chrome/browser/ui/views/dropdown_bar_host.cc

   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 "chrome/browser/ui/views/dropdown_bar_host.h"
   6
   7 #include <algorithm>
   8
   9 #include "chrome/browser/ui/view_ids.h"
  10 #include "chrome/browser/ui/views/dropdown_bar_host_delegate.h"
  11 #include "chrome/browser/ui/views/dropdown_bar_view.h"
  12 #include "chrome/browser/ui/views/frame/browser_view.h"
  13 #include "ui/events/keycodes/keyboard_codes.h"
  14 #include "ui/gfx/animation/slide_animation.h"
  15 #include "ui/gfx/path.h"
  16 #include "ui/gfx/scoped_sk_region.h"
  17 #include "ui/gfx/scrollbar_size.h"
  18 #include "ui/views/focus/external_focus_tracker.h"
  19 #include "ui/views/focus/view_storage.h"
  20 #include "ui/views/widget/widget.h"
  21
  22 using gfx::Path;
  23
  24 // static
  25 bool DropdownBarHost::disable_animations_during_testing_ = false;
  26
  27 ////////////////////////////////////////////////////////////////////////////////
  28 // DropdownBarHost, public:
  29
  30 DropdownBarHost::DropdownBarHost(BrowserView* browser_view)
  31     : browser_view_(browser_view),
  32       view_(NULL),
  33       delegate_(NULL),
  34       animation_offset_(0),
  35       focus_manager_(NULL),
  36       esc_accel_target_registered_(false),
  37       is_visible_(false) {
  38 }
  39
  40 void DropdownBarHost::Init(views::View* host_view,
  41                            views::View* view,
  42                            DropdownBarHostDelegate* delegate) {
  43   DCHECK(view);
  44   DCHECK(delegate);
  45
  46   view_ = view;
  47   delegate_ = delegate;
  48
  49   // Initialize the host.
  50   host_.reset(new views::Widget);
  51   views::Widget::InitParams params(views::Widget::InitParams::TYPE_CONTROL);
  52   params.ownership = views::Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
  53   params.parent = browser_view_->GetWidget()->GetNativeView();
  54   params.opacity = views::Widget::InitParams::TRANSLUCENT_WINDOW;
  55   host_->Init(params);
  56   host_->SetContentsView(view_);
  57
  58   SetHostViewNative(host_view);
  59
  60   // Start listening to focus changes, so we can register and unregister our
  61   // own handler for Escape.
  62   focus_manager_ = host_->GetFocusManager();
  63   if (focus_manager_) {
  64     focus_manager_->AddFocusChangeListener(this);
  65   } else {
  66     // In some cases (see bug http://crbug.com/17056) it seems we may not have
  67     // a focus manager.  Please reopen the bug if you hit this.
  68     NOTREACHED();
  69   }
  70
  71   // Start the process of animating the opening of the widget.
  72   animation_.reset(new gfx::SlideAnimation(this));
  73 }
  74
  75 DropdownBarHost::~DropdownBarHost() {
  76   focus_manager_->RemoveFocusChangeListener(this);
  77   focus_tracker_.reset(NULL);
  78 }
  79
  80 void DropdownBarHost::Show(bool animate) {
  81   // Stores the currently focused view, and tracks focus changes so that we can
  82   // restore focus when the dropdown widget is closed.
  83   focus_tracker_.reset(new views::ExternalFocusTracker(view_, focus_manager_));
  84
  85   bool was_visible = is_visible_;
  86   is_visible_ = true;
  87   if (!animate || disable_animations_during_testing_) {
  88     animation_->Reset(1);
  89     AnimationProgressed(animation_.get());
  90   } else if (!was_visible) {
  91     // Don't re-start the animation.
  92     animation_->Reset();
  93     animation_->Show();
  94   }
  95
  96   if (!was_visible)
  97     OnVisibilityChanged();
  98 }
  99
 100 void DropdownBarHost::SetFocusAndSelection() {
 101   delegate_->SetFocusAndSelection(true);
 102 }
 103
 104 bool DropdownBarHost::IsAnimating() const {
 105   return animation_->is_animating();
 106 }
 107
 108 void DropdownBarHost::Hide(bool animate) {
 109   if (!IsVisible())
 110     return;
 111   if (animate && !disable_animations_during_testing_ &&
 112       !animation_->IsClosing()) {
 113     animation_->Hide();
 114   } else {
 115     if (animation_->IsClosing()) {
 116       // If we're in the middle of a close animation, skip immediately to the
 117       // end of the animation.
 118       StopAnimation();
 119     } else {
 120       // Otherwise we need to set both the animation state to ended and the
 121       // DropdownBarHost state to ended/hidden, otherwise the next time we try
 122       // to show the bar, it might refuse to do so. Note that we call
 123       // AnimationEnded ourselves as Reset does not call it if we are not
 124       // animating here.
 125       animation_->Reset();
 126       AnimationEnded(animation_.get());
 127     }
 128   }
 129 }
 130
 131 void DropdownBarHost::StopAnimation() {
 132   animation_->End();
 133 }
 134
 135 bool DropdownBarHost::IsVisible() const {
 136   return is_visible_;
 137 }
 138
 139 ////////////////////////////////////////////////////////////////////////////////
 140 // DropdownBarHost, views::FocusChangeListener implementation:
 141 void DropdownBarHost::OnWillChangeFocus(views::View* focused_before,
 142                                         views::View* focused_now) {
 143   // First we need to determine if one or both of the views passed in are child
 144   // views of our view.
 145   bool our_view_before = focused_before && view_->Contains(focused_before);
 146   bool our_view_now = focused_now && view_->Contains(focused_now);
 147
 148   // When both our_view_before and our_view_now are false, it means focus is
 149   // changing hands elsewhere in the application (and we shouldn't do anything).
 150   // Similarly, when both are true, focus is changing hands within the dropdown
 151   // widget (and again, we should not do anything). We therefore only need to
 152   // look at when we gain initial focus and when we loose it.
 153   if (!our_view_before && our_view_now) {
 154     // We are gaining focus from outside the dropdown widget so we must register
 155     // a handler for Escape.
 156     RegisterAccelerators();
 157   } else if (our_view_before && !our_view_now) {
 158     // We are losing focus to something outside our widget so we restore the
 159     // original handler for Escape.
 160     UnregisterAccelerators();
 161   }
 162 }
 163
 164 void DropdownBarHost::OnDidChangeFocus(views::View* focused_before,
 165                                        views::View* focused_now) {
 166 }
 167
 168 ////////////////////////////////////////////////////////////////////////////////
 169 // DropdownBarHost, gfx::AnimationDelegate implementation:
 170
 171 void DropdownBarHost::AnimationProgressed(const gfx::Animation* animation) {
 172   // First, we calculate how many pixels to slide the widget.
 173   gfx::Size pref_size = view_->GetPreferredSize();
 174   animation_offset_ = static_cast<int>((1.0 - animation_->GetCurrentValue()) *
 175                                        pref_size.height());
 176
 177   // This call makes sure it appears in the right location, the size and shape
 178   // is correct and that it slides in the right direction.
 179   gfx::Rect dlg_rect = GetDialogPosition(gfx::Rect());
 180   SetDialogPosition(dlg_rect, false);
 181
 182   // Let the view know if we are animating, and at which offset to draw the
 183   // edges.
 184   delegate_->SetAnimationOffset(animation_offset_);
 185   view_->SchedulePaint();
 186 }
 187
 188 void DropdownBarHost::AnimationEnded(const gfx::Animation* animation) {
 189   // Place the dropdown widget in its fully opened state.
 190   animation_offset_ = 0;
 191
 192   if (!animation_->IsShowing()) {
 193     // Animation has finished closing.
 194     host_->Hide();
 195     is_visible_ = false;
 196     OnVisibilityChanged();
 197   } else {
 198     // Animation has finished opening.
 199   }
 200 }
 201
 202 ////////////////////////////////////////////////////////////////////////////////
 203 // DropdownBarHost protected:
 204
 205 void DropdownBarHost::ResetFocusTracker() {
 206   focus_tracker_.reset(NULL);
 207 }
 208
 209 void DropdownBarHost::OnVisibilityChanged() {
 210 }
 211
 212 void DropdownBarHost::GetWidgetBounds(gfx::Rect* bounds) {
 213   DCHECK(bounds);
 214   *bounds = browser_view_->bounds();
 215 }
 216
 217 void DropdownBarHost::UpdateWindowEdges(const gfx::Rect& new_pos) {
 218   // |w| is used to make it easier to create the part of the polygon that curves
 219   // the right side of the Find window. It essentially keeps track of the
 220   // x-pixel position of the right-most background image inside the view.
 221   // TODO(finnur): Let the view tell us how to draw the curves or convert
 222   // this to a CustomFrameWindow.
 223   int w = new_pos.width() - 6;  // -6 positions us at the left edge of the
 224                                 // rightmost background image of the view.
 225   int h = new_pos.height();
 226
 227   // This polygon array represents the outline of the background image for the
 228   // window. Basically, it encompasses only the visible pixels of the
 229   // concatenated find_dlg_LMR_bg images (where LMR = [left | middle | right]).
 230   const Path::Point polygon[] = {
 231       {2, 0}, {3, 1}, {3, h - 2}, {4, h - 1},
 232         {4, h}, {w+0, h},
 233       {w+2, h - 1}, {w+3, h - 2}, {w+3, 1}, {w+4, 0}
 234   };
 235
 236   // Find the largest x and y value in the polygon.
 237   int max_x = 0, max_y = 0;
 238   for (size_t i = 0; i < arraysize(polygon); i++) {
 239     max_x = std::max(max_x, static_cast<int>(polygon[i].x));
 240     max_y = std::max(max_y, static_cast<int>(polygon[i].y));
 241   }
 242
 243   // We then create the polygon and use SetWindowRgn to force the window to draw
 244   // only within that area. This region may get reduced in size below.
 245   Path path(polygon, arraysize(polygon));
 246   gfx::ScopedSkRegion region(path.CreateNativeRegion());
 247   // Are we animating?
 248   if (animation_offset() > 0) {
 249     // The animation happens in two steps: First, we clip the window and then in
 250     // GetWidgetPosition we offset the window position so that it still looks
 251     // attached to the toolbar as it grows. We clip the window by creating a
 252     // rectangle region (that gradually increases as the animation progresses)
 253     // and find the intersection between the two regions using CombineRgn.
 254
 255     // |y| shrinks as the animation progresses from the height of the view down
 256     // to 0 (and reverses when closing).
 257     int y = animation_offset();
 258     // |y| shrinking means the animation (visible) region gets larger. In other
 259     // words: the rectangle grows upward (when the widget is opening).
 260     Path animation_path;
 261     SkRect animation_rect = { SkIntToScalar(0), SkIntToScalar(y),
 262                               SkIntToScalar(max_x), SkIntToScalar(max_y) };
 263     animation_path.addRect(animation_rect);
 264     gfx::ScopedSkRegion animation_region(
 265         animation_path.CreateNativeRegion());
 266     region.Set(Path::IntersectRegions(animation_region.Get(), region.Get()));
 267
 268     // Next, we need to increase the region a little bit to account for the
 269     // curved edges that the view will draw to make it look like grows out of
 270     // the toolbar.
 271     Path::Point left_curve[] = {
 272       {2, y+0}, {3, y+1}, {3, y+0}, {2, y+0}
 273     };
 274     Path::Point right_curve[] = {
 275       {w+3, y+1}, {w+4, y+0}, {w+3, y+0}, {w+3, y+1}
 276     };
 277
 278     // Combine the region for the curve on the left with our main region.
 279     Path left_path(left_curve, arraysize(left_curve));
 280     gfx::ScopedSkRegion r(left_path.CreateNativeRegion());
 281     region.Set(Path::CombineRegions(r.Get(), region.Get()));
 282
 283     // Combine the region for the curve on the right with our main region.
 284     Path right_path(right_curve, arraysize(right_curve));
 285     region.Set(Path::CombineRegions(r.Get(), region.Get()));
 286   }
 287
 288   // Now see if we need to truncate the region because parts of it obscures
 289   // the main window border.
 290   gfx::Rect widget_bounds;
 291   GetWidgetBounds(&widget_bounds);
 292
 293   // Calculate how much our current position overlaps our boundaries. If we
 294   // overlap, it means we have too little space to draw the whole widget and
 295   // we allow overwriting the scrollbar before we start truncating our widget.
 296   //
 297   // TODO(brettw) this constant is evil. This is the amount of room we've added
 298   // to the window size, when we set the region, it can change the size.
 299   static const int kAddedWidth = 7;
 300   int difference = new_pos.right() - kAddedWidth - widget_bounds.right() -
 301       gfx::scrollbar_size() + 1;
 302   if (difference > 0) {
 303     Path::Point exclude[4];
 304     exclude[0].x = max_x - difference;  // Top left corner.
 305     exclude[0].y = 0;
 306
 307     exclude[1].x = max_x;               // Top right corner.
 308     exclude[1].y = 0;
 309
 310     exclude[2].x = max_x;               // Bottom right corner.
 311     exclude[2].y = max_y;
 312
 313     exclude[3].x = max_x - difference;  // Bottom left corner.
 314     exclude[3].y = max_y;
 315
 316     // Subtract this region from the original region.
 317     gfx::Path exclude_path(exclude, arraysize(exclude));
 318     gfx::ScopedSkRegion exclude_region(exclude_path.CreateNativeRegion());
 319     region.Set(Path::SubtractRegion(region.Get(), exclude_region.Get()));
 320   }
 321
 322   // Window takes ownership of the region.
 323   host()->SetShape(region.release());
 324 }
 325
 326 void DropdownBarHost::RegisterAccelerators() {
 327   DCHECK(!esc_accel_target_registered_);
 328   ui::Accelerator escape(ui::VKEY_ESCAPE, ui::EF_NONE);
 329   focus_manager_->RegisterAccelerator(
 330       escape, ui::AcceleratorManager::kNormalPriority, this);
 331   esc_accel_target_registered_ = true;
 332 }
 333
 334 void DropdownBarHost::UnregisterAccelerators() {
 335   DCHECK(esc_accel_target_registered_);
 336   ui::Accelerator escape(ui::VKEY_ESCAPE, ui::EF_NONE);
 337   focus_manager_->UnregisterAccelerator(escape, this);
 338   esc_accel_target_registered_ = false;
 339 }