Bug 657634 Don't use high resolution scrolling when scrolling speed is customized by prefs r=smaug

content/events/src/nsEventStateManager.cpp

@@ -1225,20 +1225,8 @@ nsEventStateManager::PreHandleEvent(nsPresContext* aPresContext,
 
       nsMouseScrollEvent* msEvent = static_cast<nsMouseScrollEvent*>(aEvent);
 
-      NS_NAMED_LITERAL_CSTRING(actionslot,      ".action");
+      PRBool useSysNumLines = UseSystemScrollSettingFor(msEvent);
-      NS_NAMED_LITERAL_CSTRING(numlinesslot,    ".numlines");
+      PRInt32 action = GetWheelActionFor(msEvent);
-      NS_NAMED_LITERAL_CSTRING(sysnumlinesslot, ".sysnumlines");
-
-      nsCAutoString baseKey;
-      GetBasePrefKeyForMouseWheel(msEvent, baseKey);
-
-      nsCAutoString sysNumLinesKey(baseKey);
-      sysNumLinesKey.Append(sysnumlinesslot);
-      PRBool useSysNumLines = nsContentUtils::GetBoolPref(sysNumLinesKey.get());
-
-      nsCAutoString actionKey(baseKey);
-      actionKey.Append(actionslot);
-      PRInt32 action = nsContentUtils::GetIntPref(actionKey.get());
 
       if (!useSysNumLines) {
         // If the scroll event's delta isn't to our liking, we can
@@ -1254,9 +1242,7 @@ nsEventStateManager::PreHandleEvent(nsPresContext* aPresContext,
         // second item, if the parameter is negative we swap
         // directions.
 
-        nsCAutoString numLinesKey(baseKey);
+        PRInt32 numLines = GetScrollLinesFor(msEvent);
-        numLinesKey.Append(numlinesslot);
-        PRInt32 numLines = nsContentUtils::GetIntPref(numLinesKey.get());
 
         PRBool swapDirs = (numLines < 0);
         PRInt32 userSize = swapDirs ? -numLines : numLines;
@@ -2573,6 +2559,66 @@ nsEventStateManager::SendPixelScrollEvent(nsIFrame* aTargetFrame,
   nsEventDispatcher::Dispatch(targetContent, aPresContext, &event, nsnull, aStatus);
 }
 
+PRInt32
+nsEventStateManager::ComputeWheelActionFor(nsMouseScrollEvent* aMouseEvent,
+                                           PRBool aUseSystemSettings)
+{
+  PRInt32 action = GetWheelActionFor(aMouseEvent);
+  if (aUseSystemSettings &&
+      (aMouseEvent->scrollFlags & nsMouseScrollEvent::kIsFullPage)) {
+    action = MOUSE_SCROLL_PAGE;
+  }
+
+  if (aMouseEvent->message == NS_MOUSE_PIXEL_SCROLL) {
+    if (action == MOUSE_SCROLL_N_LINES || action == MOUSE_SCROLL_PAGE ||
+        (aMouseEvent->scrollFlags & nsMouseScrollEvent::kIsMomentum)) {
+      action = MOUSE_SCROLL_PIXELS;
+    } else {
+      // Do not scroll pixels when zooming
+      action = -1;
+    }
+  } else if (aMouseEvent->scrollFlags & nsMouseScrollEvent::kHasPixels) {
+    if (aUseSystemSettings ||
+        action == MOUSE_SCROLL_N_LINES || action == MOUSE_SCROLL_PAGE ||
+        (aMouseEvent->scrollFlags & nsMouseScrollEvent::kIsMomentum)) {
+      // Don't scroll lines when a pixel scroll event will follow.
+      // Also, don't do history scrolling or zooming for momentum scrolls.
+      action = -1;
+    }
+  }
+
+  return action;
+}
+
+PRInt32
+nsEventStateManager::GetWheelActionFor(nsMouseScrollEvent* aMouseEvent)
+{
+  nsCAutoString prefName;
+  GetBasePrefKeyForMouseWheel(aMouseEvent, prefName);
+  prefName.Append(".action");
+  return nsContentUtils::GetIntPref(prefName.get());
+}
+
+PRInt32
+nsEventStateManager::GetScrollLinesFor(nsMouseScrollEvent* aMouseEvent)
+{
+  NS_ASSERTION(!UseSystemScrollSettingFor(aMouseEvent),
+    "GetScrollLinesFor() called when should use system settings");
+  nsCAutoString prefName;
+  GetBasePrefKeyForMouseWheel(aMouseEvent, prefName);
+  prefName.Append(".numlines");
+  return nsContentUtils::GetIntPref(prefName.get());
+}
+
+PRBool
+nsEventStateManager::UseSystemScrollSettingFor(nsMouseScrollEvent* aMouseEvent)
+{
+  nsCAutoString prefName;
+  GetBasePrefKeyForMouseWheel(aMouseEvent, prefName);
+  prefName.Append(".sysnumlines");
+  return nsContentUtils::GetBoolPref(prefName.get());
+}
+
 nsresult
 nsEventStateManager::DoScrollText(nsIFrame* aTargetFrame,
                                   nsMouseScrollEvent* aMouseEvent,
@@ -3062,45 +3108,8 @@ nsEventStateManager::PostHandleEvent(nsPresContext* aPresContext,
       }
 
       if (*aStatus != nsEventStatus_eConsumeNoDefault) {
-        // Build the preference keys, based on the event properties.
+        PRBool useSysNumLines = UseSystemScrollSettingFor(msEvent);
-        NS_NAMED_LITERAL_CSTRING(actionslot,      ".action");
+        PRInt32 action = ComputeWheelActionFor(msEvent, useSysNumLines);
-        NS_NAMED_LITERAL_CSTRING(sysnumlinesslot, ".sysnumlines");
-
-        nsCAutoString baseKey;
-        GetBasePrefKeyForMouseWheel(msEvent, baseKey);
-
-        // Extract the preferences
-        nsCAutoString actionKey(baseKey);
-        actionKey.Append(actionslot);
-
-        nsCAutoString sysNumLinesKey(baseKey);
-        sysNumLinesKey.Append(sysnumlinesslot);
-
-        PRInt32 action = nsContentUtils::GetIntPref(actionKey.get());
-        PRBool useSysNumLines =
-          nsContentUtils::GetBoolPref(sysNumLinesKey.get());
-
-        if (useSysNumLines) {
-          if (msEvent->scrollFlags & nsMouseScrollEvent::kIsFullPage)
-            action = MOUSE_SCROLL_PAGE;
-        }
-
-        if (aEvent->message == NS_MOUSE_PIXEL_SCROLL) {
-          if (action == MOUSE_SCROLL_N_LINES || action == MOUSE_SCROLL_PAGE ||
-              (msEvent->scrollFlags & nsMouseScrollEvent::kIsMomentum)) {
-             action = MOUSE_SCROLL_PIXELS;
-          } else {
-            // Do not scroll pixels when zooming
-            action = -1;
-          }
-        } else if (msEvent->scrollFlags & nsMouseScrollEvent::kHasPixels) {
-          if (useSysNumLines || action == MOUSE_SCROLL_N_LINES ||
-              (msEvent->scrollFlags & nsMouseScrollEvent::kIsMomentum)) {
-            // Don't scroll lines when a pixel scroll event will follow.
-            // Also, don't do history scrolling or zooming for momentum scrolls.
-            action = -1;
-          }
-        }
 
         switch (action) {
         case MOUSE_SCROLL_N_LINES:
@@ -4686,13 +4695,35 @@ nsEventStateManager::DoQueryScrollTargetInfo(nsQueryContentEvent* aEvent,
                                              nsIFrame* aTargetFrame)
 {
   nsMouseScrollEvent* msEvent = aEvent->mInput.mMouseScrollEvent;
-  nsIScrollableFrame::ScrollUnit unit;
+
-  if (msEvent->scrollFlags & nsMouseScrollEvent::kIsFullPage) {
+  // Don't use high resolution scrolling when user customize the scrolling
-    unit = nsIScrollableFrame::PAGES;
+  // speed.
-  } else {
+  if (!UseSystemScrollSettingFor(msEvent)) {
-    unit = nsIScrollableFrame::LINES;
+    return;
   }
-  DoScrollText(aTargetFrame, msEvent, unit, PR_FALSE, aEvent);
+
+  nsIScrollableFrame::ScrollUnit unit;
+  PRBool allowOverrideSystemSettings;
+  switch (ComputeWheelActionFor(msEvent, PR_TRUE)) {
+    case MOUSE_SCROLL_N_LINES:
+      unit = nsIScrollableFrame::LINES;
+      allowOverrideSystemSettings = PR_TRUE;
+      break;
+    case MOUSE_SCROLL_PAGE:
+      unit = nsIScrollableFrame::PAGES;
+      allowOverrideSystemSettings = PR_FALSE;
+      break;
+    case MOUSE_SCROLL_PIXELS:
+      unit = nsIScrollableFrame::DEVICE_PIXELS;
+      allowOverrideSystemSettings = PR_FALSE;
+    default:
+      // Don't use high resolution scrolling when the action doesn't scroll
+      // contents.
+      return;
+  }
+
+  DoScrollText(aTargetFrame, msEvent, unit,
+               allowOverrideSystemSettings, aEvent);
 }
 
 void

content/events/src/nsEventStateManager.h

@@ -342,6 +342,33 @@ protected:
   nsresult GetMarkupDocumentViewer(nsIMarkupDocumentViewer** aMv);
   nsresult ChangeTextSize(PRInt32 change);
   nsresult ChangeFullZoom(PRInt32 change);
+  /**
+   * Computes the action for the aMouseEvent with prefs.  The result is
+   * MOUSE_SCROLL_N_LINES, MOUSE_SCROLL_PAGE, MOUSE_SCROLL_HISTORY,
+   * MOUSE_SCROLL_ZOOM, MOUSE_SCROLL_PIXELS or -1.
+   * When the result is -1, nothing happens for the event.
+   *
+   * @param aUseSystemSettings    Set the result of UseSystemScrollSettingFor().
+   */
+  PRInt32 ComputeWheelActionFor(nsMouseScrollEvent* aMouseEvent,
+                                PRBool aUseSystemSettings);
+  /**
+   * Gets the wheel action for the aMouseEvent ONLY with the pref.
+   * When you actually do something for the event, probably you should use
+   * ComputeWheelActionFor().
+   */
+  PRInt32 GetWheelActionFor(nsMouseScrollEvent* aMouseEvent);
+  /**
+   * Gets the pref value for line scroll amount for the aMouseEvent.
+   * Note that this method doesn't check whether the aMouseEvent is line scroll
+   * event and doesn't use system settings.
+   */
+  PRInt32 GetScrollLinesFor(nsMouseScrollEvent* aMouseEvent);
+  /**
+   * Whether use system scroll settings or settings in our prefs for the event.
+   * TRUE, if use system scroll settings.  Otherwise, FALSE.
+   */
+  PRBool UseSystemScrollSettingFor(nsMouseScrollEvent* aMouseEvent);
   // end mousewheel functions
 
   /*

widget/src/windows/nsWindow.cpp

@@ -6417,6 +6417,38 @@ nsWindow::OnMouseWheel(UINT aMessage, WPARAM aWParam, LPARAM aLParam,
   sLastMouseWheelUnitIsPage = isPageScroll;
   sLastMouseWheelTime = now;
 
+  *aRetValue = isVertical ? FALSE : TRUE; // means we process this message
+  nsModifierKeyState modKeyState;
+
+  // Our positive delta value means to bottom or right.
+  // But positive nativeDelta value means to top or right.
+  // Use orienter for computing our delta value.
+  PRInt32 orienter = isVertical ? -1 : 1;
+
+  // Assume the Control key is down if the Elantech touchpad has sent the
+  // mis-ordered WM_KEYDOWN/WM_MOUSEWHEEL messages.  (See the comment in
+  // OnKeyUp.)
+  PRBool isControl;
+  if (mAssumeWheelIsZoomUntil &&
+      static_cast<DWORD>(::GetMessageTime()) < mAssumeWheelIsZoomUntil) {
+    isControl = PR_TRUE;
+  } else {
+    isControl = modKeyState.mIsControlDown;
+  }
+
+  // Create line (or page) scroll event.
+  nsMouseScrollEvent scrollEvent(PR_TRUE, NS_MOUSE_SCROLL, this);
+
+  // Initialize common members on line scroll event, pixel scroll event and
+  // test event.
+  InitEvent(scrollEvent);
+  scrollEvent.isShift     = modKeyState.mIsShiftDown;
+  scrollEvent.isControl   = isControl;
+  scrollEvent.isMeta      = PR_FALSE;
+  scrollEvent.isAlt       = modKeyState.mIsAltDown;
+
+  // Before dispatching line scroll event, we should get the current scroll
+  // event target information for pixel scroll.
   PRBool dispatchPixelScrollEvent = PR_FALSE;
   PRInt32 pixelsPerUnit = 0;
 
@@ -6426,6 +6458,10 @@ nsWindow::OnMouseWheel(UINT aMessage, WPARAM aWParam, LPARAM aLParam,
     testEvent.scrollFlags = isPageScroll ? nsMouseScrollEvent::kIsFullPage : 0;
     testEvent.scrollFlags |= isVertical ? nsMouseScrollEvent::kIsVertical :
                                           nsMouseScrollEvent::kIsHorizontal;
+    testEvent.isShift     = scrollEvent.isShift;
+    testEvent.isControl   = scrollEvent.isControl;
+    testEvent.isMeta      = scrollEvent.isMeta;
+    testEvent.isAlt       = scrollEvent.isAlt;
     testEvent.delta = sLastMouseWheelDeltaIsPositive ? -1 : 1;
     nsQueryContentEvent queryEvent(PR_TRUE, NS_QUERY_SCROLL_TARGET_INFO, this);
     InitEvent(queryEvent);
@@ -6447,33 +6483,10 @@ nsWindow::OnMouseWheel(UINT aMessage, WPARAM aWParam, LPARAM aLParam,
     }
   }
 
-  *aRetValue = isVertical ? FALSE : TRUE; // means we process this message
+  // If we dispatch pixel scroll event after the line scroll event,
-  nsModifierKeyState modKeyState;
+  // we should set kHasPixels flag to the line scroll event.
-
-  // Our positive delta value means to bottom or right.
-  // But positive nativeDelta value means to top or right.
-  // Use orienter for computing our delta value.
-  PRInt32 orienter = isVertical ? -1 : 1;
-
-  // Assume the Control key is down if the Elantech touchpad has sent the
-  // mis-ordered WM_KEYDOWN/WM_MOUSEWHEEL messages.  (See the comment in
-  // OnKeyUp.)
-  PRBool isControl;
-  if (mAssumeWheelIsZoomUntil &&
-      static_cast<DWORD>(::GetMessageTime()) < mAssumeWheelIsZoomUntil) {
-    isControl = PR_TRUE;
-  } else {
-    isControl = modKeyState.mIsControlDown;
-  }
-
-  nsMouseScrollEvent scrollEvent(PR_TRUE, NS_MOUSE_SCROLL, this);
-  InitEvent(scrollEvent);
   scrollEvent.scrollFlags =
     dispatchPixelScrollEvent ? nsMouseScrollEvent::kHasPixels : 0;
-  scrollEvent.isShift     = modKeyState.mIsShiftDown;
-  scrollEvent.isControl   = isControl;
-  scrollEvent.isMeta      = PR_FALSE;
-  scrollEvent.isAlt       = modKeyState.mIsAltDown;
 
   PRInt32 nativeDeltaForScroll = nativeDelta + sRemainingDeltaForScroll;
 
@@ -6521,10 +6534,11 @@ nsWindow::OnMouseWheel(UINT aMessage, WPARAM aWParam, LPARAM aLParam,
   InitEvent(pixelEvent);
   pixelEvent.scrollFlags = nsMouseScrollEvent::kAllowSmoothScroll |
     (scrollEvent.scrollFlags & ~nsMouseScrollEvent::kHasPixels);
-  pixelEvent.isShift     = modKeyState.mIsShiftDown;
+  // Use same modifier state for pixel scroll event.
-  pixelEvent.isControl   = modKeyState.mIsControlDown;
+  pixelEvent.isShift     = scrollEvent.isShift;
-  pixelEvent.isMeta      = PR_FALSE;
+  pixelEvent.isControl   = scrollEvent.isControl;
-  pixelEvent.isAlt       = modKeyState.mIsAltDown;
+  pixelEvent.isMeta      = scrollEvent.isMeta;
+  pixelEvent.isAlt       = scrollEvent.isAlt;
 
   PRInt32 nativeDeltaForPixel = nativeDelta + sRemainingDeltaForPixel;