1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/layers/apz/util/ActiveElementManager.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,153 @@
1.4 +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#include "ActiveElementManager.h"
1.10 +#include "mozilla/EventStates.h"
1.11 +#include "mozilla/Preferences.h"
1.12 +#include "mozilla/Services.h"
1.13 +#include "inIDOMUtils.h"
1.14 +#include "nsIDOMDocument.h"
1.15 +#include "nsIDOMElement.h"
1.16 +#include "nsIDOMEventTarget.h"
1.17 +#include "base/message_loop.h"
1.18 +#include "base/task.h"
1.19 +
1.20 +namespace mozilla {
1.21 +namespace layers {
1.22 +
1.23 +static int32_t sActivationDelayMs = 100;
1.24 +static bool sActivationDelayMsSet = false;
1.25 +
1.26 +ActiveElementManager::ActiveElementManager()
1.27 + : mDomUtils(services::GetInDOMUtils()),
1.28 + mCanBePan(false),
1.29 + mCanBePanSet(false),
1.30 + mSetActiveTask(nullptr)
1.31 +{
1.32 + if (!sActivationDelayMsSet) {
1.33 + Preferences::AddIntVarCache(&sActivationDelayMs,
1.34 + "ui.touch_activation.delay_ms",
1.35 + sActivationDelayMs);
1.36 + sActivationDelayMsSet = true;
1.37 + }
1.38 +}
1.39 +
1.40 +ActiveElementManager::~ActiveElementManager() {}
1.41 +
1.42 +void
1.43 +ActiveElementManager::SetTargetElement(nsIDOMEventTarget* aTarget)
1.44 +{
1.45 + if (mTarget) {
1.46 + // Multiple fingers on screen (since HandleTouchEnd clears mTarget).
1.47 + CancelTask();
1.48 + ResetActive();
1.49 + mTarget = nullptr;
1.50 + return;
1.51 + }
1.52 +
1.53 + mTarget = do_QueryInterface(aTarget);
1.54 + TriggerElementActivation();
1.55 +}
1.56 +
1.57 +void
1.58 +ActiveElementManager::HandleTouchStart(bool aCanBePan)
1.59 +{
1.60 + mCanBePan = aCanBePan;
1.61 + mCanBePanSet = true;
1.62 + TriggerElementActivation();
1.63 +}
1.64 +
1.65 +void
1.66 +ActiveElementManager::TriggerElementActivation()
1.67 +{
1.68 + // Both HandleTouchStart() and SetTargetElement() call this. They can be
1.69 + // called in either order. One will set mCanBePanSet, and the other, mTarget.
1.70 + // We want to actually trigger the activation once both are set.
1.71 + if (!(mTarget && mCanBePanSet)) {
1.72 + return;
1.73 + }
1.74 +
1.75 + // If the touch cannot be a pan, make mTarget :active right away.
1.76 + // Otherwise, wait a bit to see if the user will pan or not.
1.77 + if (!mCanBePan) {
1.78 + SetActive(mTarget);
1.79 + } else {
1.80 + mSetActiveTask = NewRunnableMethod(
1.81 + this, &ActiveElementManager::SetActiveTask, mTarget);
1.82 + MessageLoop::current()->PostDelayedTask(
1.83 + FROM_HERE, mSetActiveTask, sActivationDelayMs);
1.84 + }
1.85 +}
1.86 +
1.87 +void
1.88 +ActiveElementManager::HandlePanStart()
1.89 +{
1.90 + // The user started to pan, so we don't want mTarget to be :active.
1.91 + // Make it not :active, and clear any pending task to make it :active.
1.92 + CancelTask();
1.93 + ResetActive();
1.94 +}
1.95 +
1.96 +void
1.97 +ActiveElementManager::HandleTouchEnd(bool aWasClick)
1.98 +{
1.99 + // If the touch was a click, make mTarget :active right away.
1.100 + // nsEventStateManager will reset the active element when processing
1.101 + // the mouse-down event generated by the click.
1.102 + CancelTask();
1.103 + if (aWasClick) {
1.104 + SetActive(mTarget);
1.105 + }
1.106 +
1.107 + // Clear mTarget for next touch.
1.108 + mTarget = nullptr;
1.109 +}
1.110 +
1.111 +void
1.112 +ActiveElementManager::SetActive(nsIDOMElement* aTarget)
1.113 +{
1.114 + if (mDomUtils) {
1.115 + mDomUtils->SetContentState(aTarget, NS_EVENT_STATE_ACTIVE.GetInternalValue());;
1.116 + }
1.117 +}
1.118 +
1.119 +void
1.120 +ActiveElementManager::ResetActive()
1.121 +{
1.122 + // Clear the :active flag from mTarget by setting it on the document root.
1.123 + if (mTarget) {
1.124 + nsCOMPtr<nsIDOMDocument> doc;
1.125 + mTarget->GetOwnerDocument(getter_AddRefs(doc));
1.126 + if (doc) {
1.127 + nsCOMPtr<nsIDOMElement> root;
1.128 + doc->GetDocumentElement(getter_AddRefs(root));
1.129 + if (root) {
1.130 + SetActive(root);
1.131 + }
1.132 + }
1.133 + }
1.134 +}
1.135 +
1.136 +void
1.137 +ActiveElementManager::SetActiveTask(nsIDOMElement* aTarget)
1.138 +{
1.139 + // This gets called from mSetActiveTask's Run() method. The message loop
1.140 + // deletes the task right after running it, so we need to null out
1.141 + // mSetActiveTask to make sure we're not left with a dangling pointer.
1.142 + mSetActiveTask = nullptr;
1.143 + SetActive(aTarget);
1.144 +}
1.145 +
1.146 +void
1.147 +ActiveElementManager::CancelTask()
1.148 +{
1.149 + if (mSetActiveTask) {
1.150 + mSetActiveTask->Cancel();
1.151 + mSetActiveTask = nullptr;
1.152 + }
1.153 +}
1.154 +
1.155 +}
1.156 +}
