fix windows crash bugs

Author: oneSitDown

Agora-Unreal-SDK-CPP-Example/Source/AgoraExample/AgoraVideoWidget.cpp

@@ -190,6 +190,11 @@ void UAgoraVideoWidget::onUserOffline(agora::rtc::uid_t uid, agora::rtc::USER_OF
 void UAgoraVideoWidget::onLeaveChannel(const agora::rtc::RtcStats& stats) {
 	AsyncTask(ENamedThreads::GameThread, [=]()
 	{
+		if (bIsDestruct)
+		{
+			UE_LOG(LogTemp, Warning, TEXT("UVideoWidget::onLeaveChannel bIsDestruct"));
+			return;
+		}
 		UE_LOG(LogTemp, Warning, TEXT("UVideoWidget::onLeaveChannel"));
 		agora::rtc::VideoCanvas videoCanvas;
 		videoCanvas.view = nullptr;
@@ -318,6 +323,8 @@ void UAgoraVideoWidget::NativeDestruct() {
 		delete RtcEngineProxy;
 
 		RtcEngineProxy = nullptr;
+
+		bIsDestruct = true;
 	}
 
 }

Agora-Unreal-SDK-CPP-Example/Source/AgoraExample/AgoraVideoWidget.h

@@ -140,6 +140,8 @@ class AGORAEXAMPLE_API UAgoraVideoWidget : public UBaseAgoraUserWidget, public a
 
 	FSlateBrush EmptyBrush;
 
+	bool bIsDestruct = false;
+
 	void InitAgoraEngine(FString APP_ID, FString TOKEN, FString CHANNEL_NAME);
 
 	void SetUpUIEvent();

Agora-Unreal-SDK-CPP-Example/Source/AgoraExample/ProcessAudioRawDataWidget.cpp

@@ -2,8 +2,7 @@
 
 
 #include "ProcessAudioRawDataWidget.h"
-#include <string>
-#import <Foundation/Foundation.h>
+
 void UProcessAudioRawDataWidget::InitAgoraWidget(FString APP_ID, FString TOKEN, FString CHANNEL_NAME)
 {
 	InitConfig();

Agora-Unreal-SDK-CPP-Example/Source/AgoraExample/ProcessAudioRawDataWidget.h

@@ -15,6 +15,9 @@
 #include "AndroidPermission/Classes/AndroidPermissionFunctionLibrary.h"
 #endif
 #include <string>
+#if PLATFORM_IOS
+#import <Foundation/Foundation.h>
+#endif
 #include "ProcessAudioRawDataWidget.generated.h"
 
 using namespace agora::rtc;