Mac Panels interaction with Dock modifications. (step 1)

chrome/browser/ui/panels/panel_titlebar_view_cocoa.mm

Index: chrome/browser/ui/panels/panel_titlebar_view_cocoa.mm
diff --git a/chrome/browser/ui/panels/panel_titlebar_view_cocoa.mm b/chrome/browser/ui/panels/panel_titlebar_view_cocoa.mm
index 293855b8e9a0a4e18c0fdb9c4576e88e892cc20b..add4c4ce42360bd6c4659bcc04a0911802545f09 100644
--- a/chrome/browser/ui/panels/panel_titlebar_view_cocoa.mm
+++ b/chrome/browser/ui/panels/panel_titlebar_view_cocoa.mm
@@ -24,6 +24,11 @@ const int kRoundedCornerSize = 3;
 const int kButtonPadding = 8;
 const int kIconAndTextPadding = 5;
 
+// Square of a distance that user needs to move the mouse in order to start the
+// drag. Threshold is needed to differentiate drags from attempts to click the
+// titlebar with a twitch of the mouse pointer.
+const int kDragThreasholdSquared = 9;

[jennb, 2011/11/17 23:45:40]

typo: Threshold

What's the logic behind using the square of the distance?

[Dmitry Titov, 2011/11/18 00:15:11]

I'm computing a distance and don't want to do sqrt...

+
 // Used to implement TestingAPI
 static NSEvent* MakeMouseEvent(NSEventType type,
                                NSPoint point,
@@ -317,6 +322,7 @@ static NSEvent* MakeMouseEvent(NSEventType type,
 
 - (void)mouseDown:(NSEvent*)event {
   dragState_ = PANEL_DRAG_CAN_START;
+  dragStartLocation_ = [event locationInWindow];
 }
 
 - (void)mouseUp:(NSEvent*)event {
@@ -326,6 +332,12 @@ static NSEvent* MakeMouseEvent(NSEventType type,
     [controller_ onTitlebarMouseClicked];
 }
 
+- (BOOL)overDragThreshold:(NSPoint)mouseLocation {

[jennb, 2011/11/17 23:45:40]

exceedsDragThreshold? I'm not sure what overDragThreshold means.

[Dmitry Titov, 2011/11/18 00:15:11]

Done.

+  float deltaX = dragStartLocation_.x - mouseLocation.x;
+  float deltaY = dragStartLocation_.y - mouseLocation.y;
+  return deltaX*deltaX + deltaY*deltaY > kDragThreasholdSquared;

[jennb, 2011/11/17 23:45:40]

Please use parens rather than dropping the spacing around operators if you want
to make precedence more obvious.

[Dmitry Titov, 2011/11/18 00:15:11]

Done.

+}
+
 - (void)mouseDragged:(NSEvent*)event {
   // In addition to events needed to control the drag operation, fetch the right
   // mouse click events and key down events and ignore them, to prevent their
@@ -345,8 +357,12 @@ static NSEvent* MakeMouseEvent(NSEventType type,
 
     switch ([event type]) {
       case NSLeftMouseDragged:
-        if (dragState_ == PANEL_DRAG_CAN_START)
-          [self startDrag];
+        if (dragState_ == PANEL_DRAG_CAN_START) {
+          if ([self overDragThreshold:[event locationInWindow]])

[jennb, 2011/11/17 23:45:40]

nit: How about reversing this conditional to make code easier to read?

[Dmitry Titov, 2011/11/18 00:15:11]

Done.

+            [self startDrag];
+          else
+            return;  // Don't start real drag yet.
+        }
         [self dragWithDeltaX:[event deltaX]];
         break;
 
@@ -358,6 +374,10 @@ static NSEvent* MakeMouseEvent(NSEventType type,
         break;
 
       case NSLeftMouseUp:
+        if (dragState_ == PANEL_DRAG_CAN_START) {  // Drag didn't really start.
+          [self mouseUp:event];
+          return;

[jennb, 2011/11/17 23:45:40]

nit: I want to drop this return and add else clause around the last 2 lines.

[Dmitry Titov, 2011/11/18 00:15:11]

Done.

+        }
         [self endDrag:NO];
         keepGoing = NO;
         break;