMetric(views::InsetsMetric metric) const override;
+  int GetDistanceMetric(views::DistanceMetric metric) const override;
+
+  DISALLOW_COPY_AND_ASSIGN(ChromeViewsLayoutDelegate);
+};
+
+#endif  // CHROME_BROWSER_UI_VIEWS_HARMONY_CHROME_VIEWS_LAYOUT_DELEGATE_H_