[win] Ensure the app launcher always comes up on screen.

chrome/browser/ui/views/app_list/app_list_controller_win.cc

Index: chrome/browser/ui/views/app_list/app_list_controller_win.cc
diff --git a/chrome/browser/ui/views/app_list/app_list_controller_win.cc b/chrome/browser/ui/views/app_list/app_list_controller_win.cc
index c9d334dc1268905c01990cebccd1549c037e2df9..498cac3f5516670c4b7663ac54e0e86cb7434651 100644
--- a/chrome/browser/ui/views/app_list/app_list_controller_win.cc
+++ b/chrome/browser/ui/views/app_list/app_list_controller_win.cc
@@ -545,6 +545,8 @@ bool GetTaskbarRect(gfx::Rect* rect) {
 // |anchor| thus, using the location of the point in |point|, the distance
 // to move the view from |point| in |offset|, and the direction to move
 // represented in |direction|.
+// The function will also ensure the view is within |offset| of the screen
+// edges.
 // To position relative to a screen corner, the absolute values of |direction|.x
 // and |direction.y| should both be 1. To position relative to some point on the
 // taskbar, one of the absolute values of |direction.x| and |direction.y| should
@@ -552,9 +554,22 @@ bool GetTaskbarRect(gfx::Rect* rect) {
 void FloatFromPoint(const gfx::Point& point,
                     const gfx::Size& offset,
                     const gfx::Point& direction,
+                    const gfx::Rect& screen_rect,

[tapted, 2013/02/27 08:41:59]

bounds_rect, Then,

                     gfx::Point* anchor) {
   anchor->set_x(point.x() + direction.x() * offset.width());
   anchor->set_y(point.y() + direction.y() * offset.height());
+
+  if (anchor->x() - offset.width() < screen_rect.x())

[tapted, 2013/02/27 08:41:59]

I think these 11 lines can be just

anchor.ClampToMin(bounds_rect.bottom_left());
anchor.ClampToMax(bounds_rect.top_right());

+    anchor->set_x(screen_rect.x() + offset.width());
+
+  if (anchor->x() + offset.width() > screen_rect.right())
+    anchor->set_x(screen_rect.right() - offset.width());
+
+  if (anchor->y() - offset.height() < screen_rect.y())
+    anchor->set_y(screen_rect.y() + offset.height());
+
+  if (anchor->y() + offset.height() > screen_rect.bottom())
+    anchor->set_y(screen_rect.bottom() - offset.height());
 }
 
 void AppListController::SnapArrowLocationToTaskbarEdge(
@@ -569,6 +584,8 @@ void AppListController::SnapArrowLocationToTaskbarEdge(
   float_offset.set_height(float_offset.height() / 2);
   float_offset.Enlarge(kSnapOffset, kSnapOffset);

[tapted, 2013/02/27 08:42:30]

[ I think with this Enlarge, it also gets a margin around the edge of the
screen. i.e., it won't be flush against the edge of screen. Intentional? (if no,
this could be moved below the "Inset" in the next comment..) ]

 
+  const gfx::Rect& screen_rect = display.bounds();

[tapted, 2013/02/27 08:41:59]

With

gfx::Rect& bounds_rect = display.bounds();
bounds_rect.Inset(float_offset.width(), float_offset.height());

[tapted, 2013/02/27 08:41:59]

Does it need to take into account the taskbar, to ensure there is no overlap?
(My brain can't really come up with a scenario where that wouldn't be taken care
of by other the things below).

+
   // If we can't find the taskbar, snap to the bottom left.
   // If the display size is the same as the work area, and does not contain the
   // taskbar, either the taskbar is hidden or on another monitor, so just snap
@@ -579,12 +596,11 @@ void AppListController::SnapArrowLocationToTaskbarEdge(
     FloatFromPoint(display.work_area().bottom_left(),
                    float_offset,
                    gfx::Point(1, -1),
+                   screen_rect,
                    anchor);
     return;
   }
 
-  const gfx::Rect& screen_rect = display.bounds();
-
   // Snap to the taskbar edge. If the cursor is greater than kSnapDistance away,
   // also move to the left (for horizontal taskbars) or top (for vertical).
 
@@ -595,6 +611,7 @@ void AppListController::SnapArrowLocationToTaskbarEdge(
         FloatFromPoint(gfx::Point(screen_rect.x(), taskbar_rect.y()),
                        float_offset,
                        gfx::Point(1, -1),
+                       screen_rect,
                        anchor);
         return;
       }
@@ -602,6 +619,7 @@ void AppListController::SnapArrowLocationToTaskbarEdge(
       FloatFromPoint(gfx::Point(anchor->x(), taskbar_rect.y()),
                      float_offset,
                      gfx::Point(0, -1),
+                     screen_rect,
                      anchor);
       return;
     }
@@ -611,6 +629,7 @@ void AppListController::SnapArrowLocationToTaskbarEdge(
       FloatFromPoint(gfx::Point(screen_rect.x(), taskbar_rect.bottom()),
                      float_offset,
                      gfx::Point(1, 1),
+                     screen_rect,
                      anchor);
       return;
     }
@@ -618,6 +637,7 @@ void AppListController::SnapArrowLocationToTaskbarEdge(
     FloatFromPoint(gfx::Point(anchor->x(), taskbar_rect.bottom()),
                    float_offset,
                    gfx::Point(0, 1),
+                   screen_rect,
                    anchor);
     return;
   }
@@ -628,6 +648,7 @@ void AppListController::SnapArrowLocationToTaskbarEdge(
       FloatFromPoint(gfx::Point(taskbar_rect.right(), screen_rect.y()),
                      float_offset,
                      gfx::Point(1, 1),
+                     screen_rect,
                      anchor);
       return;
     }
@@ -635,6 +656,7 @@ void AppListController::SnapArrowLocationToTaskbarEdge(
     FloatFromPoint(gfx::Point(taskbar_rect.right(), anchor->y()),
                    float_offset,
                    gfx::Point(1, 0),
+                   screen_rect,
                    anchor);
     return;
   }
@@ -644,6 +666,7 @@ void AppListController::SnapArrowLocationToTaskbarEdge(
     FloatFromPoint(gfx::Point(taskbar_rect.x(), screen_rect.y()),
                    float_offset,
                    gfx::Point(-1, 1),
+                   screen_rect,
                    anchor);
     return;
   }
@@ -651,6 +674,7 @@ void AppListController::SnapArrowLocationToTaskbarEdge(
   FloatFromPoint(gfx::Point(taskbar_rect.x(), anchor->y()),
                  float_offset,
                  gfx::Point(-1, 0),
+                 screen_rect,
                  anchor);
 }