content/browser/renderer_host/input/tap_suppression_controller.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 "content/browser/renderer_host/input/tap_suppression_controller.h"
   6
   7 #include "base/debug/trace_event.h"
   8 #include "base/logging.h"
   9 #include "content/browser/renderer_host/input/tap_suppression_controller_client.h"
  10
  11 namespace content {
  12
  13 TapSuppressionController::Config::Config()
  14     : enabled(false),
  15       max_cancel_to_down_time(base::TimeDelta::FromMilliseconds(180)),
  16       max_tap_gap_time(base::TimeDelta::FromMilliseconds(500)) {
  17 }
  18
  19 TapSuppressionController::TapSuppressionController(
  20     TapSuppressionControllerClient* client,
  21     const Config& config)
  22     : client_(client),
  23       state_(config.enabled ? NOTHING : DISABLED),
  24       max_cancel_to_down_time_(config.max_cancel_to_down_time),
  25       max_tap_gap_time_(config.max_tap_gap_time) {
  26 }
  27
  28 TapSuppressionController::~TapSuppressionController() {}
  29
  30 void TapSuppressionController::GestureFlingCancel() {
  31   switch (state_) {
  32     case DISABLED:
  33       break;
  34     case NOTHING:
  35     case GFC_IN_PROGRESS:
  36     case LAST_CANCEL_STOPPED_FLING:
  37       state_ = GFC_IN_PROGRESS;
  38       break;
  39     case TAP_DOWN_STASHED:
  40       break;
  41   }
  42 }
  43
  44 void TapSuppressionController::GestureFlingCancelAck(bool processed) {
  45   base::TimeTicks event_time = Now();
  46   switch (state_) {
  47     case DISABLED:
  48     case NOTHING:
  49       break;
  50     case GFC_IN_PROGRESS:
  51       if (processed)
  52         fling_cancel_time_ = event_time;
  53       state_ = LAST_CANCEL_STOPPED_FLING;
  54       break;
  55     case TAP_DOWN_STASHED:
  56       if (!processed) {
  57         TRACE_EVENT0("browser",
  58                      "TapSuppressionController::GestureFlingCancelAck");
  59         StopTapDownTimer();
  60         client_->ForwardStashedTapDown();
  61         state_ = NOTHING;
  62       }  // Else waiting for the timer to release the stashed tap down.
  63       break;
  64     case LAST_CANCEL_STOPPED_FLING:
  65       break;
  66   }
  67 }
  68
  69 bool TapSuppressionController::ShouldDeferTapDown() {
  70   base::TimeTicks event_time = Now();
  71   switch (state_) {
  72     case DISABLED:
  73     case NOTHING:
  74       return false;
  75     case GFC_IN_PROGRESS:
  76       state_ = TAP_DOWN_STASHED;
  77       StartTapDownTimer(max_tap_gap_time_);
  78       return true;
  79     case TAP_DOWN_STASHED:
  80       NOTREACHED() << "TapDown on TAP_DOWN_STASHED state";
  81       state_ = NOTHING;
  82       return false;
  83     case LAST_CANCEL_STOPPED_FLING:
  84       if ((event_time - fling_cancel_time_) < max_cancel_to_down_time_) {
  85         state_ = TAP_DOWN_STASHED;
  86         StartTapDownTimer(max_tap_gap_time_);
  87         return true;
  88       } else {
  89         state_ = NOTHING;
  90         return false;
  91       }
  92   }
  93   NOTREACHED() << "Invalid state";
  94   return false;
  95 }
  96
  97 bool TapSuppressionController::ShouldSuppressTapEnd() {
  98   switch (state_) {
  99     case DISABLED:
 100     case NOTHING:
 101     case GFC_IN_PROGRESS:
 102       return false;
 103     case TAP_DOWN_STASHED:
 104       state_ = NOTHING;
 105       StopTapDownTimer();
 106       client_->DropStashedTapDown();
 107       return true;
 108     case LAST_CANCEL_STOPPED_FLING:
 109       NOTREACHED() << "Invalid tap end on LAST_CANCEL_STOPPED_FLING state";
 110   }
 111   return false;
 112 }
 113
 114 base::TimeTicks TapSuppressionController::Now() {
 115   return base::TimeTicks::Now();
 116 }
 117
 118 void TapSuppressionController::StartTapDownTimer(const base::TimeDelta& delay) {
 119   tap_down_timer_.Start(FROM_HERE, delay, this,
 120                         &TapSuppressionController::TapDownTimerExpired);
 121 }
 122
 123 void TapSuppressionController::StopTapDownTimer() {
 124   tap_down_timer_.Stop();
 125 }
 126
 127 void TapSuppressionController::TapDownTimerExpired() {
 128   switch (state_) {
 129     case DISABLED:
 130     case NOTHING:
 131       NOTREACHED() << "Timer fired on invalid state.";
 132       break;
 133     case GFC_IN_PROGRESS:
 134     case LAST_CANCEL_STOPPED_FLING:
 135       NOTREACHED() << "Timer fired on invalid state.";
 136       state_ = NOTHING;
 137       break;
 138     case TAP_DOWN_STASHED:
 139       TRACE_EVENT0("browser",
 140                    "TapSuppressionController::TapDownTimerExpired");
 141       client_->ForwardStashedTapDown();
 142       state_ = NOTHING;
 143       break;
 144   }
 145 }
 146
 147 }  // namespace content