[求助]媒体播放时怎样控制音量

我爱彩虹

小弟最近在用CB做播放器，基本功能都实现了，就是不能控制音量，还有就是播放窗口不能变大和变小，请高手帮忙看看该怎么办？

ilikenba

在Timer的OnTimer事件中添加代码，要将Enabled属性设成true，才开始执行！

ilikenba

你是将Form2的类包含进去了，应该没有问题！

我爱彩虹

<>我定义了两个窗体:Form1和Form2, 保存为:Unit1.h和Unit2.h,其中Form1是主窗体,Form2是副窗体,我想实现的功能是Form1能够调用Form2,于是我在Form1中添加了Unit2.h,这种样子:</P><>#include &lt;vcl.h&gt;
#pragma hdrstop
#include "SoundControl.h"
$ S( @* B0 y$ c8 E' f#include "Unit1.h"//主窗体
, l* W* u" ^& W; [#include "Unit2.h"//复窗体</P><>结果运行的时候就要报下面的错误:</P><>[Linker Error] Unresolved external '_playForm' referenced from C:\PROGRAM FILES\BORLAND\CBUILDER6\PROJECTS\主窗口\UNIT1.OBJ</P><>各位大虾,我该怎么修改才能调用Form2啊?</P>[em06]

我爱彩虹

怎么在时间控件里添加代码啊？

ilikenba

<>可以！</P>

小菜菜同学

是不是可以加个时间控件呀，用<b><FONT color=#000066>播放开关控制？</FONT></b>

我爱彩虹

<FONT color=#000066><b>ilikenba大哥，</b><FONT color=#000000>[em01]</FONT><b>在麻烦你哈，我要是想在播放的时候把播放的视频或音频文件的时显示出来，我该怎么办啊？？这几天为了这个我头都搞大了.</b></FONT>

ilikenba

<DIV class=HtmlCode>
; v' Y3 X( ]  ?) l' Q3 r& o( s<>//---------------------------------------------------------------------------</P>
<>#ifndef SoundControlH
#define SoundControlH
//---------------------------------------------------------------------------
9 }5 J, A7 l) E" j% q#include &lt;Classes.hpp&gt;
% s% I; b$ W  p#include &lt;mmsystem.h&gt;
#include &lt;mmreg.h&gt;</P>
<>
2 K; B: C  i- H  ?bool GetVolumeControl(HMIXER hmixer ,long componentType,long ctrlType,MIXERCONTROL* mxc);</P>
5 f8 p7 u7 f" B8 ]7 P% V<>long GetMuteValue(HMIXER hmixer ,MIXERCONTROL *mxc) ;
! b1 Y- W) O" m. n. H/ w: s  Vunsigned GetVolumeValue(HMIXER hmixer ,MIXERCONTROL *mxc);
bool SetVolumeValue(HMIXER hmixer ,MIXERCONTROL *mxc, long volume);
% m* X) T+ |, P% ^# M/ p, _/ ~5 v" Cbool SetMuteValue(HMIXER hmixer ,MIXERCONTROL *mxc, bool mute);</P>
# S" g) r' @& c0 m; j<>
//下面四个是输出函数，可以自己调用
bool WINAPI SetVolume(long dev,long vol);//设置设备的音量
( V! z0 `* x  W/ S9 @+ A" _2 Lunsigned WINAPI GetVolume(int dev);//得到设备的音量dev=0主音量，1WAVE ,2MIDI ,3 LINE IN</P>
<>bool WINAPI SetMute(long dev,bool vol);//设置设备静音
$ A2 v- y/ n$ Fbool WINAPI GetMute(long dev);
#endif</P>
# @& B: |% J) L: H. r
( u: e. N. r( c  F$ _' D<>bool GetVolumeControl(HMIXER hmixer ,long componentType,long ctrlType,MIXERCONTROL* mxc)
{
7 G3 D) e) O# u" d$ n. MMIXERLINECONTROLS mxlc;
MIXERLINE mxl;
' t/ x) Q, T: a' D; nmxl.cbStruct = sizeof(mxl);
mxl.dwComponentType = componentType;
if(!mixerGetLineInfo((HMIXEROBJ)hmixer, &amp;mxl, MIXER_GETLINEINFOF_COMPONENTTYPE))
* G) h( b  w% h- P$ E2 H$ j{
mxlc.cbStruct = sizeof(mxlc);
0 k9 {" H. n; Q" G  z- X) w! q! E# nmxlc.dwLineID = mxl.dwLineID;
# _5 ], ]6 r2 X1 mmxlc.dwControlType = ctrlType;
  t& i$ N% M! A- ]5 Q' B& \mxlc.cControls = 1;
4 `3 K* g3 h- t8 C- U; |7 z+ S! o8 Qmxlc.cbmxctrl = sizeof(MIXERCONTROL);
9 h0 o" X3 J7 K3 g5 e. Y2 w$ l  ]' Imxlc.pamxctrl = mxc;
if(mixerGetLineControls((HMIXEROBJ)hmixer,&amp;mxlc,MIXER_GETLINECONTROLSF_ONEBYTYPE))
return 0;
7 ?& i- y- S, ?3 w- v$ Delse
) F$ Y5 U0 P+ Nreturn 1;
}
return 0;
3 r7 O# c7 ~; R, a}
8 i0 q6 P4 ~. t. p% h9 a* G//---------------------------------------------------------------------------
7 ^4 q7 W9 t! Jlong GetMuteValue(HMIXER hmixer ,MIXERCONTROL *mxc)
{
MIXERCONTROLDETAILS mxcd;
MIXERCONTROLDETAILS_BOOLEAN mxcdMute;
mxcd.hwndOwner = 0;
mxcd.cbStruct = sizeof(mxcd);
8 {; G. T" y9 v+ B  O% R' Mmxcd.dwControlID = mxc-&gt;dwControlID;
$ x; B3 I' F  Bmxcd.cbDetails = sizeof(mxcdMute);
mxcd.paDetails = &amp;mxcdMute;
' x: w: [5 F5 H2 u; Pmxcd.cChannels = 1;
% e' J" R+ D$ Fmxcd.cMultipleItems = 0;
if (mixerGetControlDetails((HMIXEROBJ)hmixer, &amp;mxcd,MIXER_OBJECTF_HMIXER|MIXER_GETCONTROLDETAILSF_VALUE))
return -1;
return mxcdMute.fValue;
} </P>
<>//---------------------------------------------------------------------------
- c: z- ?- X4 d3 x# T( gunsigned GetVolumeValue(HMIXER hmixer ,MIXERCONTROL *mxc)
2 T  @% o% C( ]{
MIXERCONTROLDETAILS mxcd;
  J0 ?9 }$ J7 c  M" \MIXERCONTROLDETAILS_UNSIGNED vol; vol.dwValue=0;
7 V  x5 q8 I0 ?4 V: l4 omxcd.hwndOwner = 0;
mxcd.cbStruct = sizeof(mxcd);
& O% x: z/ N1 q. X$ ~mxcd.dwControlID = mxc-&gt;dwControlID;
mxcd.cbDetails = sizeof(vol);
. F2 v( i: P# e* L8 hmxcd.paDetails = &amp;vol;
mxcd.cChannels = 1;
if(mixerGetControlDetails((HMIXEROBJ)hmixer, &amp;mxcd, MIXER_OBJECTF_HMIXER|MIXER_GETCONTROLDETAILSF_VALUE))
return -1;
return vol.dwValue;
} </P>
4 |' @! v1 c3 H- X0 U4 Y<>//---------------------------------------------------------------------------
5 w# W' L- r& O* Wbool SetMuteValue(HMIXER hmixer ,MIXERCONTROL *mxc, bool mute)
9 P* U  p3 T4 N& E5 W$ O7 k( Y{
2 d/ b+ L2 e7 W, qMIXERCONTROLDETAILS mxcd;
, c7 V) z+ K/ n; U7 L9 }$ IMIXERCONTROLDETAILS_BOOLEAN mxcdMute;mxcdMute.fValue=mute;
mxcd.hwndOwner = 0;
mxcd.dwControlID = mxc-&gt;dwControlID;
0 v7 J2 F7 R0 Y) \! B" X' omxcd.cbStruct = sizeof(mxcd);
mxcd.cbDetails = sizeof(mxcdMute);
mxcd.paDetails = &amp;mxcdMute;
mxcd.cChannels = 1;
mxcd.cMultipleItems = 0;
if (mixerSetControlDetails((HMIXEROBJ)hmixer, &amp;mxcd, MIXER_OBJECTF_HMIXER|MIXER_SETCONTROLDETAILSF_VALUE))
return 0;
' E4 d  D4 y* W) N$ o- }/ U2 mreturn 1;
5 s% H4 {: x* L  d3 W} </P>
: H* Q0 e, G- c# z3 T7 U<>//---------------------------------------------------------------------------</P>
<>bool SetVolumeValue(HMIXER hmixer ,MIXERCONTROL *mxc, long volume)
{
MIXERCONTROLDETAILS mxcd;
9 d, Z. Q3 O8 w% C. |! fMIXERCONTROLDETAILS_UNSIGNED vol;vol.dwValue = volume;
mxcd.hwndOwner = 0;
mxcd.dwControlID = mxc-&gt;dwControlID;
5 {+ @2 H7 a" omxcd.cbStruct = sizeof(mxcd);
- ~; X( Q9 i" ymxcd.cbDetails = sizeof(vol);
: Q5 a! ~) k3 qmxcd.paDetails = &amp;vol;
4 i3 T9 H8 L$ N  [# v5 rmxcd.cChannels = 1;
if(mixerSetControlDetails((HMIXEROBJ)hmixer, &amp;mxcd, MIXER_OBJECTF_HMIXER|MIXER_SETCONTROLDETAILSF_VALUE))
6 c7 @" U/ O9 A8 treturn 0;
return 1;
} </P>
<>
//---------------------------------------------------------------------------
unsigned WINAPI GetVolume(int dev)//得到设备的音量dev=0主音量，1WAVE ,2MIDI ,3 LINE IN
{</P>
<>long device;unsigned rt=0;
8 L  J9 I! S1 qMIXERCONTROL volCtrl;
  S' D8 X6 t# m' a) ^& X& _% ^7 {HMIXER hmixer;
: M" H8 B! v7 s0 Sswitch (dev)
3 O; B1 M# @' y: }{
case 1:
( m' j9 x; W5 f+ Qdevice=MIXERLINE_COMPONENTTYPE_SRC_WAVEOUT; break;
8 j* b( X2 E" N8 Tcase 2:
device=MIXERLINE_COMPONENTTYPE_SRC_SYNTHESIZER; break;
$ k4 F9 E: G. l% I, v- r4 Hcase 3:
// device=MIXERLINE_COMPONENTTYPE_SRC_COMPACTDISC; break; // cd 音量
1 [% h; o" i3 q. z// device=MIXERLINE_COMPONENTTYPE_SRC_MICROPHONE; break; //麦克风音量
// device=MIXERLINE_COMPONENTTYPE_SRC_LINE; break; //PC 扬声器音量
device=MIXERLINE_COMPONENTTYPE_SRC_COMPACTDISC; break; </P>
<>default:
) m) L8 I0 c8 \& Y% }: z9 V/ |) Vdevice=MIXERLINE_COMPONENTTYPE_DST_SPEAKERS;
! X' h8 P3 |  ]! f8 e: \}</P>
<>if(mixerOpen(&amp;hmixer, 0, 0, 0, 0)) return 0;
if(!GetVolumeControl(hmixer,device,MIXERCONTROL_CONTROLTYPE_VOLUME,&amp;volCtrl))
: l& G  B0 o* e/ f0 U1 F7 T$ m( t$ sreturn 0;
rt=GetVolumeValue(hmixer,&amp;volCtrl)*100/volCtrl.Bounds.lMaximum;
8 G$ C6 v$ X, Y' v6 omixerClose(hmixer);
- e" L2 j. O, G' ?0 }: Z4 zreturn rt;</P>
<>}</P>
* }2 z! u/ W: |<>//---------------------------------------------------------------------------</P>
1 F8 U: e/ q1 K+ d1 a* C<>bool WINAPI SetVolume(long dev,long vol)//设置设备的音量
( S, Q  k5 [$ J1 C4 W. x{
" c( D. i/ Q8 n. b// dev =0,1,2 分别表示主音量,波形,MIDI ,LINE IN
7 V0 j, V& n' V( P. e7 U// vol=0-100 表示音量的大小 , 设置与返回音量的值用的是百分比，即音量从0 - 100，而不是设备的绝对值
// retrun false 表示设置音量的大小的操作不成功
// retrun true 表示设置音量的大小的操作成功</P>
<>long device;
bool rc=false;
MIXERCONTROL volCtrl;
HMIXER hmixer;
switch (dev)
{
2 U2 ^- j6 |  n; Y: v, `: i- p" Wcase 1:
device=MIXERLINE_COMPONENTTYPE_SRC_WAVEOUT; break;
case 2:
device=MIXERLINE_COMPONENTTYPE_SRC_SYNTHESIZER; break;
case 3:
device=MIXERLINE_COMPONENTTYPE_SRC_COMPACTDISC; break;</P>
<>default:
device=MIXERLINE_COMPONENTTYPE_DST_SPEAKERS;
} </P>
2 E. }: H& k- o9 u9 U6 D0 z<>if(mixerOpen(&amp;hmixer, 0, 0, 0, 0)) return 0;</P>
% E) p% Y5 K8 ~9 T2 l$ N<>if(GetVolumeControl(hmixer,device,MIXERCONTROL_CONTROLTYPE_VOLUME,&amp;volCtrl))
{
vol=vol*volCtrl.Bounds.lMaximum/100;
if(SetVolumeValue(hmixer,&amp;volCtrl,vol))
2 M& P9 Z; J+ X6 `/ s. frc=true;
}
2 |' Y) Y6 q4 q$ O7 w: nmixerClose(hmixer);
7 B: ~& M6 D( M+ y9 zreturn rc;
} </P>
) q3 _4 [, V8 [# i! t<>//---------------------------------------------------------------------------</P>
( g( c0 G0 M/ I  S<>bool WINAPI SetMute(long dev,bool vol)//设置设备静音
{
// dev =0,1,2 分别表示主音量,波形,MIDI ,LINE IN
// vol=0,1 分别表示取消静音,设置静音
// retrun false 表示取消或设置静音操作不成功
% ?0 V- r! M- b+ d  z; y) p: P// retrun true 表示取消或设置静音操作成功</P>
<>long device;
& C3 b/ _- G3 P7 Q4 w% Qbool rc=false;
" s9 n; \# f- b8 @1 A$ eMIXERCONTROL volCtrl;
: V/ m; M% l. k: lHMIXER hmixer;
switch (dev)
" A/ s$ R7 l: X* F2 \7 [: W{
case 1:
/ `' i* ~5 W* ~8 s  U/ v$ W: ndevice=MIXERLINE_COMPONENTTYPE_SRC_WAVEOUT; break;
  J1 f/ s) J* y$ U/ O) e8 F' hcase 2:
+ m8 J4 }' }2 Qdevice=MIXERLINE_COMPONENTTYPE_SRC_SYNTHESIZER; break;
* }4 Y, p! A+ R1 N! p$ ^5 scase 3:
* F: a  O5 X# ?& j! u0 _device=MIXERLINE_COMPONENTTYPE_SRC_COMPACTDISC; break; </P>
2 S. b$ P0 n& D7 b$ i<>default:
( I# f4 |- R+ L- X1 Ldevice=MIXERLINE_COMPONENTTYPE_DST_SPEAKERS;
} </P>
6 ^6 ]0 U! A: Y4 _; J<>if(mixerOpen(&amp;hmixer, 0, 0, 0, 0)) return 0;
if(GetVolumeControl(hmixer,device,MIXERCONTROL_CONTROLTYPE_MUTE,&amp;volCtrl))
if(SetMuteValue(hmixer,&amp;volCtrl,(bool)vol))
* S8 J0 E- q/ h% z* }3 Rrc=true;
mixerClose(hmixer);
! _3 e0 `, ?0 v* e4 Sreturn rc;
} </P>
( D+ W( p& e' j$ M<>//---------------------------------------------------------------------------</P>
<>bool WINAPI GetMute(long dev)//检查设备是否静音
: w7 d. A' h3 k: \& h$ {; G4 Z{
7 b, s+ n$ ^  c; X+ V//dev =0,1,2 分别表示主音量，波形,MIDI ,LINE IN
4 ^6 A, `6 D2 s. m* f  b- I# w; K// retrun false 表示没有静音
  Y" e' N$ Q& Y- |// retrun true 表示静音
$ ?' j# p! L6 l" vlong device;
7 p! G4 H" ~+ u4 E/ Y& Zbool rc=false;
MIXERCONTROL volCtrl;
: O# C' m- u$ E% S. H4 T. i1 H% s  IHMIXER hmixer;
switch (dev)
# N) n) n; A* B0 s, J9 E- C{
2 S1 p% h) D  j7 x& @case 1:
device=MIXERLINE_COMPONENTTYPE_SRC_WAVEOUT; break;
4 c8 j# K3 f" ^4 ccase 2:
  N( o" A' p/ _6 N2 qdevice=MIXERLINE_COMPONENTTYPE_SRC_SYNTHESIZER; break;
case 3:
device=MIXERLINE_COMPONENTTYPE_SRC_COMPACTDISC; break;
default:
device=MIXERLINE_COMPONENTTYPE_DST_SPEAKERS;
! S/ C2 |6 L2 s' K( \2 V} </P>
. R. ]* x8 t; N<>if(mixerOpen(&amp;hmixer, 0, 0, 0, 0)) return 0; </P>
1 Z8 T4 w' D, g6 S<P>if(GetVolumeControl(hmixer,device,MIXERCONTROL_CONTROLTYPE_MUTE,&amp;volCtrl))
rc=GetMuteValue(hmixer,&amp;volCtrl);
mixerClose(hmixer);
1 {" M0 o! l) s# @2 }" Ereturn rc;</P>
1 x0 d+ Y% }6 i<P>}</P></DIV>
<P><b><EM><FONT style="BACKGROUND-COLOR: #fdfddf" face=Tahoma>上面的存为SoundControl.h</FONT></EM></b></P>
<DIV class=HtmlCode>
<P>#include &lt;vcl.h&gt;
#pragma hdrstop
#include "SoundControl.h"
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
- H$ [- s3 E2 I, a" ^/ m/ x#pragma resource "*.dfm"
TForm1 *Form1;
6 G4 r, J" }- }$ B$ X; m$ G$ p//---------------------------------------------------------------------------
$ i" U& u) Y3 l2 S( E1 c__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{</P>
<P>}</P>
<P>void __fastcall TForm1::CheckBox1Click(TObject *Sender)
" q7 u( h4 Z2 l( q4 n, }{
SetMute(0,CheckBox1-&gt;Checked);
2 w4 L8 n. e( e2 G5 y# L}
; J! m' q% J+ L, l" s//---------------------------------------------------------------------------
, v/ s0 S& ~9 a2 ivoid __fastcall TForm1::TrackBar1Change(TObject *Sender)
% X7 r* t/ c- |  N: T* B4 P{
     SetVolume(0,TrackBar1-&gt;Position);
9 Z3 y- L( L# \, U}
- r- B& e9 J, x# Nvoid __fastcall TForm1::Button1Click(TObject *Sender)
{
* S; y9 J  N- I. U1 ^) K   TrackBar1-&gt;Position = GetVolume(1);
}
. E3 q& o' b0 i# j' d6 v, ?% Svoid __fastcall TForm1::Button3Click(TObject *Sender)
5 T& p  F/ {. p/ A1 g- p$ u{
    CheckBox1-&gt;Checked=  GetMute(0);
}</P></DIV>