chxavcompositecommand.cpp

来自「symbian 下的helix player源代码」· C++ 代码 · 共 89 行

/************************************************************************
 * chxavcompositecommand.cpp
 * -------------------------
 *
 * Synopsis:
 * 
 *
 * Implementation of aggregated command object
 *
 * commands (actions) are executed in order of addition
 * copying the command object implies sharing a reference to the aggregated list
 *
 * Target:
 * Symbian OS
 *
 *
 * (c) 1995-2003 RealNetworks, Inc. Patents pending. All rights reserved.
 *
 ************************************************************************/ 

// Symbian includes...
#include <e32std.h>

// Include from this project...
#include "chxavcompositecommand.h"

CHXAvCompositeCommand::CHXAvCompositeCommand(const CHXAvCompositeCommand& rhs) :
    m_nextId(rhs.m_nextId)
{
    // Copy the command list
    LISTPOSITION pos = rhs.m_commands.GetHeadPosition();
    while (pos != NULL)
    {
	CHXAvCommand *ptr = (CHXAvCommand *)rhs.m_commands.GetNext(pos);
	AppendL(*ptr);
    }
}

CHXAvCompositeCommand::~CHXAvCompositeCommand()
{
    LISTPOSITION pos = m_commands.GetHeadPosition();
    while (pos != NULL)
    {
	CHXAvCommand *ptr = (CHXAvCommand *)m_commands.GetNext(pos);
	delete ptr;
    }
}

////////////////////////////////////////
// add an action; becomes last command to be executed
// return id that can be used to remove command
// later on
//
CHXAvCompositeCommand::CID CHXAvCompositeCommand::AppendL(const CHXAvCommand& cmd)
{
    CHXAvCommand *pCmd = cmd.CloneL();
    m_commands.AddTail(pCmd);
    return pCmd;
}

////////////////////////////////////////
// add an action; becomes last command to be executed
//
void CHXAvCompositeCommand::Remove(CID idCommand)
{
    LISTPOSITION pos = m_commands.Find(idCommand, NULL);
    if (pos != NULL)
	m_commands.RemoveAt(pos);
    delete (CHXAvCommand *)idCommand;
}


////////////////////////////////////////
// go through list of commands and execute each
// in order they were added
void CHXAvCompositeCommand::Execute()
{
    LISTPOSITION pos = m_commands.GetHeadPosition();
    while (pos != NULL)
    {
	CHXAvCommand *ptr = (CHXAvCommand *)m_commands.GetNext(pos);
	if (ptr != NULL)
	    ptr->Execute();
    }
    
}