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/wm/core/capture_controller.h"
6
7#include "ui/aura/window.h"
8#include "ui/aura/window_event_dispatcher.h"
9#include "ui/aura/window_tree_host.h"
10
11namespace wm {
12
13////////////////////////////////////////////////////////////////////////////////
14// CaptureController, public:
15
16void CaptureController::Attach(aura::Window* root) {
17  DCHECK_EQ(0u, root_windows_.count(root));
18  root_windows_.insert(root);
19  aura::client::SetCaptureClient(root, this);
20}
21
22void CaptureController::Detach(aura::Window* root) {
23  root_windows_.erase(root);
24  aura::client::SetCaptureClient(root, NULL);
25}
26
27////////////////////////////////////////////////////////////////////////////////
28// CaptureController, aura::client::CaptureClient implementation:
29
30void CaptureController::SetCapture(aura::Window* new_capture_window) {
31  if (capture_window_ == new_capture_window)
32    return;
33
34  // Make sure window has a root window.
35  DCHECK(!new_capture_window || new_capture_window->GetRootWindow());
36  DCHECK(!capture_window_ || capture_window_->GetRootWindow());
37
38  aura::Window* old_capture_window = capture_window_;
39  aura::Window* old_capture_root = old_capture_window ?
40      old_capture_window->GetRootWindow() : NULL;
41
42  // Copy the list in case it's modified out from under us.
43  RootWindows root_windows(root_windows_);
44
45  // If we're actually starting capture, then cancel any touches/gestures
46  // that aren't already locked to the new window, and transfer any on the
47  // old capture window to the new one.  When capture is released we have no
48  // distinction between the touches/gestures that were in the window all
49  // along (and so shouldn't be canceled) and those that got moved, so
50  // just leave them all where they are.
51  if (new_capture_window) {
52    ui::GestureRecognizer::Get()->TransferEventsTo(old_capture_window,
53        new_capture_window);
54  }
55
56  capture_window_ = new_capture_window;
57
58  for (RootWindows::const_iterator i = root_windows.begin();
59       i != root_windows.end(); ++i) {
60    aura::client::CaptureDelegate* delegate = (*i)->GetHost()->dispatcher();
61    delegate->UpdateCapture(old_capture_window, new_capture_window);
62  }
63
64  aura::Window* capture_root =
65      capture_window_ ? capture_window_->GetRootWindow() : NULL;
66  if (capture_root != old_capture_root) {
67    if (old_capture_root) {
68      aura::client::CaptureDelegate* delegate =
69          old_capture_root->GetHost()->dispatcher();
70      delegate->ReleaseNativeCapture();
71    }
72    if (capture_root) {
73      aura::client::CaptureDelegate* delegate =
74          capture_root->GetHost()->dispatcher();
75      delegate->SetNativeCapture();
76    }
77  }
78}
79
80void CaptureController::ReleaseCapture(aura::Window* window) {
81  if (capture_window_ != window)
82    return;
83  SetCapture(NULL);
84}
85
86aura::Window* CaptureController::GetCaptureWindow() {
87  return capture_window_;
88}
89
90aura::Window* CaptureController::GetGlobalCaptureWindow() {
91  return capture_window_;
92}
93
94////////////////////////////////////////////////////////////////////////////////
95// CaptureController, private:
96
97CaptureController::CaptureController()
98    : capture_window_(NULL) {
99}
100
101CaptureController::~CaptureController() {
102}
103
104////////////////////////////////////////////////////////////////////////////////
105// ScopedCaptureClient:
106
107// static
108CaptureController* ScopedCaptureClient::capture_controller_ = NULL;
109
110ScopedCaptureClient::ScopedCaptureClient(aura::Window* root)
111    : root_window_(root) {
112  root->AddObserver(this);
113  if (!capture_controller_)
114    capture_controller_ = new CaptureController;
115  capture_controller_->Attach(root);
116}
117
118ScopedCaptureClient::~ScopedCaptureClient() {
119  Shutdown();
120}
121
122// static
123bool ScopedCaptureClient::IsActive() {
124  return capture_controller_ && capture_controller_->is_active();
125}
126
127void ScopedCaptureClient::OnWindowDestroyed(aura::Window* window) {
128  DCHECK_EQ(window, root_window_);
129  Shutdown();
130}
131
132void ScopedCaptureClient::Shutdown() {
133  if (!root_window_)
134    return;
135
136  root_window_->RemoveObserver(this);
137  capture_controller_->Detach(root_window_);
138  if (!capture_controller_->is_active()) {
139    delete capture_controller_;
140    capture_controller_ = NULL;
141  }
142  root_window_ = NULL;
143}
144
145}  // namespace wm
146