blob: b1f3cb216dedb27d3875ce2a97fd8f6f1ba90c08 [file] [log] [blame]
// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#import "ui/views/cocoa/cocoa_mouse_capture.h"
#import <Cocoa/Cocoa.h>
#include "base/logging.h"
#include "base/macros.h"
#include "ui/base/cocoa/weak_ptr_nsobject.h"
#import "ui/views/cocoa/cocoa_mouse_capture_delegate.h"
namespace views {
// The ActiveEventTap is a RAII handle on the resources being used to capture
// events. There is either 0 or 1 active instance of this class. If a second
// instance is created, it will destroy the other instance before returning from
// its constructor.
class CocoaMouseCapture::ActiveEventTap {
public:
explicit ActiveEventTap(CocoaMouseCapture* owner);
~ActiveEventTap();
// Returns the NSWindow with capture or nil if no window has capture
// currently.
static NSWindow* GetGlobalCaptureWindow();
void Init();
private:
// Returns the associated NSWindow with capture.
NSWindow* GetCaptureWindow() const;
// The currently active event tap, or null if there is none.
static ActiveEventTap* g_active_event_tap;
CocoaMouseCapture* owner_; // Weak. Owns this.
id local_monitor_;
id global_monitor_;
ui::WeakPtrNSObjectFactory<CocoaMouseCapture> factory_;
DISALLOW_COPY_AND_ASSIGN(ActiveEventTap);
};
CocoaMouseCapture::ActiveEventTap*
CocoaMouseCapture::ActiveEventTap::g_active_event_tap = nullptr;
CocoaMouseCapture::ActiveEventTap::ActiveEventTap(CocoaMouseCapture* owner)
: owner_(owner),
local_monitor_(nil),
global_monitor_(nil),
factory_(owner) {
if (g_active_event_tap)
g_active_event_tap->owner_->OnOtherClientGotCapture();
DCHECK(!g_active_event_tap);
g_active_event_tap = this;
}
CocoaMouseCapture::ActiveEventTap::~ActiveEventTap() {
DCHECK_EQ(g_active_event_tap, this);
[NSEvent removeMonitor:global_monitor_];
[NSEvent removeMonitor:local_monitor_];
g_active_event_tap = nullptr;
owner_->delegate_->OnMouseCaptureLost();
}
// static
NSWindow* CocoaMouseCapture::ActiveEventTap::GetGlobalCaptureWindow() {
return g_active_event_tap ? g_active_event_tap->GetCaptureWindow() : nil;
}
void CocoaMouseCapture::ActiveEventTap::Init() {
// Consume most things, but not NSMouseEntered/Exited: The Widget doing
// capture will still see its own Entered/Exit events, but not those for other
// NSViews, since consuming those would break their tracking area logic.
NSEventMask event_mask =
NSLeftMouseDownMask | NSLeftMouseUpMask | NSRightMouseDownMask |
NSRightMouseUpMask | NSMouseMovedMask | NSLeftMouseDraggedMask |
NSRightMouseDraggedMask | NSScrollWheelMask | NSOtherMouseDownMask |
NSOtherMouseUpMask | NSOtherMouseDraggedMask;
// Capture a WeakPtr via NSObject. This allows the block to detect another
// event monitor for the same event deleting |owner_|.
WeakPtrNSObject* handle = factory_.handle();
auto local_block = ^NSEvent*(NSEvent* event) {
CocoaMouseCapture* owner =
ui::WeakPtrNSObjectFactory<CocoaMouseCapture>::Get(handle);
if (owner)
owner->delegate_->PostCapturedEvent(event);
return nil; // Swallow all local events.
};
auto global_block = ^void(NSEvent* event) {
CocoaMouseCapture* owner =
ui::WeakPtrNSObjectFactory<CocoaMouseCapture>::Get(handle);
if (owner)
owner->delegate_->PostCapturedEvent(event);
};
local_monitor_ = [NSEvent addLocalMonitorForEventsMatchingMask:event_mask
handler:local_block];
global_monitor_ =
[NSEvent addGlobalMonitorForEventsMatchingMask:event_mask
handler:global_block];
}
NSWindow* CocoaMouseCapture::ActiveEventTap::GetCaptureWindow() const {
return owner_->delegate_->GetWindow();
}
CocoaMouseCapture::CocoaMouseCapture(CocoaMouseCaptureDelegate* delegate)
: delegate_(delegate), active_handle_(new ActiveEventTap(this)) {
active_handle_->Init();
}
CocoaMouseCapture::~CocoaMouseCapture() {}
// static
NSWindow* CocoaMouseCapture::GetGlobalCaptureWindow() {
return ActiveEventTap::GetGlobalCaptureWindow();
}
void CocoaMouseCapture::OnOtherClientGotCapture() {
DCHECK(active_handle_);
active_handle_.reset();
}
} // namespace views