Does anyone know how to change or control the system's volume with code? Withou having to open the volume control window, i'd like to raise or lower thevolume of the system, or even better of each individual device (CD Audio, Wav, MIDI etc..)
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Does anyone know how to change or control the system's volume with code? Withou having to open the volume control window, i'd like to raise or lower thevolume of the system, or even better of each individual device (CD Audio, Wav, MIDI etc..)
It took me a long time to get this, but here it is for you. It's probably a little confusing, so if you have any problems, email me. First put the stuff in the module and form and mess with it. You should catch on to it.
Good luck
bob
[email protected]
Put this in a module. Where it says Public Const MIXERLINE_COMPONENTTYPE_SRC_something =(MIXERLINE_COMPONENTTYPE_SRC_FIRST + a number) feel free to put in whatever you want to make it work. you'll have to fiddle with them to get the particular things you want changed to change.
Option Explicit
Public hmem As Long
Public Const MMSYSERR_NOERROR = 0
Public Const MAXPNAMELEN = 32
Public Const MIXER_LONG_NAME_CHARS = 64
Public Const MIXER_SHORT_NAME_CHARS = 16
Public Const MIXER_GETLINEINFOF_COMPONENTTYPE = &H3&
Public Const MIXER_GETCONTROLDETAILSF_VALUE = &H0&
Public Const MIXER_SETCONTROLDETAILSF_VALUE = &H0&
Public Const MIXER_GETLINECONTROLSF_ONEBYTYPE = &H2&
Public Const MIXERLINE_COMPONENTTYPE_DST_FIRST = &H0&
Public Const MIXERLINE_COMPONENTTYPE_SRC_FIRST = &H1000&
Public Const MIXERLINE_COMPONENTTYPE_DST_SPEAKERS = _
(MIXERLINE_COMPONENTTYPE_DST_FIRST + 4)
Public Const MIXERLINE_COMPONENTTYPE_SRC_MICROPHONE = _
(MIXERLINE_COMPONENTTYPE_SRC_FIRST + 3)
Public Const MIXERLINE_COMPONENTTYPE_SRC_LINE = _
(MIXERLINE_COMPONENTTYPE_SRC_FIRST + 2)
Public Const MIXERLINE_COMPONENTTYPE_SRC_CD = _
(MIXERLINE_COMPONENTTYPE_SRC_FIRST + 5)
Public Const MIXERLINE_COMPONENTTYPE_SRC_PC = _
(MIXERLINE_COMPONENTTYPE_SRC_FIRST + 10)
Public Const MIXERCONTROL_CT_CLASS_FADER = &H50000000
Public Const MIXERCONTROL_CT_UNITS_UNSIGNED = &H30000
Public Const MIXERCONTROL_CONTROLTYPE_FADER = _
(MIXERCONTROL_CT_CLASS_FADER Or _
MIXERCONTROL_CT_UNITS_UNSIGNED)
Public Const MIXERCONTROL_CONTROLTYPE_VOLUME = _
(MIXERCONTROL_CONTROLTYPE_FADER + 1)
Public Type MIXERCONTROLDETAILS
cbStruct As Long
dwControlID As Long
cChannels As Long
item As Long
cbDetails As Long
paDetails As Long
End Type
Public Type MIXERCONTROLDETAILS_UNSIGNED
dwValue As Long
End Type
Public Type MIXERCONTROL
cbStruct As Long
dwControlID As Long
dwControlType As Long
fdwControl As Long
cMultipleItems As Long
szShortName As String * MIXER_SHORT_NAME_CHARS
szName As String * MIXER_LONG_NAME_CHARS
lMinimum As Long
lMaximum As Long
reserved(10) As Long
End Type
Public Type MIXERLINECONTROLS
cbStruct As Long
dwLineID As Long
dwControl As Long
cControls As Long
cbmxctrl As Long
pamxctrl As Long
End Type
Public Type MIXERLINE
cbStruct As Long
dwDestination As Long
dwSource As Long
dwLineID As Long
fdwLine As Long
dwUser As Long
dwComponentType As Long
cChannels As Long
cConnections As Long
cControls As Long
szShortName As String * MIXER_SHORT_NAME_CHARS
szName As String * MIXER_LONG_NAME_CHARS
dwType As Long
dwDeviceID As Long
wMid As Integer
wPid As Integer
vDriverVersion As Long
szPname As String * MAXPNAMELEN
End Type
Declare Function GlobalAlloc Lib "kernel32" (ByVal wFlags As Long, _
ByVal dwBytes As Long) As Long
Declare Function GlobalLock Lib "kernel32" (ByVal hmem As Long) As Long
Declare Function GlobalFree Lib "kernel32" (ByVal hmem As Long) As Long
Declare Sub CopyPtrFromStruct Lib "kernel32" Alias "RtlMoveMemory" _
(ByVal ptr As Long, struct As Any, ByVal cb As Long)
Declare Sub CopyStructFromPtr Lib "kernel32" Alias "RtlMoveMemory" _
(struct As Any, ByVal ptr As Long, ByVal cb As Long)
Declare Function mixerOpen Lib "winmm.dll" _
(phmx As Long, ByVal uMxId As Long, ByVal dwCallback As Long, _
ByVal dwInstance As Long, ByVal fdwOpen As Long) As Long
Declare Function mixerSetControlDetails Lib "winmm.dll" _
(ByVal hmxobj As Long, pmxcd As MIXERCONTROLDETAILS, _
ByVal fdwDetails As Long) As Long
Declare Function mixerGetLineInfo Lib "winmm.dll" _
Alias "mixerGetLineInfoA" (ByVal hmxobj As Long, _
pmxl As MIXERLINE, ByVal fdwInfo As Long) As Long
Declare Function mixerGetLineControls Lib "winmm.dll" _
Alias "mixerGetLineControlsA" (ByVal hmxobj As Long, _
pmxlc As MIXERLINECONTROLS, ByVal fdwControls As Long) As Long
Public lFlags As Long
Public lDeviceID As Long
Public Declare Function mciSendCommand Lib "winmm.dll" _
Alias "mciSendCommandA" (ByVal wDeviceID As Long, _
ByVal uMessage As Long, ByVal dwParam1 As Long, _
ByRef dwParam2 As Any) As Long
Public Declare Function mciGetErrorString Lib "winmm.dll" _
Alias "mciGetErrorStringA" (ByVal dwError As Long, _
ByVal lpstrBuffer As String, _
ByVal uLength As Long) As Long
Public Function fGetVolumeControl(ByVal hmixer As Long, _
ByVal componentType As Long, ByVal ctrlType As Long, _
ByRef mxc As MIXERCONTROL) As Boolean
Dim mxlc As MIXERLINECONTROLS
Dim mxl As MIXERLINE
Dim hmem As Long
Dim rc As Long
mxl.cbStruct = Len(mxl)
mxl.dwComponentType = componentType
rc = mixerGetLineInfo(hmixer, mxl, MIXER_GETLINEINFOF_COMPONENTTYPE)
If MMSYSERR_NOERROR = rc Then
With mxlc
.cbStruct = Len(mxlc)
.dwLineID = mxl.dwLineID
.dwControl = ctrlType
.cControls = 1
.cbmxctrl = Len(mxc)
End With
hmem = GlobalAlloc(&H40, Len(mxc))
mxlc.pamxctrl = GlobalLock(hmem)
mxc.cbStruct = Len(mxc)
rc = mixerGetLineControls(hmixer, mxlc, MIXER_GETLINECONTROLSF_ONEBYTYPE)
If MMSYSERR_NOERROR = rc Then
fGetVolumeControl = True
Call CopyStructFromPtr(mxc, mxlc.pamxctrl, Len(mxc))
Else
fGetVolumeControl = False
End If
Call GlobalFree(hmem)
Exit Function
End If
fGetVolumeControl = False
End Function
Put this in the form code with 5 scroll bars; one for main volume, mic, line, pc, and CD.
Option Explicit
Dim hmixer As Long
Dim volCtrl As MIXERCONTROL
Private Function fSetVolumeControl(ByVal hmixer As Long, _
mxc As MIXERCONTROL, ByVal volume As Long) As Boolean
Dim rc As Long
Dim mxcd As MIXERCONTROLDETAILS
Dim vol As MIXERCONTROLDETAILS_UNSIGNED
With mxcd
.item = 0
.dwControlID = mxc.dwControlID
.cbStruct = Len(mxcd)
.cbDetails = Len(vol)
End With
hmem = GlobalAlloc(&H40, Len(vol))
mxcd.paDetails = GlobalLock(hmem)
mxcd.cChannels = 1
vol.dwValue = volume
Call CopyPtrFromStruct(mxcd.paDetails, vol, Len(vol))
rc = mixerSetControlDetails(hmixer, mxcd, MIXER_SETCONTROLDETAILSF_VALUE)
Call GlobalFree(hmem)
If MMSYSERR_NOERROR = rc Then
fSetVolumeControl = True
Else
fSetVolumeControl = False
End If
End Function
Private Sub vScroll1_Change()
Dim lVol As Long
Dim bOK As Integer
bOK = fGetVolumeControl(hmixer, _
MIXERLINE_COMPONENTTYPE_DST_SPEAKERS, _
MIXERCONTROL_CONTROLTYPE_VOLUME, volCtrl)
lVol = CLng(VScroll1.Value) * 2
Call fSetVolumeControl(hmixer, volCtrl, lVol)
End Sub
Private Sub vScroll1_Scroll()
Dim lVol As Long
Dim bOK As Integer
bOK = fGetVolumeControl(hmixer, _
MIXERLINE_COMPONENTTYPE_DST_SPEAKERS, _
MIXERCONTROL_CONTROLTYPE_VOLUME, volCtrl)
lVol = CLng(VScroll1.Value) * 2
Call fSetVolumeControl(hmixer, volCtrl, lVol)
End Sub
Private Sub vScroll2_Change()
Dim lVol As Long
Dim bOK As Integer
bOK = fGetVolumeControl(hmixer, _
MIXERLINE_COMPONENTTYPE_SRC_MICROPHONE, _