mcisampledlg.cpp

C++编程实践与技巧一书各章节的源码

// MCISampleDlg.cpp : implementation file
//
#include "stdafx.h"
#include "MCISample.h"
#include "MCISampleDlg.h"

#include <dbt.h>

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////


/////////////////////////////////////////////////////////////////////////////
// CMCISampleDlg dialog

CMCISampleDlg::CMCISampleDlg(CWnd* pParent /*=NULL*/)
	: CDialog(CMCISampleDlg::IDD, pParent)
{
	//{{AFX_DATA_INIT(CMCISampleDlg)
	m_strTrack = _T("");
	//}}AFX_DATA_INIT
	// Note that LoadIcon does not require a subsequent DestroyIcon in Win32
	m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
}

void CMCISampleDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CMCISampleDlg)
	DDX_Control(pDX, IDC_EJECT, m_btnEject);
	DDX_Control(pDX, IDC_PLAY, m_btnPlay);
	DDX_Control(pDX, IDC_STOP, m_btnStop);
	DDX_Control(pDX, IDC_PAUSE, m_btnPause);
	DDX_Control(pDX, IDC_STATUS, m_wndStatus);
	DDX_Control(pDX, IDC_TRACKSELECT, m_comboTrack);
	DDX_CBString(pDX, IDC_TRACKSELECT, m_strTrack);
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CMCISampleDlg, CDialog)
	//{{AFX_MSG_MAP(CMCISampleDlg)
	ON_WM_SYSCOMMAND()
	ON_WM_PAINT()
	ON_WM_QUERYDRAGICON()
	ON_BN_CLICKED(IDC_PLAY, OnPlay)
	ON_BN_CLICKED(IDC_STOP, OnStop)
	ON_CBN_SELCHANGE(IDC_TRACKSELECT, OnSelchangeTrackselect)
	ON_WM_CLOSE()
	ON_BN_CLICKED(IDC_PAUSE, OnPause)
	ON_BN_CLICKED(IDC_EJECT, OnEject)	
	//}}AFX_MSG_MAP
	ON_WM_DEVICECHANGE()
	ON_MESSAGE(MM_MCINOTIFY, OnMciNotify)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CMCISampleDlg message handlers

BOOL CMCISampleDlg::OnInitDialog()
{
	CDialog::OnInitDialog();

	// Add "About..." menu item to system menu.

	// IDM_ABOUTBOX must be in the system command range.
	ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
	ASSERT(IDM_ABOUTBOX < 0xF000);

	CMenu* pSysMenu = GetSystemMenu(FALSE);
	CString strAboutMenu;
	strAboutMenu.LoadString(IDS_ABOUTBOX);
	if (!strAboutMenu.IsEmpty())
	{
		pSysMenu->AppendMenu(MF_SEPARATOR);
		pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
	}

	// Set the icon for this dialog.  The framework does this automatically
	//  when the application's main window is not a dialog
	SetIcon(m_hIcon, TRUE);			// Set big icon
	SetIcon(m_hIcon, FALSE);		// Set small icon

	

	//使停止/暂停按钮不可用
	m_btnStop.EnableWindow(FALSE);
	m_btnPause.EnableWindow(FALSE);
	
	//打开CD音频设备
	if (m_CdAudio.Open()) {		
		m_wndStatus.SetWindowText(_T("Device not ready!"));				
		m_btnPlay.EnableWindow(FALSE);
		m_btnEject.EnableWindow(FALSE);
	}
	else {
		// 为异步操作设置回调窗口
		m_CdAudio.SetCallbackWnd(this);
		m_wndStatus.SetWindowText(_T("CD播放器准备"));
	}
	
	if (!m_CdAudio.IsReady()) {
		m_btnPlay.EnableWindow(FALSE);
	}

	//为CD音频设置时间格式
	m_CdAudio.SetTimeFormat(CCdAudio::FormatTMSF);

	//更新对话框控件
	UpdateControls();

	return TRUE;  
}

void CMCISampleDlg::OnSysCommand(UINT nID, LPARAM lParam)
{
		CDialog::OnSysCommand(nID, lParam);
}


void CMCISampleDlg::OnPaint() 
{
	if (IsIconic())
	{
		CPaintDC dc(this); // device context for painting

		SendMessage(WM_ICONERASEBKGND, (WPARAM) dc.GetSafeHdc(), 0);

		// Center icon in client rectangle
		int cxIcon = GetSystemMetrics(SM_CXICON);
		int cyIcon = GetSystemMetrics(SM_CYICON);
		CRect rect;
		GetClientRect(&rect);
		int x = (rect.Width() - cxIcon + 1) / 2;
		int y = (rect.Height() - cyIcon + 1) / 2;

		// Draw the icon
		dc.DrawIcon(x, y, m_hIcon);
	}
	else
	{
		CDialog::OnPaint();
	}
}

// The system calls this to obtain the cursor to display while the user drags
//  the minimized window.
HCURSOR CMCISampleDlg::OnQueryDragIcon()
{
	return (HCURSOR) m_hIcon;
}

//播放CD音频
void CMCISampleDlg::OnPlay() 
{
	UpdateData();
	//把曲目转化为数字
	m_nTrackToPlay = 
		(m_strTrack.GetAt(0)-'0')*10 + 
		(m_strTrack.GetAt(1)-'0');

	//取得曲目长度
	CMsf msf = m_CdAudio.GetTrackLength(m_nTrackToPlay);
	
	m_tmsfFrom = CTmsf(m_nTrackToPlay, 0, 0, 0);
	m_tmsfTo = CTmsf(m_nTrackToPlay, 
		msf.GetMinute(), msf.GetSecond(), msf.GetFrame());
		
	// 播放选中的曲目
	if (!m_CdAudio.Play(m_tmsfFrom, m_tmsfTo)) {
		m_wndStatus.SetWindowText(_T("正在播放...."));		
		m_btnStop.EnableWindow();
		m_btnPause.EnableWindow();
	}

}

//停止播放
void CMCISampleDlg::OnStop() 
{
	if (!m_CdAudio.Stop()) {
		m_wndStatus.SetWindowText(_T("Stopped"));
		m_btnStop.EnableWindow(FALSE);
		m_btnPause.EnableWindow(FALSE);
		m_btnPause.SetWindowText(_T("&Pause"));
	}
}

void CMCISampleDlg::OnSelchangeTrackselect() 
{
	UpdateData();	
	m_nTrackToPlay = 
		(m_strTrack.GetAt(0)-'0')*10 + 
		(m_strTrack.GetAt(1)-'0');
	// Seek to the selected track
	if (m_nTrackToPlay > 0)
		m_CdAudio.Seek(CTmsf(m_nTrackToPlay, 0, 0, 0));
}

//关闭
void CMCISampleDlg::OnClose() 
{
	
	//停止并关闭CD音频
	if (m_CdAudio.IsReady()) {
		m_CdAudio.Stop();	
		m_CdAudio.Close();
	}
	
	CDialog::OnClose();
}

void CMCISampleDlg::OnPause() 
{
	if (m_CdAudio.GetMode() == CCdAudio::ModePlay) {
		//暂停播放
		if (!m_CdAudio.Pause()) {
			m_wndStatus.SetWindowText(_T("Paused"));
			m_btnPause.SetWindowText(_T("&Resume"));
		}	
	}
	else {
		//从当前位置重新恢复播放
		if (!m_CdAudio.Play(m_CdAudio.GetCurrentPos(), m_tmsfTo))
			m_btnPause.SetWindowText(_T("&Pause"));
			m_wndStatus.SetWindowText(_T("Playing..."));				
	}
}

void CMCISampleDlg::OnEject() 
{
	// 打开/关闭CD光驱
	m_CdAudio.OpenDoor(m_CdAudio.IsReady());
	m_btnPause.SetWindowText(_T("&Pause"));
	BOOL bReady = m_CdAudio.IsReady();
	EnableControls(bReady, bReady);
}

// 当新CD插入时执行的函数
BOOL CMCISampleDlg::OnDeviceChange( UINT nEventType, DWORD dwData ) {
	DEV_BROADCAST_HDR *pdbch = (DEV_BROADCAST_HDR *) dwData;

	switch(nEventType) {
	case DBT_DEVICEARRIVAL:						// CD drawer was closed
		if (pdbch->dbch_devicetype == DBT_DEVTYP_VOLUME) {
			PDEV_BROADCAST_VOLUME pdbcv = 
				(PDEV_BROADCAST_VOLUME) dwData;
			if (pdbcv->dbcv_flags == DBTF_MEDIA)
			{
				TCHAR szDrive[4];
				// pdbcv->unitmask contains the drive bits
				for (UINT i=0; !(pdbcv->dbcv_unitmask & (1<<i)); i++);
				wsprintf(szDrive, _T("%c:\\"), 'A'+i);		
				if (GetDriveType(szDrive) == DRIVE_CDROM) {					
					UpdateControls();					
				}
			}
			else {
			//处理网络驱动器
			}
			break;
		}
	case DBT_DEVICEREMOVECOMPLETE:
		EnableControls(FALSE, FALSE);
	break;
	}

	return TRUE;
}

void CMCISampleDlg::EnableControls(BOOL bEnablePlay, 
								   BOOL bEnableStop /* =TRUE*/) 
{
	m_comboTrack.EnableWindow(bEnablePlay);	
	m_btnPlay.EnableWindow(bEnablePlay);
	m_btnStop.EnableWindow(bEnableStop);
	m_btnPause.EnableWindow(bEnableStop);
}

// 对话框控件更新
void CMCISampleDlg::UpdateControls() {
	//取得CD上可播放曲目的序号
	DWORD n = m_CdAudio.GetNumberOfTracks();

	m_comboTrack.ResetContent();
	CString s;
	CMsf msf;
	for (UINT i=1; i<=n; i++) {
		msf = m_CdAudio.GetTrackLength(i);
		if (m_CdAudio.GetTrackType(i) == CCdAudio::TrackTypeAudio) {
			s.Format(_T("%02d    (%02d\':%02d\")"), i, 
				msf.GetMinute(), msf.GetSecond());
			m_comboTrack.AddString(s);
		}

	}
	//选择第一个曲目
	m_comboTrack.SetCurSel(0);
	
	BOOL bCanPlay = m_comboTrack.GetCount() != 0;
	
	EnableControls(bCanPlay, FALSE);
	UpdateData();	
}

LONG CMCISampleDlg::OnMciNotify(UINT wFlags, LONG lDevId) {	
	switch(wFlags) {
	case MCI_NOTIFY_SUCCESSFUL:
		m_wndStatus.SetWindowText(_T("Playback completed"));
		break;
	case MCI_NOTIFY_FAILURE:
		m_wndStatus.SetWindowText(_T("Playback interrupted!"));
		break;
	case MCI_NOTIFY_SUPERSEDED:
		m_wndStatus.SetWindowText(_T("Playback stopped!"));
		break;
	}	
	return 0L;
}