src/chrome/browser/ui/views/app_list/win/app_list_win.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/browser/ui/views/app_list/win/app_list_win.h"
   6
   7 #include "chrome/browser/ui/app_list/app_list_positioner.h"
   8 #include "ui/app_list/app_list_switches.h"
   9 #include "ui/app_list/views/app_list_view.h"
  10 #include "ui/gfx/screen.h"
  11 #include "ui/views/widget/widget.h"
  12
  13 namespace {
  14
  15 static const wchar_t kTrayClassName[] = L"Shell_TrayWnd";
  16
  17 // If the mouse cursor is less than this distance, in pixels, away from the
  18 // taskbar, it is considered to be in the taskbar for the purpose of anchoring.
  19 static const int kSnapDistance = 50;
  20
  21 // The minimum distance, in pixels, to position the app list from the taskbar or
  22 // edge of screen.
  23 static const int kMinDistanceFromEdge = 3;
  24
  25 // Utility methods for showing the app list.
  26 // Attempts to find the bounds of the Windows taskbar. Returns true on success.
  27 // |rect| is in screen coordinates. If the taskbar is in autohide mode and is
  28 // not visible, |rect| will be outside the current monitor's bounds, except for
  29 // one pixel of overlap where the edge of the taskbar is shown.
  30 bool GetTaskbarRect(gfx::Rect* rect) {
  31   HWND taskbar_hwnd = FindWindow(kTrayClassName, NULL);
  32   if (!taskbar_hwnd)
  33     return false;
  34
  35   RECT win_rect;
  36   if (!GetWindowRect(taskbar_hwnd, &win_rect))
  37     return false;
  38
  39   *rect = gfx::Rect(win_rect);
  40   return true;
  41 }
  42
  43 }  // namespace
  44
  45 // static
  46 gfx::Point AppListWin::FindAnchorPoint(const gfx::Size& view_size,
  47                                        const gfx::Display& display,
  48                                        const gfx::Point& cursor,
  49                                        const gfx::Rect& taskbar_rect,
  50                                        bool center_window) {
  51   AppListPositioner positioner(display, view_size, kMinDistanceFromEdge);
  52
  53   // Subtract the taskbar area since the display's default work_area will not
  54   // subtract it if the taskbar is set to auto-hide, and the app list should
  55   // never overlap the taskbar.
  56   positioner.WorkAreaSubtract(taskbar_rect);
  57
  58   // Special case for app list in the center of the screen.
  59   if (center_window)
  60     return positioner.GetAnchorPointForScreenCenter();
  61
  62   // Find which edge of the screen the taskbar is attached to.
  63   AppListPositioner::ScreenEdge edge = positioner.GetShelfEdge(taskbar_rect);
  64
  65   // Snap to the taskbar edge. If the cursor is greater than kSnapDistance away,
  66   // anchor to the corner. Otherwise, anchor to the cursor position.
  67   gfx::Point anchor;
  68   if (edge == AppListPositioner::SCREEN_EDGE_UNKNOWN) {
  69     // If we can't find the taskbar, snap to the bottom left.
  70     return positioner.GetAnchorPointForScreenCorner(
  71         AppListPositioner::SCREEN_CORNER_BOTTOM_LEFT);
  72   }
  73
  74   if (positioner.GetCursorDistanceFromShelf(edge, cursor) > kSnapDistance)
  75     return positioner.GetAnchorPointForShelfCorner(edge);
  76
  77   return positioner.GetAnchorPointForShelfCursor(edge, cursor);
  78 }
  79
  80 // static
  81 void AppListWin::MoveNearCursor(app_list::AppListView* view) {
  82   gfx::Point cursor = gfx::Screen::GetNativeScreen()->GetCursorScreenPoint();
  83   gfx::Screen* screen =
  84       gfx::Screen::GetScreenFor(view->GetWidget()->GetNativeView());
  85   gfx::Display display = screen->GetDisplayNearestPoint(cursor);
  86
  87   view->SetBubbleArrow(views::BubbleBorder::FLOAT);
  88   gfx::Rect taskbar_rect;
  89   GetTaskbarRect(&taskbar_rect);
  90   view->SetAnchorPoint(FindAnchorPoint(view->GetPreferredSize(),
  91                                        display,
  92                                        cursor,
  93                                        taskbar_rect,
  94                                        view->ShouldCenterWindow()));
  95 }