Better integration between View and LayoutManager.

Views now rely on layout manager for both preferred and minimum size,
and layout managers can be notified when a view's layout is invalidated.

Change-Id: I189eab4bf1ab4369db0d7ca5391b432ac3424fcc
Reviewed-on: https://chromium-review.googlesource.com/c/1351967
Commit-Queue: Dana Fried <dfried@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#611507}

chrome/browser/ui/views/frame/browser_view.cc

@@ -2275,7 +2275,7 @@ int BrowserView::NonClientHitTest(const gfx::Point& point) {
 }
 
 gfx::Size BrowserView::GetMinimumSize() const {
-  return GetBrowserViewLayout()->GetMinimumSize();
+  return GetBrowserViewLayout()->GetMinimumSize(this);
 }
 
 ///////////////////////////////////////////////////////////////////////////////

chrome/browser/ui/views/frame/browser_view_layout.cc

@@ -4,6 +4,8 @@
 
 #include "chrome/browser/ui/views/frame/browser_view_layout.h"
 
+#include <algorithm>
+
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "build/build_config.h"
@@ -168,7 +170,7 @@ WebContentsModalDialogHost*
   return dialog_host_.get();
 }
 
-gfx::Size BrowserViewLayout::GetMinimumSize() {
+gfx::Size BrowserViewLayout::GetMinimumSize(const views::View* host) const {
   gfx::Size tabstrip_size(
       browser()->SupportsWindowFeature(Browser::FEATURE_TABSTRIP) ?
       tab_strip_->GetMinimumSize() : gfx::Size());
@@ -184,7 +186,7 @@ gfx::Size BrowserViewLayout::GetMinimumSize() {
     bookmark_bar_size.Enlarge(0, -bookmark_bar_->GetToolbarOverlap());
   }
   gfx::Size infobar_container_size(infobar_container_->GetMinimumSize());
-  // TODO: Adjust the minimum height for the find bar.
+  // TODO(pkotwicz): Adjust the minimum height for the find bar.
 
   gfx::Size contents_size(contents_container_->GetMinimumSize());
   // Prevent having a 0x0 sized-contents as this can allow the window to be

chrome/browser/ui/views/frame/browser_view_layout.h

@@ -28,6 +28,7 @@ class Size;
 
 namespace views {
 class ClientView;
+class View;
 }
 
 namespace web_modal {
@@ -66,9 +67,6 @@ class BrowserViewLayout : public views::LayoutManager {
 
   web_modal::WebContentsModalDialogHost* GetWebContentsModalDialogHost();
 
-  // Returns the minimum size of the browser view.
-  gfx::Size GetMinimumSize();
-
   // Returns the bounding box, in widget coordinates,  for the find bar.
   gfx::Rect GetFindBarBoundingBox() const;
 
@@ -80,6 +78,7 @@ class BrowserViewLayout : public views::LayoutManager {
 
   // views::LayoutManager overrides:
   void Layout(views::View* host) override;
+  gfx::Size GetMinimumSize(const views::View* host) const override;
   gfx::Size GetPreferredSize(const views::View* host) const override;
 
   // Returns true if an infobar is showing.
@@ -92,6 +91,7 @@ class BrowserViewLayout : public views::LayoutManager {
   class WebContentsModalDialogHostViews;
 
   Browser* browser() { return browser_; }
+  const Browser* browser() const { return browser_; }
 
   // Layout the following controls, starting at |top|, returns the coordinate
   // of the bottom of the control, for laying out the next control.

chrome/browser/ui/views/frame/opaque_browser_frame_view.cc

@@ -4,6 +4,9 @@
 
 #include "chrome/browser/ui/views/frame/opaque_browser_frame_view.h"
 
+#include <algorithm>
+#include <utility>
+
 #include "build/build_config.h"
 #include "build/buildflag.h"
 #include "chrome/browser/themes/theme_properties.h"
@@ -213,7 +216,7 @@ void OpaqueBrowserFrameView::UpdateThrobber(bool running) {
 }
 
 gfx::Size OpaqueBrowserFrameView::GetMinimumSize() const {
-  return layout_->GetMinimumSize(width());
+  return layout_->GetMinimumSize(this);
 }
 
 ///////////////////////////////////////////////////////////////////////////////

chrome/browser/ui/views/frame/opaque_browser_frame_view_layout.cc

@@ -4,6 +4,10 @@
 
 #include "chrome/browser/ui/views/frame/opaque_browser_frame_view_layout.h"
 
+#include <algorithm>
+#include <string>
+#include <vector>
+
 #include "base/command_line.h"
 #include "base/containers/adapters.h"
 #include "base/stl_util.h"
@@ -93,7 +97,7 @@ gfx::Rect OpaqueBrowserFrameViewLayout::GetBoundsForTabStrip(
 }
 
 gfx::Size OpaqueBrowserFrameViewLayout::GetMinimumSize(
-    int available_width) const {
+    const views::View* host) const {
   gfx::Size min_size = delegate_->GetBrowserViewMinimumSize();
   int border_thickness = FrameBorderThickness(false);
   min_size.Enlarge(2 * border_thickness,

chrome/browser/ui/views/frame/opaque_browser_frame_view_layout.h

@@ -5,6 +5,8 @@
 #ifndef CHROME_BROWSER_UI_VIEWS_FRAME_OPAQUE_BROWSER_FRAME_VIEW_LAYOUT_H_
 #define CHROME_BROWSER_UI_VIEWS_FRAME_OPAQUE_BROWSER_FRAME_VIEW_LAYOUT_H_
 
+#include <vector>
+
 #include "base/macros.h"
 #include "chrome/browser/ui/frame_button_display_types.h"
 #include "chrome/browser/ui/views/frame/opaque_browser_frame_view.h"
@@ -52,8 +54,6 @@ class OpaqueBrowserFrameViewLayout : public views::LayoutManager {
   gfx::Rect GetBoundsForTabStrip(const gfx::Size& tabstrip_preferred_size,
                                  int total_width) const;
 
-  gfx::Size GetMinimumSize(int available_width) const;
-
   // Returns the bounds of the window required to display the content area at
   // the specified bounds.
   gfx::Rect GetWindowBoundsForClientBounds(
@@ -128,6 +128,11 @@ class OpaqueBrowserFrameViewLayout : public views::LayoutManager {
   // Returns the extra thickness of the area above the tabs.
   int GetNonClientRestoredExtraThickness() const;
 
+  // views::LayoutManager:
+  // Called explicitly from OpaqueBrowserFrameView so we can't group it with
+  // the other overrides.
+  gfx::Size GetMinimumSize(const views::View* host) const override;
+
  protected:
   // Whether a specific button should be inserted on the leading or trailing
   // side.

chrome/browser/ui/views/frame/opaque_browser_frame_view_layout_unittest.cc

@@ -4,6 +4,10 @@
 
 #include "chrome/browser/ui/views/frame/opaque_browser_frame_view_layout.h"
 
+#include <memory>
+#include <utility>
+#include <vector>
+
 #include "base/command_line.h"
 #include "base/macros.h"
 #include "base/strings/utf_string_conversions.h"
@@ -266,7 +270,7 @@ class OpaqueBrowserFrameViewLayoutTest : public ChromeViewsTestBase {
     gfx::Size browser_view_min_size(delegate_->GetBrowserViewMinimumSize());
     const int min_width =
         browser_view_min_size.width() + tabstrip_min_size.width() + spacing;
-    gfx::Size min_size(layout_manager_->GetMinimumSize(kWindowWidth));
+    gfx::Size min_size(layout_manager_->GetMinimumSize(root_view_));
     EXPECT_EQ(min_width, min_size.width());
     int restored_border_height =
         2 * OpaqueBrowserFrameViewLayout::kFrameBorderThickness +

ui/views/layout/layout_manager.cc

@@ -14,6 +14,20 @@ LayoutManager::~LayoutManager() {
 void LayoutManager::Installed(View* host) {
 }
 
+void LayoutManager::InvalidateLayout() {}
+
+gfx::Size LayoutManager::GetMinimumSize(const View* host) const {
+  // Fall back to using preferred size if no minimum size calculation is
+  // available (e.g. legacy layout managers).
+  //
+  // Ideally we'd just call GetPreferredSize() on ourselves here, but because
+  // some legacy views with layout managers override GetPreferredSize(), we need
+  // to call GetPreferredSize() on the host view instead. The default
+  // views::View behavior will be to call GetPreferredSize() on this layout
+  // manager, so the fallback behavior in all other cases is as expected.
+  return host->GetPreferredSize();
+}
+
 int LayoutManager::GetPreferredHeightForWidth(const View* host,
                                               int width) const {
   return GetPreferredSize(host).height();

ui/views/layout/layout_manager.h

@@ -34,16 +34,27 @@ class VIEWS_EXPORT LayoutManager {
   // Notification that this LayoutManager has been installed on |host|.
   virtual void Installed(View* host);
 
+  // For layout managers that can cache layout data, it's useful to let the
+  // layout manager know that its current layout might not be valid.
+  // TODO(dfried): consider if we should include some default behavior (like a
+  // rolling layout counter).
+  virtual void InvalidateLayout();
+
   // Called by View::Layout() to position and size the children of |host|.
   // Generally this queries |host| for its size and positions and sizes the
   // children in a LayoutManager specific way.
   virtual void Layout(View* host) = 0;
 
-  // Return the preferred size, which is typically the size needed to give each
+  // Returns the preferred size, which is typically the size needed to give each
   // child of |host| its preferred size. Generally this is calculated using the
   // View::CalculatePreferredSize() on each of the children of |host|.
   virtual gfx::Size GetPreferredSize(const View* host) const = 0;
 
+  // Returns the minimum size, which defaults to the preferred size. Layout
+  // managers with the ability to collapse or hide child views may override this
+  // behavior.
+  virtual gfx::Size GetMinimumSize(const View* host) const;
+
   // Return the preferred height for a particular width. Generally this is
   // calculated using View::GetHeightForWidth() or
   // View::CalculatePreferredSize() on each of the children of |host|. Override

ui/views/view.cc

@@ -423,6 +423,9 @@ void View::SizeToPreferredSize() {
 }
 
 gfx::Size View::GetMinimumSize() const {
+  if (layout_manager_)
+    return layout_manager_->GetMinimumSize(this);
+
   return GetPreferredSize();
 }
 
@@ -431,7 +434,7 @@ gfx::Size View::GetMaximumSize() const {
 }
 
 int View::GetHeightForWidth(int w) const {
-  if (layout_manager_.get())
+  if (layout_manager_)
     return layout_manager_->GetPreferredHeightForWidth(this, w);
   return GetPreferredSize().height();
 }
@@ -586,7 +589,7 @@ void View::Layout() {
   needs_layout_ = false;
 
   // If we have a layout manager, let it handle the layout for us.
-  if (layout_manager_.get())
+  if (layout_manager_)
     layout_manager_->Layout(this);
 
   // Make sure to propagate the Layout() call to any children that haven't
@@ -609,6 +612,9 @@ void View::InvalidateLayout() {
   // Always invalidate up. This is needed to handle the case of us already being
   // valid, but not our parent.
   needs_layout_ = true;
+  if (layout_manager_)
+    layout_manager_->InvalidateLayout();
+
   if (parent_)
     parent_->InvalidateLayout();
 }
@@ -1496,7 +1502,7 @@ bool View::HasObserver(const ViewObserver* observer) const {
 // Size and disposition --------------------------------------------------------
 
 gfx::Size View::CalculatePreferredSize() const {
-  if (layout_manager_.get())
+  if (layout_manager_)
     return layout_manager_->GetPreferredSize(this);
   return gfx::Size();
 }