chxavactivewatcher.h

来自「symbian 下的helix player源代码」· C头文件 代码 · 共 92 行

/************************************************************************
 * chxavactivewatcher.h
 * --------------------
 *
 * Synopsis:
 *
 * base class for classes that request active object
 * event notification from system services
 *
 *
 *
 * (c) 1995-2003 RealNetworks, Inc. Patents pending. All rights reserved.
 *
 ************************************************************************/ 
#ifndef _chxavactivewatcher_h_
#define _chxavactivewatcher_h_

// Include from this project...
#include "chxavcommand.h"
#include "chxavactivecompletiondispatch.h"
#include "chxavcallback.h"


// class CHXAvActiveWatcher
class CHXAvActiveWatcher
{
protected:
// ctor and dtor
    CHXAvActiveWatcher();
    virtual ~CHXAvActiveWatcher();

    void BaseConstructL(TInt activePriority = CActive::EPriorityStandard);

private:
// disallow assignment and copy
    CHXAvActiveWatcher(const CHXAvActiveWatcher& rhs);
    CHXAvActiveWatcher& operator=(const CHXAvActiveWatcher& rhs);

public:
// methods
    void SetEventActionL(const CHXAvCommand& cmd);
    void SetNotificationDelay(TUint msDelay);
    void WatchForNextEvent();
    void StartWatching();
    void StopWatching();
    bool IsWatching() const;

protected:
// implementation
    virtual void OnEvent(TInt status);
    virtual void OnCancelWatch(TInt status);
    virtual void ForwardEvent();

    virtual void DoIssueRequest(const CHXAvActiveCmplPtr& spActive) = 0;
    virtual void DoCancelRequest(const CHXAvActiveCmplPtr& spActive) = 0;

private:
// data
    CHXAvActiveCmplPtr	m_spWatchObject;
    bool		m_bKeepWatching;
    CHXAvCommandPtr	m_spEventHandler;
    CHXAvCallback          m_cbFowardEvent;
    TUint               m_msForwardEventDelay;
};

////////////////////////////////////////////
// set the handler action to execute upon filesystem event
inline
void CHXAvActiveWatcher::SetEventActionL(const CHXAvCommand& cmd)
{
    m_spEventHandler = cmd.CloneL();
}

////////////////////////////////////////////
//
inline
bool CHXAvActiveWatcher::IsWatching() const
{
    return m_spWatchObject->IsActive() || m_cbFowardEvent.IsPending();
}

////////////////////////////////////////////
//
inline
void CHXAvActiveWatcher::SetNotificationDelay(TUint msDelay)
{
    m_msForwardEventDelay = msDelay;
}

#endif // _chxavactivewatcher_h_