请求成员______是非类型的

Question

美好的一天美妙的地球计算机人!

这是名为AudioQueue.h的文件中的结构:

typedef struct AudioQueueBuffer {
const UInt32                    mAudioDataBytesCapacity;
void * const                    mAudioData;
UInt32                          mAudioDataByteSize;
void *                          mUserData;

const UInt32                    mPacketDescriptionCapacity;
AudioStreamPacketDescription *  const mPacketDescriptions;
UInt32                          mPacketDescriptionCount;
#ifdef __cplusplus
AudioQueueBuffer() : mAudioDataBytesCapacity(0), mAudioData(0), mPacketDescriptionCapacity(0), mPacketDescriptions(0) { }
#endif
} AudioQueueBuffer;

/*!
@typedef    AudioQueueBufferRef
@abstract   An pointer to an AudioQueueBuffer.
*/
typedef AudioQueueBuffer *AudioQueueBufferRef;

然后在AudioPlayer.h的标题中有这个:

    AudioQueueBufferRef             mBuffers[kNumberBuffers];

然后我要做的是:

for (int i = 0; i < kNumberBuffers; ++i) {

    printf("%i\n", &mBuffers[i].mAudioData );

    XThrowIfError(AudioQueueAllocateBufferWithPacketDescriptions(mQueue, bufferByteSize, (isFormatVBR ? mNumPacketsToRead : 0), &mBuffers[i]), "AudioQueueAllocateBuffer failed");

基本上我正在尝试访问mAudioData中的信息,但得到错误:

request for member 'mAudioData' in '((AQPlayer*)this)->AQPlayer::mBuffers[i]', which is of non-class type 'AudioQueueBuffer*'

任何帮助非常感谢!

Answer 1

AudioQueueBufferRef是一个AudioQueueBuffer指针.mBuffers是这些的数组.所以提到的要素的成员时mBuffers,你应该用->不.:

printf("%i\n", &mBuffers[i]->mAudioData );

(我猜你可能不想要这&两个 - 由mAudioData持有的地址似乎比在其AudioQueueBuffer结构中该成员的位置打印更有用)