windows compile error

Author: sbd021

windows/APIExample/APIExample/Advanced/AudioMixing/CAgoraAudioMixingDlg.h

@@ -76,7 +76,7 @@ class CAudioMixingEventHandler : public IRtcEngineEventHandler
 		SDK triggers this callback.
 	 */
 	virtual void onRemoteVideoStateChanged(uid_t uid, REMOTE_VIDEO_STATE state, REMOTE_VIDEO_STATE_REASON reason, int elapsed) override;
-	virtual void onAudioMixingStateChanged(AUDIO_MIXING_STATE_TYPE state, AUDIO_MIXING_REASON_TYPE reason)override;
+	virtual void  onAudioMixingStateChanged(AUDIO_MIXING_STATE_TYPE state, AUDIO_MIXING_REASON_TYPE reason) override;
 private:
 	HWND m_hMsgHanlder;
 };