WinCE系统音量的设置.doc

WinCE系统音量的设置/=/TITLE:/ WinCE系统音量的设置/AUTHOR:/ norains/DATE:/ Sunday 8-April-2007/Environment:/ EVC4.0 + Standard SDK 4.2/ EVC4.0 + Standard SDK 5.0/= 首先我们来看一段最简单的改变音量的代码: DWORD dwVolume = 0xAAAAAAAA; waveOutSetVolume(0,dwVolume); waveOutSetVolume()的第一个参数是设备ID,因为需要更改的是整个系统音量,所以在这里直接取0值即可;第二个参数是需要设置的音量数值,范围是从 0x0 0xFFFFFFFF. 但这个函数的功能却也是非常有限的,也就是说,它只能更改系统的主音量;如果想修改屏幕点击声,则就无能为力. 有些细心的朋友会从控制面板的声音入手,发现每次在控制面板调节声音,相应的ControlPanelVolume下的键值数值都会变更.但如果是直接修其下的改注册表,却是无论如何都达不到相应的功能的-因为没有通知系统,注册表已经被修改. 如果需要告知系统,注册表已经修改,并请系统依照修改的数值来更改音量,则需要调用微软一个未公开的函数:AudioUpdateFromRegistry(). 这个函数在文档中是无法搜索到,如果需要调用这个函数,可以有两种方法. 一是直接包含pwinuser.h文件,然后直接调用. 二是调用coredll.dll库,引出该函数并使用. 这里展示一个调用的例子: typedef void (WINAPI *DLL_AUDIOUPDATEFROMREGISTRY)(); DLL_AUDIOUPDATEFROMREGISTRY Dll_AudioUpdateFromRegistry = NULL; HINSTANCE hCoreDll = LoadLibrary(TEXT(coredll.dll); if (hCoreDll) . Dll_AudioUpdateFromRegistry = (DLL_AUDIOUPDATEFROMREGISTRY)GetProcAddress(hCoreDll, _T(AudioUpdateFromRegistry); if (Dll_AudioUpdateFromRegistry) . (Dll_AudioUpdateFromRegistry)(); 只要更新了注册表,然后调用该函数,则系统会根据键值来进行相应的调整. 那么现在让我们来看看位于ControlPanelVolume注册表中各键值的意义: Volume: 系统的主音量,范围是0x0 0xFFFFFFFF. Screen: 屏幕敲击声. 当数值为0时即为无声,1为柔和,65538为洪亮 Key: 键盘敲击声,数值的意义和Screen相同. Mute: 控制其它静音的选项. 置0x04位为1时允许事件声音,0x02允许应用程序声音,0x01允许警告声.需要注意的是,如果不允许应用程序声音,则警告声位也将被忽略. 如果每次更改音量都要改写注册表,调用动态链接库,会显得比较麻烦.为了写代码的便利,在此封装了这个声音的操作:(注:CReg 请参见此篇文章:/norains/archive/2007/04/08/1556296.aspx) /*/ SysVolume.h: interface for the CSysVolume class./Version:/ 1.0.0/Date:/ 2007.04.08/*/#ifndef SYSVOLUME_H#define SYSVOLUME_H#include Reg.h/-/Macro define#define MIN_VOLUME 0#define MAX_VOLUME 0xFFFFFFFF/-/Enum valueenum VolumeModeType. VOL_SOFT, VOL_LOUD, VOL_MUTE;/-class CSysVolume .public: BOOL SetVolumeScreenTap(VolumeModeType volMode); BOOL SetVolumeKeyClick(VolumeModeType volMode); BOOL EnableSoundNotification(BOOL bEnable); BOOL EnableSoundApplication(BOOL bEnable); BOOL EnableSoundEvent(BOOL bEnable); BOOL SetVolume(DWORD dwVol); CSysVolume(); virtual CSysVolume();protected: BOOL Apply(); CReg m_Reg;#endif /#ifndef SYSVOLUME_H /*/ / SysVolume.cpp: implementation of the CSysVolume class./*/#include stdafx.h#include SysVolume.h/=/Macro define/Registry KEY#define BASE_KEY HKEY_CURRENT_USER#define SUB_KEY TEXT(ControlPanelVolume)#define VALUE_VOLUME TEXT(Volume)#define VALUE_SCREEN TEXT(Screen)#define VALUE_KEY TEXT(key)#define VALUE_MUTE TEXT(Mute)/For the screen tap and the key click#define VOL_VALUE_MUTE 0#define VOL_VALUE_LOUD 65538#define VOL_VALUE_SOFT 1/The bit for sound#define BIT_EVENT 0x4#define BIT_APPLICATION 0x2#define BIT_NOTIFICATION 0x1/=/*/ Construction/Destruction/*/CSysVolume:CSysVolume(). m_Reg.Create(BASE_KEY, SUB_KEY);CSysVolume:CSysVolume()./-/Description:/ Apply the volume/-BOOL CSysVolume:Apply(). typedef void (WINAPI *DLL_AUDIOUPDATEFROMREGISTRY)(); DLL_AUDIOUPDATEFROMREGISTRY Dll_AudioUpdateFromRegistry = NULL; HINSTANCE hCoreDll = LoadLibrary(TEXT(coredll.dll); if (hCoreDll) . Dll_AudioUpdateFromRegistry = (DLL_AUDIOUPDATEFROMREGISTRY)GetProcAddress(hCoreDll, _T(AudioUpdateFromRegistry); if (Dll_AudioUpdateFromRegistry) . (Dll_AudioUpdateFromRegistry)(); else . return FALSE; FreeLibrary(hCoreDll); else . return FALSE; return TRUE;/-/Description:/ Enable the sound for events/-BOOL CSysVolume:EnableSoundEvent(BOOL bEnable). if(m_Reg.IsOK() != TRUE) . return FALSE; DWORD dwVal = m_Reg.GetValueDW(VALUE_MUTE); if(bEnable = TRUE) . dwVal |= BIT_EVENT; else . dwVal &= BIT_EVENT; m_Reg.SetDW(VALUE_MUTE,dwVal); return Apply();/-/Description:/ Enable the sound for application/-BOOL CSysVolume:EnableSoundApplication(BOOL bEnable). if(m_Reg.IsOK() != TRUE) . return FALSE; DWORD dwVal = m_Reg.GetValueDW(VALUE_MUTE); if(bEnable = TRUE) . dwVal |= BIT_APPLICATION; else . dwVal &= BIT_APPLICATION; m_Reg.SetDW(VALUE_MUTE,dwVal); return Apply();/-/Description:/ Enable the sound for notifications. If the sound of application is/mute, the sound of notification is mute too./-BOOL CSysVolume:EnableSoundNotification(BOOL bEnable). if(m_Reg.IsOK() != TRUE) . return FALSE; DWORD dwVal = m_Reg.GetValueDW(VALUE_MUTE); if(bEnable = TRUE) . dwVal |= BIT_NOTIFICATION; else . dwVal &= BIT_NOTIFICATION; m_Reg.SetDW(VALUE_MUTE,dwVal); return Apply();/-/Description:/ Set the key click volume/-BOOL CSysVolume:SetVolumeKeyClick(VolumeModeType volMode). DWORD dwVol = 0; switch(volMode) . case VOL_SOFT: dwVol = VOL_VALUE_SOFT; break; case VOL_LOUD: dwVol = VOL_VALUE_LOUD; break; case VOL_MUTE: dwVol = VOL_VALUE_MUTE; break; if(m_Reg.IsOK() != TRUE) . return FALSE; m_Reg.SetDW(VALUE_KEY,dwVol); return Apply();/-/Description:/ Set the screen tap volume/-BOOL CSysVolume:SetVolumeScreenTap(VolumeModeType volMode). DWORD dwVol = 0; switch(volMode) . case VOL_SOFT: dwVol = VOL_VALUE_SOFT; break; case VOL_LOUD: dwVol = VOL_VALUE_LOUD; break; case VOL_MUTE: dwVol = VOL_VALUE_MUTE; break; if(m_Reg.IsOK() != TRUE) . return FALSE; m_Reg.SetDW(VALUE_SCREEN,dwVol); return Apply();/-/Description:/ Set the volume. /Parameters:/ dwVol: The volume to set. And the r