WindowMessageBroadcaster.cpp [plain text]
#include "config.h"
#include "WindowMessageBroadcaster.h"
#include "WindowMessageListener.h"
namespace WebCore {
typedef HashMap<HWND, WindowMessageBroadcaster*> InstanceMap;
static InstanceMap& instancesMap()
{
static InstanceMap instances;
return instances;
}
void WindowMessageBroadcaster::addListener(HWND hwnd, WindowMessageListener* listener)
{
WindowMessageBroadcaster* broadcaster = instancesMap().get(hwnd);
if (!broadcaster) {
broadcaster = new WindowMessageBroadcaster(hwnd);
instancesMap().add(hwnd, broadcaster);
}
broadcaster->addListener(listener);
}
void WindowMessageBroadcaster::removeListener(HWND hwnd, WindowMessageListener* listener)
{
WindowMessageBroadcaster* broadcaster = instancesMap().get(hwnd);
if (!broadcaster)
return;
broadcaster->removeListener(listener);
}
WindowMessageBroadcaster::WindowMessageBroadcaster(HWND hwnd)
: m_subclassedWindow(hwnd)
, m_originalWndProc(0)
{
ASSERT_ARG(hwnd, IsWindow(hwnd));
}
WindowMessageBroadcaster::~WindowMessageBroadcaster()
{
}
void WindowMessageBroadcaster::addListener(WindowMessageListener* listener)
{
if (m_listeners.isEmpty()) {
ASSERT(!m_originalWndProc);
#pragma warning(disable: 4244 4312)
m_originalWndProc = reinterpret_cast<WNDPROC>(SetWindowLongPtr(m_subclassedWindow, GWLP_WNDPROC, reinterpret_cast<LONG_PTR>(SubclassedWndProc)));
}
m_listeners.add(listener);
}
void WindowMessageBroadcaster::removeListener(WindowMessageListener* listener)
{
ListenerSet::iterator found = m_listeners.find(listener);
if (found == m_listeners.end())
return;
m_listeners.remove(found);
if (m_listeners.isEmpty())
destroy();
}
void WindowMessageBroadcaster::destroy()
{
m_listeners.clear();
unsubclassWindow();
instancesMap().remove(m_subclassedWindow);
delete this;
}
void WindowMessageBroadcaster::unsubclassWindow()
{
SetWindowLongPtr(m_subclassedWindow, GWLP_WNDPROC, reinterpret_cast<LONG_PTR>(m_originalWndProc));
m_originalWndProc = 0;
}
LRESULT CALLBACK WindowMessageBroadcaster::SubclassedWndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
WindowMessageBroadcaster* broadcaster = instancesMap().get(hwnd);
ASSERT(broadcaster);
ListenerSet::const_iterator end = broadcaster->listeners().end();
for (ListenerSet::const_iterator it = broadcaster->listeners().begin(); it != end; ++it)
(*it)->windowReceivedMessage(hwnd, message, wParam, lParam);
WNDPROC originalWndProc = broadcaster->originalWndProc();
if (message == WM_DESTROY)
broadcaster->destroy();
return CallWindowProc(originalWndProc, hwnd, message, wParam, lParam);
}
}