Home | History | Annotate | Download | only in menu 
      1 // Copyright (c) 2012 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 "ui/views/controls/menu/submenu_view.h"
      6 
      7 #include <algorithm>
      8 
      9 #include "base/compiler_specific.h"
     10 #include "ui/accessibility/ax_view_state.h"
     11 #include "ui/events/event.h"
     12 #include "ui/gfx/canvas.h"
     13 #include "ui/gfx/geometry/safe_integer_conversions.h"
     14 #include "ui/views/controls/menu/menu_config.h"
     15 #include "ui/views/controls/menu/menu_controller.h"
     16 #include "ui/views/controls/menu/menu_host.h"
     17 #include "ui/views/controls/menu/menu_item_view.h"
     18 #include "ui/views/controls/menu/menu_scroll_view_container.h"
     19 #include "ui/views/widget/root_view.h"
     20 #include "ui/views/widget/widget.h"
     21 
     22 namespace {
     23 
     24 // Height of the drop indicator. This should be an even number.
     25 const int kDropIndicatorHeight = 2;
     26 
     27 // Color of the drop indicator.
     28 const SkColor kDropIndicatorColor = SK_ColorBLACK;
     29 
     30 }  // namespace
     31 
     32 namespace views {
     33 
     34 // static
     35 const char SubmenuView::kViewClassName[] = "SubmenuView";
     36 
     37 SubmenuView::SubmenuView(MenuItemView* parent)
     38     : parent_menu_item_(parent),
     39       host_(NULL),
     40       drop_item_(NULL),
     41       drop_position_(MenuDelegate::DROP_NONE),
     42       scroll_view_container_(NULL),
     43       max_minor_text_width_(0),
     44       minimum_preferred_width_(0),
     45       resize_open_menu_(false),
     46       scroll_animator_(new ScrollAnimator(this)),
     47       roundoff_error_(0),
     48       prefix_selector_(this) {
     49   DCHECK(parent);
     50   // We'll delete ourselves, otherwise the ScrollView would delete us on close.
     51   set_owned_by_client();
     52 }
     53 
     54 SubmenuView::~SubmenuView() {
     55   // The menu may not have been closed yet (it will be hidden, but not
     56   // necessarily closed).
     57   Close();
     58 
     59   delete scroll_view_container_;
     60 }
     61 
     62 int SubmenuView::GetMenuItemCount() {
     63   int count = 0;
     64   for (int i = 0; i < child_count(); ++i) {
     65     if (child_at(i)->id() == MenuItemView::kMenuItemViewID)
     66       count++;
     67   }
     68   return count;
     69 }
     70 
     71 MenuItemView* SubmenuView::GetMenuItemAt(int index) {
     72   for (int i = 0, count = 0; i < child_count(); ++i) {
     73     if (child_at(i)->id() == MenuItemView::kMenuItemViewID &&
     74         count++ == index) {
     75       return static_cast<MenuItemView*>(child_at(i));
     76     }
     77   }
     78   NOTREACHED();
     79   return NULL;
     80 }
     81 
     82 void SubmenuView::ChildPreferredSizeChanged(View* child) {
     83   if (!resize_open_menu_)
     84     return;
     85 
     86   MenuItemView *item = GetMenuItem();
     87   MenuController* controller = item->GetMenuController();
     88 
     89   if (controller) {
     90     bool dir;
     91     gfx::Rect bounds = controller->CalculateMenuBounds(item, false, &dir);
     92     Reposition(bounds);
     93   }
     94 }
     95 
     96 void SubmenuView::Layout() {
     97   // We're in a ScrollView, and need to set our width/height ourselves.
     98   if (!parent())
     99     return;
    100 
    101   // Use our current y, unless it means part of the menu isn't visible anymore.
    102   int pref_height = GetPreferredSize().height();
    103   int new_y;
    104   if (pref_height > parent()->height())
    105     new_y = std::max(parent()->height() - pref_height, y());
    106   else
    107     new_y = 0;
    108   SetBounds(x(), new_y, parent()->width(), pref_height);
    109 
    110   gfx::Insets insets = GetInsets();
    111   int x = insets.left();
    112   int y = insets.top();
    113   int menu_item_width = width() - insets.width();
    114   for (int i = 0; i < child_count(); ++i) {
    115     View* child = child_at(i);
    116     if (child->visible()) {
    117       gfx::Size child_pref_size = child->GetPreferredSize();
    118       child->SetBounds(x, y, menu_item_width, child_pref_size.height());
    119       y += child_pref_size.height();
    120     }
    121   }
    122 }
    123 
    124 gfx::Size SubmenuView::GetPreferredSize() const {
    125   if (!has_children())
    126     return gfx::Size();
    127 
    128   max_minor_text_width_ = 0;
    129   // The maximum width of items which contain maybe a label and multiple views.
    130   int max_complex_width = 0;
    131   // The max. width of items which contain a label and maybe an accelerator.
    132   int max_simple_width = 0;
    133   int height = 0;
    134   for (int i = 0; i < child_count(); ++i) {
    135     const View* child = child_at(i);
    136     if (!child->visible())
    137       continue;
    138     if (child->id() == MenuItemView::kMenuItemViewID) {
    139       const MenuItemView* menu = static_cast<const MenuItemView*>(child);
    140       const MenuItemView::MenuItemDimensions& dimensions =
    141           menu->GetDimensions();
    142       max_simple_width = std::max(
    143           max_simple_width, dimensions.standard_width);
    144       max_minor_text_width_ =
    145           std::max(max_minor_text_width_, dimensions.minor_text_width);
    146       max_complex_width = std::max(max_complex_width,
    147           dimensions.standard_width + dimensions.children_width);
    148       height += dimensions.height;
    149     } else {
    150       gfx::Size child_pref_size =
    151           child->visible() ? child->GetPreferredSize() : gfx::Size();
    152       max_complex_width = std::max(max_complex_width, child_pref_size.width());
    153       height += child_pref_size.height();
    154     }
    155   }
    156   if (max_minor_text_width_ > 0) {
    157     max_minor_text_width_ +=
    158         GetMenuItem()->GetMenuConfig().label_to_minor_text_padding;
    159   }
    160   gfx::Insets insets = GetInsets();
    161   return gfx::Size(
    162       std::max(max_complex_width,
    163                std::max(max_simple_width + max_minor_text_width_ +
    164                         insets.width(),
    165                minimum_preferred_width_ - 2 * insets.width())),
    166       height + insets.height());
    167 }
    168 
    169 void SubmenuView::GetAccessibleState(ui::AXViewState* state) {
    170   // Inherit most of the state from the parent menu item, except the role.
    171   if (GetMenuItem())
    172     GetMenuItem()->GetAccessibleState(state);
    173   state->role = ui::AX_ROLE_MENU_LIST_POPUP;
    174 }
    175 
    176 ui::TextInputClient* SubmenuView::GetTextInputClient() {
    177   return &prefix_selector_;
    178 }
    179 
    180 void SubmenuView::PaintChildren(gfx::Canvas* canvas,
    181                                 const views::CullSet& cull_set) {
    182   View::PaintChildren(canvas, cull_set);
    183 
    184   if (drop_item_ && drop_position_ != MenuDelegate::DROP_ON)
    185     PaintDropIndicator(canvas, drop_item_, drop_position_);
    186 }
    187 
    188 bool SubmenuView::GetDropFormats(
    189       int* formats,
    190       std::set<OSExchangeData::CustomFormat>* custom_formats) {
    191   DCHECK(GetMenuItem()->GetMenuController());
    192   return GetMenuItem()->GetMenuController()->GetDropFormats(this, formats,
    193                                                             custom_formats);
    194 }
    195 
    196 bool SubmenuView::AreDropTypesRequired() {
    197   DCHECK(GetMenuItem()->GetMenuController());
    198   return GetMenuItem()->GetMenuController()->AreDropTypesRequired(this);
    199 }
    200 
    201 bool SubmenuView::CanDrop(const OSExchangeData& data) {
    202   DCHECK(GetMenuItem()->GetMenuController());
    203   return GetMenuItem()->GetMenuController()->CanDrop(this, data);
    204 }
    205 
    206 void SubmenuView::OnDragEntered(const ui::DropTargetEvent& event) {
    207   DCHECK(GetMenuItem()->GetMenuController());
    208   GetMenuItem()->GetMenuController()->OnDragEntered(this, event);
    209 }
    210 
    211 int SubmenuView::OnDragUpdated(const ui::DropTargetEvent& event) {
    212   DCHECK(GetMenuItem()->GetMenuController());
    213   return GetMenuItem()->GetMenuController()->OnDragUpdated(this, event);
    214 }
    215 
    216 void SubmenuView::OnDragExited() {
    217   DCHECK(GetMenuItem()->GetMenuController());
    218   GetMenuItem()->GetMenuController()->OnDragExited(this);
    219 }
    220 
    221 int SubmenuView::OnPerformDrop(const ui::DropTargetEvent& event) {
    222   DCHECK(GetMenuItem()->GetMenuController());
    223   return GetMenuItem()->GetMenuController()->OnPerformDrop(this, event);
    224 }
    225 
    226 bool SubmenuView::OnMouseWheel(const ui::MouseWheelEvent& e) {
    227   gfx::Rect vis_bounds = GetVisibleBounds();
    228   int menu_item_count = GetMenuItemCount();
    229   if (vis_bounds.height() == height() || !menu_item_count) {
    230     // All menu items are visible, nothing to scroll.
    231     return true;
    232   }
    233 
    234   // Find the index of the first menu item whose y-coordinate is >= visible
    235   // y-coordinate.
    236   int i = 0;
    237   while ((i < menu_item_count) && (GetMenuItemAt(i)->y() < vis_bounds.y()))
    238     ++i;
    239   if (i == menu_item_count)
    240     return true;
    241   int first_vis_index = std::max(0,
    242       (GetMenuItemAt(i)->y() == vis_bounds.y()) ? i : i - 1);
    243 
    244   // If the first item isn't entirely visible, make it visible, otherwise make
    245   // the next/previous one entirely visible. If enough wasn't scrolled to show
    246   // any new rows, then just scroll the amount so that smooth scrolling using
    247   // the trackpad is possible.
    248   int delta = abs(e.y_offset() / ui::MouseWheelEvent::kWheelDelta);
    249   if (delta == 0)
    250     return OnScroll(0, e.y_offset());
    251   for (bool scroll_up = (e.y_offset() > 0); delta != 0; --delta) {
    252     int scroll_target;
    253     if (scroll_up) {
    254       if (GetMenuItemAt(first_vis_index)->y() == vis_bounds.y()) {
    255         if (first_vis_index == 0)
    256           break;
    257         first_vis_index--;
    258       }
    259       scroll_target = GetMenuItemAt(first_vis_index)->y();
    260     } else {
    261       if (first_vis_index + 1 == menu_item_count)
    262         break;
    263       scroll_target = GetMenuItemAt(first_vis_index + 1)->y();
    264       if (GetMenuItemAt(first_vis_index)->y() == vis_bounds.y())
    265         first_vis_index++;
    266     }
    267     ScrollRectToVisible(gfx::Rect(gfx::Point(0, scroll_target),
    268                                   vis_bounds.size()));
    269     vis_bounds = GetVisibleBounds();
    270   }
    271 
    272   return true;
    273 }
    274 
    275 void SubmenuView::OnGestureEvent(ui::GestureEvent* event) {
    276   bool handled = true;
    277   switch (event->type()) {
    278     case ui::ET_GESTURE_SCROLL_BEGIN:
    279       scroll_animator_->Stop();
    280       break;
    281     case ui::ET_GESTURE_SCROLL_UPDATE:
    282       handled = OnScroll(0, event->details().scroll_y());
    283       break;
    284     case ui::ET_GESTURE_SCROLL_END:
    285       break;
    286     case ui::ET_SCROLL_FLING_START:
    287       if (event->details().velocity_y() != 0.0f)
    288         scroll_animator_->Start(0, event->details().velocity_y());
    289       break;
    290     case ui::ET_GESTURE_TAP_DOWN:
    291     case ui::ET_SCROLL_FLING_CANCEL:
    292       if (scroll_animator_->is_scrolling())
    293         scroll_animator_->Stop();
    294       else
    295         handled = false;
    296       break;
    297     default:
    298       handled = false;
    299       break;
    300   }
    301   if (handled)
    302     event->SetHandled();
    303 }
    304 
    305 int SubmenuView::GetRowCount() {
    306   return GetMenuItemCount();
    307 }
    308 
    309 int SubmenuView::GetSelectedRow() {
    310   int row = 0;
    311   for (int i = 0; i < child_count(); ++i) {
    312     if (child_at(i)->id() != MenuItemView::kMenuItemViewID)
    313       continue;
    314 
    315     if (static_cast<MenuItemView*>(child_at(i))->IsSelected())
    316       return row;
    317 
    318     row++;
    319   }
    320 
    321   return -1;
    322 }
    323 
    324 void SubmenuView::SetSelectedRow(int row) {
    325   GetMenuItem()->GetMenuController()->SetSelection(
    326       GetMenuItemAt(row),
    327       MenuController::SELECTION_DEFAULT);
    328 }
    329 
    330 base::string16 SubmenuView::GetTextForRow(int row) {
    331   return GetMenuItemAt(row)->title();
    332 }
    333 
    334 bool SubmenuView::IsShowing() {
    335   return host_ && host_->IsMenuHostVisible();
    336 }
    337 
    338 void SubmenuView::ShowAt(Widget* parent,
    339                          const gfx::Rect& bounds,
    340                          bool do_capture) {
    341   if (host_) {
    342     host_->ShowMenuHost(do_capture);
    343   } else {
    344     host_ = new MenuHost(this);
    345     // Force construction of the scroll view container.
    346     GetScrollViewContainer();
    347     // Force a layout since our preferred size may not have changed but our
    348     // content may have.
    349     InvalidateLayout();
    350     host_->InitMenuHost(parent, bounds, scroll_view_container_, do_capture);
    351   }
    352 
    353   GetScrollViewContainer()->NotifyAccessibilityEvent(
    354       ui::AX_EVENT_MENU_START,
    355       true);
    356   NotifyAccessibilityEvent(
    357       ui::AX_EVENT_MENU_POPUP_START,
    358       true);
    359 }
    360 
    361 void SubmenuView::Reposition(const gfx::Rect& bounds) {
    362   if (host_)
    363     host_->SetMenuHostBounds(bounds);
    364 }
    365 
    366 void SubmenuView::Close() {
    367   if (host_) {
    368     NotifyAccessibilityEvent(ui::AX_EVENT_MENU_POPUP_END, true);
    369     GetScrollViewContainer()->NotifyAccessibilityEvent(
    370         ui::AX_EVENT_MENU_END, true);
    371 
    372     host_->DestroyMenuHost();
    373     host_ = NULL;
    374   }
    375 }
    376 
    377 void SubmenuView::Hide() {
    378   if (host_)
    379     host_->HideMenuHost();
    380   if (scroll_animator_->is_scrolling())
    381     scroll_animator_->Stop();
    382 }
    383 
    384 void SubmenuView::ReleaseCapture() {
    385   if (host_)
    386     host_->ReleaseMenuHostCapture();
    387 }
    388 
    389 bool SubmenuView::SkipDefaultKeyEventProcessing(const ui::KeyEvent& e) {
    390   return views::FocusManager::IsTabTraversalKeyEvent(e);
    391 }
    392 
    393 MenuItemView* SubmenuView::GetMenuItem() const {
    394   return parent_menu_item_;
    395 }
    396 
    397 void SubmenuView::SetDropMenuItem(MenuItemView* item,
    398                                   MenuDelegate::DropPosition position) {
    399   if (drop_item_ == item && drop_position_ == position)
    400     return;
    401   SchedulePaintForDropIndicator(drop_item_, drop_position_);
    402   drop_item_ = item;
    403   drop_position_ = position;
    404   SchedulePaintForDropIndicator(drop_item_, drop_position_);
    405 }
    406 
    407 bool SubmenuView::GetShowSelection(MenuItemView* item) {
    408   if (drop_item_ == NULL)
    409     return true;
    410   // Something is being dropped on one of this menus items. Show the
    411   // selection if the drop is on the passed in item and the drop position is
    412   // ON.
    413   return (drop_item_ == item && drop_position_ == MenuDelegate::DROP_ON);
    414 }
    415 
    416 MenuScrollViewContainer* SubmenuView::GetScrollViewContainer() {
    417   if (!scroll_view_container_) {
    418     scroll_view_container_ = new MenuScrollViewContainer(this);
    419     // Otherwise MenuHost would delete us.
    420     scroll_view_container_->set_owned_by_client();
    421   }
    422   return scroll_view_container_;
    423 }
    424 
    425 void SubmenuView::MenuHostDestroyed() {
    426   host_ = NULL;
    427   GetMenuItem()->GetMenuController()->Cancel(MenuController::EXIT_DESTROYED);
    428 }
    429 
    430 const char* SubmenuView::GetClassName() const {
    431   return kViewClassName;
    432 }
    433 
    434 void SubmenuView::OnBoundsChanged(const gfx::Rect& previous_bounds) {
    435   SchedulePaint();
    436 }
    437 
    438 void SubmenuView::PaintDropIndicator(gfx::Canvas* canvas,
    439                                      MenuItemView* item,
    440                                      MenuDelegate::DropPosition position) {
    441   if (position == MenuDelegate::DROP_NONE)
    442     return;
    443 
    444   gfx::Rect bounds = CalculateDropIndicatorBounds(item, position);
    445   canvas->FillRect(bounds, kDropIndicatorColor);
    446 }
    447 
    448 void SubmenuView::SchedulePaintForDropIndicator(
    449     MenuItemView* item,
    450     MenuDelegate::DropPosition position) {
    451   if (item == NULL)
    452     return;
    453 
    454   if (position == MenuDelegate::DROP_ON) {
    455     item->SchedulePaint();
    456   } else if (position != MenuDelegate::DROP_NONE) {
    457     SchedulePaintInRect(CalculateDropIndicatorBounds(item, position));
    458   }
    459 }
    460 
    461 gfx::Rect SubmenuView::CalculateDropIndicatorBounds(
    462     MenuItemView* item,
    463     MenuDelegate::DropPosition position) {
    464   DCHECK(position != MenuDelegate::DROP_NONE);
    465   gfx::Rect item_bounds = item->bounds();
    466   switch (position) {
    467     case MenuDelegate::DROP_BEFORE:
    468       item_bounds.Offset(0, -kDropIndicatorHeight / 2);
    469       item_bounds.set_height(kDropIndicatorHeight);
    470       return item_bounds;
    471 
    472     case MenuDelegate::DROP_AFTER:
    473       item_bounds.Offset(0, item_bounds.height() - kDropIndicatorHeight / 2);
    474       item_bounds.set_height(kDropIndicatorHeight);
    475       return item_bounds;
    476 
    477     default:
    478       // Don't render anything for on.
    479       return gfx::Rect();
    480   }
    481 }
    482 
    483 bool SubmenuView::OnScroll(float dx, float dy) {
    484   const gfx::Rect& vis_bounds = GetVisibleBounds();
    485   const gfx::Rect& full_bounds = bounds();
    486   int x = vis_bounds.x();
    487   float y_f = vis_bounds.y() - dy - roundoff_error_;
    488   int y = gfx::ToRoundedInt(y_f);
    489   roundoff_error_ = y - y_f;
    490   // clamp y to [0, full_height - vis_height)
    491   y = std::min(y, full_bounds.height() - vis_bounds.height() - 1);
    492   y = std::max(y, 0);
    493   gfx::Rect new_vis_bounds(x, y, vis_bounds.width(), vis_bounds.height());
    494   if (new_vis_bounds != vis_bounds) {
    495     ScrollRectToVisible(new_vis_bounds);
    496     return true;
    497   }
    498   return false;
    499 }
    500 
    501 }  // namespace views
    502