* Extended the Desktop's MouseFilter to reset the mouse-down messages' "clicks"

field. It does that when the modifiers, the pressed buttons, or the click
  target changes between the clicks, or when the distance between the click
  points is >= four pixels.
* Adjusted the Window::MouseDown() and WindowBehavior::MouseDown() interfaces
  and implementation accordingly (we now also pass and return click count and
  click targets).
* Removed the no longer need multi-click handling from DefaultWindowBehaviour.

Fixes #6841 and #6867.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@39623 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/servers/app/ClickTarget.h

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2010, Ingo Weinhold, [email protected].
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef CLICK_TARGET_H
+#define CLICK_TARGET_H
+
+
+#include <TokenSpace.h>
+
+
+/*!	\brief Identifies a mouse click target in the app server.
+
+	Used to discriminate between different targets in order to filter
+	multi-clicks. A click on a different target resets the click count.
+*/
+struct ClickTarget {
+public:
+	enum Type {
+		TYPE_INVALID,
+		TYPE_WINDOW_CONTENTS,
+		TYPE_WINDOW_DECORATOR
+	};
+
+public:
+	ClickTarget()
+		:
+		fType(TYPE_INVALID),
+		fWindow(B_NULL_TOKEN),
+		fWindowElement(0)
+	{
+	}
+
+	ClickTarget(Type type, int32 window, int32 windowElement)
+		:
+		fType(type),
+		fWindow(window),
+		fWindowElement(windowElement)
+	{
+	}
+
+	bool IsValid() const
+	{
+		return fType != TYPE_INVALID;
+	}
+
+	Type GetType() const
+	{
+		return fType;
+	}
+
+	int32 WindowToken() const
+	{
+		return fWindow;
+	}
+
+	int32 WindowElement() const
+	{
+		return fWindowElement;
+	}
+
+	bool operator==(const ClickTarget& other) const
+	{
+		return fType == other.fType && fWindow == other.fWindow
+			&& fWindowElement == other.fWindowElement;
+	}
+
+	bool operator!=(const ClickTarget& other) const
+	{
+		return !(*this == other);
+	}
+
+private:
+	Type	fType;
+	int32	fWindow;
+	int32	fWindowElement;
+};
+
+
+#endif	// CLICK_TARGET_H

src/servers/app/DefaultWindowBehaviour.cpp

@@ -19,6 +19,7 @@
 
 #include <WindowPrivate.h>
 
+#include "ClickTarget.h"
 #include "Desktop.h"
 #include "DrawingEngine.h"
 #include "Window.h"
@@ -120,8 +121,7 @@ struct DefaultWindowBehaviour::MouseTrackingState : State {
 			fMinimizeCheckOnMouseUp = false;
 			if (message->FindInt32("modifiers") == fBehavior.fLastModifiers
 				&& (fWindow->Flags() & B_NOT_MINIMIZABLE) == 0
-				&& system_time() - fLastMoveTime
-					< kWindowActivationTimeout) {
+				&& system_time() - fLastMoveTime < kWindowActivationTimeout) {
 				fWindow->ServerWindow()->NotifyMinimize(true);
 			}
 		}
@@ -629,10 +629,7 @@ DefaultWindowBehaviour::DefaultWindowBehaviour(Window* window)
 	fWindow(window),
 	fDesktop(window->Desktop()),
 	fState(NULL),
-	fLastModifiers(0),
-	fLastMouseButtons(0),
-	fLastRegion(REGION_NONE),
-	fResetClickCount(0)
+	fLastModifiers(0)
 {
 }
 
@@ -644,30 +641,12 @@ DefaultWindowBehaviour::~DefaultWindowBehaviour()
 
 
 bool
-DefaultWindowBehaviour::MouseDown(BMessage* message, BPoint where)
+DefaultWindowBehaviour::MouseDown(BMessage* message, BPoint where,
+	int32 lastHitRegion, int32& clickCount, int32& _hitRegion)
 {
-	// Get the click count and reset it, if the modifiers changed in the
-	// meantime. Do the same when this is not the button we've seen before.
-	// TODO: At least the modifier check should be done in a better place
-	// (e.g. the input server). It should also reset clicks after mouse
-	// movement (which we don't do here either -- though that's probably
-	// acceptable).
-	int32 clickCount = message->FindInt32("clicks");
-	int32 modifiers = message->FindInt32("modifiers");
+	fLastModifiers = message->FindInt32("modifiers");
 	int32 buttons = message->FindInt32("buttons");
 
-	if (clickCount <= 1) {
-		fResetClickCount = 0;
-	} else if (modifiers != fLastModifiers || buttons != fLastMouseButtons
-		|| clickCount - fResetClickCount < 1) {
-		fResetClickCount = clickCount - 1;
-		clickCount = 1;
-	} else
-		clickCount -= fResetClickCount;
-
-	fLastModifiers = modifiers;
-	fLastMouseButtons = buttons;
-
 	// if a state is active, let it do the job
 	if (fState != NULL)
 		return fState->MouseDown(message, where);
@@ -683,7 +662,7 @@ DefaultWindowBehaviour::MouseDown(BMessage* message, BPoint where)
 	if (decorator != NULL)
 		inBorderRegion = decorator->GetFootprint().Contains(where);
 
-	bool windowModifier = _IsWindowModifier(modifiers);
+	bool windowModifier = _IsWindowModifier(fLastModifiers);
 
 	if (windowModifier || inBorderRegion) {
 		// click on the window decorator or we have the window modifier keys
@@ -712,7 +691,7 @@ DefaultWindowBehaviour::MouseDown(BMessage* message, BPoint where)
 					// tab sliding in any case if either shift key is held down
 					// except sliding up-down by moving mouse left-right would
 					// look strange
-					if ((modifiers & B_SHIFT_KEY) != 0
+					if ((fLastModifiers & B_SHIFT_KEY) != 0
 						&& fWindow->Look() != kLeftTitledWindowLook) {
 						action = ACTION_SLIDE_TAB;
 						break;
@@ -762,15 +741,7 @@ DefaultWindowBehaviour::MouseDown(BMessage* message, BPoint where)
 		}
 	}
 
-	// The hit region changed since the last the click. Reset the click count.
-	if (hitRegion != fLastRegion) {
-		fLastRegion = hitRegion;
-		clickCount = 1;
-
-		fResetClickCount = message->FindInt32("clicks") - 1;
-		if (fResetClickCount < 0)
-			fResetClickCount = 0;
-	}
+	_hitRegion = (int32)hitRegion;
 
 	if (action == ACTION_NONE) {
 		// No action -- if this is a click inside the window's contents,
@@ -778,6 +749,10 @@ DefaultWindowBehaviour::MouseDown(BMessage* message, BPoint where)
 		return inBorderRegion;
 	}
 
+	// reset the click count, if the hit region differs from the previous one
+	if (hitRegion != lastHitRegion)
+		clickCount = 1;
+
 	DesktopSettings desktopSettings(fDesktop);
 	if (!desktopSettings.AcceptFirstClick()) {
 		// Ignore clicks on decorator buttons if the

src/servers/app/DefaultWindowBehaviour.h

@@ -29,7 +29,9 @@ public:
 								DefaultWindowBehaviour(Window* window);
 	virtual						~DefaultWindowBehaviour();
 
-	virtual	bool				MouseDown(BMessage* message, BPoint where);
+	virtual	bool				MouseDown(BMessage* message, BPoint where,
+									int32 lastHitRegion, int32& clickCount,
+									int32& _hitRegion);
 	virtual	void				MouseUp(BMessage* message, BPoint where);
 	virtual	void				MouseMoved(BMessage *message, BPoint where,
 									bool isFake);
@@ -38,7 +40,7 @@ public:
 
 private:
 			enum Region {
-				REGION_NONE,
+				REGION_NONE = 0,
 
 				REGION_TAB,
 				REGION_BORDER,
@@ -90,9 +92,6 @@ protected:
 			Desktop*			fDesktop;
 			State*				fState;
 			int32				fLastModifiers;
-			int32				fLastMouseButtons;
-			Region				fLastRegion;
-			int32				fResetClickCount;
 };
 
 

src/servers/app/Desktop.cpp

@@ -36,6 +36,7 @@
 #include <WindowInfo.h>
 
 #include "AppServer.h"
+#include "ClickTarget.h"
 #include "DecorManager.h"
 #include "DesktopSettingsPrivate.h"
 #include "DrawingEngine.h"
@@ -65,6 +66,20 @@
 #endif
 
 
+static inline float
+square_vector_length(float x, float y)
+{
+	return x * x + y * y;
+}
+
+
+static inline float
+square_distance(const BPoint& a, const BPoint& b)
+{
+	return square_vector_length(a.x - b.x, a.y - b.y);
+}
+
+
 class KeyboardFilter : public EventFilter {
 	public:
 		KeyboardFilter(Desktop* desktop);
@@ -83,14 +98,19 @@ class KeyboardFilter : public EventFilter {
 
 
 class MouseFilter : public EventFilter {
-	public:
-		MouseFilter(Desktop* desktop);
+public:
+	MouseFilter(Desktop* desktop);
 
-		virtual filter_result Filter(BMessage* message, EventTarget** _target,
-			int32* _viewToken, BMessage* latestMouseMoved);
+	virtual filter_result Filter(BMessage* message, EventTarget** _target,
+		int32* _viewToken, BMessage* latestMouseMoved);
 
-	private:
-		Desktop*	fDesktop;
+private:
+	Desktop*	fDesktop;
+	int32		fLastClickButtons;
+	int32		fLastClickModifiers;
+	int32		fResetClickCount;
+	BPoint		fLastClickPoint;
+	ClickTarget	fLastClickTarget;
 };
 
 
@@ -218,7 +238,12 @@ KeyboardFilter::RemoveTarget(EventTarget* target)
 
 MouseFilter::MouseFilter(Desktop* desktop)
 	:
-	fDesktop(desktop)
+	fDesktop(desktop),
+	fLastClickButtons(0),
+	fLastClickModifiers(0),
+	fResetClickCount(0),
+	fLastClickPoint(),
+	fLastClickTarget()
 {
 }
 
@@ -248,9 +273,66 @@ MouseFilter::Filter(BMessage* message, EventTarget** _target, int32* _viewToken,
 		// dispatch event to the window
 		switch (message->what) {
 			case B_MOUSE_DOWN:
-				window->MouseDown(message, where, &viewToken);
+			{
+				int32 windowToken = window->ServerWindow()->ServerToken();
+
+				// First approximation of click count validation. We reset the
+				// click count when modifiers or pressed buttons have changed
+				// or when we've got a different click target, or when the
+				// previous click location is too far from the new one. We can
+				// only check the window of the click target here; we'll recheck
+				// after asking the window.
+				int32 modifiers = message->FindInt32("modifiers");
+
+				int32 originalClickCount = message->FindInt32("clicks");
+				if (originalClickCount <= 0)
+					originalClickCount = 1;
+
+				int32 clickCount = originalClickCount;
+				if (clickCount > 1) {
+					if (modifiers != fLastClickModifiers
+						|| buttons != fLastClickButtons
+						|| !fLastClickTarget.IsValid()
+						|| fLastClickTarget.WindowToken() != windowToken
+						|| square_distance(where, fLastClickPoint) >= 16
+						|| clickCount - fResetClickCount < 1) {
+						clickCount = 1;
+					} else
+						clickCount -= fResetClickCount;
+				}
+
+				// notify the window
+				ClickTarget clickTarget;
+				window->MouseDown(message, where, fLastClickTarget, clickCount,
+					clickTarget);
+
+				// If the click target changed, always reset the click count.
+				if (clickCount != 1 && clickTarget != fLastClickTarget)
+					clickCount = 1;
+
+				// update our click count management attributes
+				fResetClickCount = originalClickCount - clickCount;
+				fLastClickTarget = clickTarget;
+				fLastClickButtons = buttons;
+				fLastClickModifiers = modifiers;
+				fLastClickPoint = where;
+
+				// get the view token from the click target
+				if (clickTarget.GetType() == ClickTarget::TYPE_WINDOW_CONTENTS)
+					viewToken = clickTarget.WindowElement();
+
+				// update the message's "clicks" field, if necessary
+				if (clickCount != originalClickCount) {
+					if (message->HasInt32("clicks"))
+						message->ReplaceInt32("clicks", clickCount);
+					else
+						message->AddInt32("clicks", clickCount);
+				}
+
+				// notify desktop listeners
 				fDesktop->NotifyMouseDown(window, message, where);
 				break;
+			}
 
 			case B_MOUSE_UP:
 				window->MouseUp(message, where, &viewToken);
@@ -273,6 +355,13 @@ MouseFilter::Filter(BMessage* message, EventTarget** _target, int32* _viewToken,
 			*_viewToken = viewToken;
 			*_target = &window->EventTarget();
 		}
+	} else if (message->what == B_MOUSE_DOWN) {
+		// the mouse-down didn't hit a window -- reset the click target
+		fResetClickCount = 0;
+		fLastClickTarget = ClickTarget();
+		fLastClickButtons = message->FindInt32("buttons");
+		fLastClickModifiers = message->FindInt32("modifiers");
+		fLastClickPoint = where;
 	}
 
 	if (window == NULL || viewToken == B_NULL_TOKEN) {

src/servers/app/Window.cpp

@@ -14,6 +14,7 @@
 
 #include "Window.h"
 
+#include "ClickTarget.h"
 #include "Decorator.h"
 #include "DecorManager.h"
 #include "Desktop.h"
@@ -781,14 +782,47 @@ Window::EnableUpdateRequests()
 // #pragma mark -
 
 
-void
-Window::MouseDown(BMessage* message, BPoint where, int32* _viewToken)
-{
-	DesktopSettings desktopSettings(fDesktop);
+/*!	\brief Handles a mouse-down message for the window.
 
-	bool eventEaten = fWindowBehaviour->MouseDown(message, where);
-	if (!eventEaten) {
+	\param message The message.
+	\param where The point where the mouse click happened.
+	\param lastClickTarget The target of the previous click.
+	\param clickCount The number of subsequent, no longer than double-click
+		interval separated clicks that have happened so far. This number doesn't
+		necessarily match the value in the message. It has already been
+		pre-processed in order to avoid erroneous multi-clicks (e.g. when a
+		different button has been used or a different window was targeted). This
+		is an in-out variable. The method can reset the value to 1, if it
+		doesn't want this event handled as a multi-click. Returning a different
+		click target will also make the caller reset the click count.
+	\param _clickTarget Set by the method to a value identifying the clicked
+		element. If not explicitly set, an invalid click target is assumed.
+*/
+void
+Window::MouseDown(BMessage* message, BPoint where,
+	const ClickTarget& lastClickTarget, int32& clickCount,
+	ClickTarget& _clickTarget)
+{
+	// If the previous click hit our decorator, get the hit region.
+	int32 windowToken = fWindow->ServerToken();
+	int32 lastHitRegion = 0;
+	if (lastClickTarget.GetType() == ClickTarget::TYPE_WINDOW_DECORATOR
+		&& lastClickTarget.WindowToken() == windowToken) {
+		lastHitRegion = lastClickTarget.WindowElement();
+	}
+
+	// Let the window behavior process the mouse event.
+	int32 hitRegion = 0;
+	bool eventEaten = fWindowBehaviour->MouseDown(message, where, lastHitRegion,
+		clickCount, hitRegion);
+
+	if (eventEaten) {
+		// click on the decorator (or equivalent)
+		_clickTarget = ClickTarget(ClickTarget::TYPE_WINDOW_DECORATOR,
+			windowToken, (int32)hitRegion);
+	} else {
 		// click was inside the window contents
+		int32 viewToken = B_NULL_TOKEN;
 		if (View* view = ViewAt(where)) {
 			if (HasModal())
 				return;
@@ -801,6 +835,7 @@ Window::MouseDown(BMessage* message, BPoint where, int32* _viewToken)
 
 				// Activate or focus the window in case it doesn't accept first
 				// click, depending on the mouse mode
+				DesktopSettings desktopSettings(fDesktop);
 				if (desktopSettings.MouseMode() == B_NORMAL_MOUSE
 					&& !acceptFirstClick)
 					fDesktop->ActivateWindow(this);
@@ -819,9 +854,12 @@ Window::MouseDown(BMessage* message, BPoint where, int32* _viewToken)
 			}
 
 			// fill out view token for the view under the mouse
-			*_viewToken = view->Token();
+			viewToken = view->Token();
 			view->MouseDown(message, where);
 		}
+
+		_clickTarget = ClickTarget(ClickTarget::TYPE_WINDOW_CONTENTS,
+			windowToken, viewToken);
 	}
 }
 

src/servers/app/Window.h

@@ -27,6 +27,7 @@ namespace BPrivate {
 	class PortLink;
 };
 
+class ClickTarget;
 class ClientLooper;
 class Decorator;
 class Desktop;
@@ -144,7 +145,9 @@ public:
 									int32 xOffset, int32 yOffset);
 
 			void				MouseDown(BMessage* message, BPoint where,
-									int32* _viewToken);
+									const ClickTarget& lastClickTarget,
+									int32& clickCount,
+									ClickTarget& _clickTarget);
 			void				MouseUp(BMessage* message, BPoint where,
 									int32* _viewToken);
 			void				MouseMoved(BMessage* message, BPoint where,

src/servers/app/WindowBehaviour.cpp

@@ -27,3 +27,29 @@ void
 WindowBehaviour::ModifiersChanged(int32 modifiers)
 {
 }
+
+
+/*!	\fn WindowBehaviour::MouseDown()
+	\brief Handles a mouse-down message for the window.
+
+	Note that values passed and returned for the hit regions are only meaningful
+	to the WindowBehavior subclass, save for the value 0, which is refers to an
+	invalid region.
+
+	\param message The message.
+	\param where The point where the mouse click happened.
+	\param lastHitRegion The hit region of the previous click.
+	\param clickCount The number of subsequent, no longer than double-click
+		interval separated clicks that have happened so far. This number doesn't
+		necessarily match the value in the message. It has already been
+		pre-processed in order to avoid erroneous multi-clicks (e.g. when a
+		different button has been used or a different window was targeted). This
+		is an in-out variable. The method can reset the value to 1, if it
+		doesn't want this event handled as a multi-click. Returning a different
+		click hit region will also make the caller reset the click count.
+	\param _hitRegion Set by the method to a value identifying the clicked
+		decorator element. If not explicitly set, an invalid hit region (0) is
+		assumed. Only needs to be set when returning \c true.
+	\return \c true, if the event was a WindowBehaviour event and should be
+		discarded.
+*/

src/servers/app/WindowBehaviour.h

@@ -11,8 +11,11 @@
 
 #include <Region.h>
 
+#include "Decorator.h"
+
 
 class BMessage;
+class ClickTarget;
 
 
 class WindowBehaviour {
@@ -20,8 +23,9 @@ public:
 								WindowBehaviour();
 	virtual						~WindowBehaviour();
 
-	//! \return true if event was a WindowBehaviour event and should be discard
-	virtual	bool				MouseDown(BMessage* message, BPoint where) = 0;
+	virtual	bool				MouseDown(BMessage* message, BPoint where,
+									int32 lastHitRegion, int32& clickCount,
+									int32& _hitRegion) = 0;
 	virtual	void				MouseUp(BMessage* message, BPoint where) = 0;
 	virtual	void				MouseMoved(BMessage *message, BPoint where,
 									bool isFake) = 0;