fix:crashed when share music on iOS;can't share min program on iOS

example/lib/share_mini_program.dart

@@ -96,7 +96,10 @@ class _ShareMiniProgramPageState extends State<ShareMiniProgramPage> {
         miniProgramType: WeChatShareMiniProgramModel.MINI_PROGRAM_TYPE_RELEASE,
         userName: _userName,
         title: _title,
+        path: _path,
         description: _description,
+        scene: WeChatScene.SESSION,
+        hdImagePath: _thumbnail,
         thumbnail: _thumbnail);
     fluwx.share(model);
   }

ios/Classes/handler/FluwxShareHandler.m

@@ -193,7 +193,7 @@ NSObject <FlutterPluginRegistrar> *_registrar;
 }
 
 - (void)shareMusic:(FlutterMethodCall *)call result:(FlutterResult)result {
-    dispatch_queue_t globalQueue = dispatch_get_global_queue(1, 1);
+    dispatch_queue_t globalQueue = dispatch_get_global_queue(0, 0);
     dispatch_async(globalQueue, ^{
 
         NSString *thumbnail = call.arguments[fluwxKeyThumbnail];
@@ -225,7 +225,7 @@ NSObject <FlutterPluginRegistrar> *_registrar;
 }
 
 - (void)shareVideo:(FlutterMethodCall *)call result:(FlutterResult)result {
-    dispatch_queue_t globalQueue = dispatch_get_global_queue(1, 1);
+    dispatch_queue_t globalQueue = dispatch_get_global_queue(0, 0);
     dispatch_async(globalQueue, ^{
 
         NSString *thumbnail = call.arguments[fluwxKeyThumbnail];
@@ -255,7 +255,7 @@ NSObject <FlutterPluginRegistrar> *_registrar;
 }
 
 - (void)shareMiniProgram:(FlutterMethodCall *)call result:(FlutterResult)result {
-    dispatch_queue_t globalQueue = dispatch_get_global_queue(1, 1);
+    dispatch_queue_t globalQueue = dispatch_get_global_queue(0,0);
     dispatch_async(globalQueue, ^{
 
         NSString *thumbnail = call.arguments[fluwxKeyThumbnail];

ios/Classes/helper/StringUtil.m

@@ -25,7 +25,7 @@
 
 }
 
-- (NSString *)nilToEmpty:(NSString *)string {
++ (NSString *)nilToEmpty:(NSString *)string {
     return string == nil?@"":string;
 }
 @end
\ No newline at end of file

ios/Classes/wechat/WXApiRequestHandler.m

@@ -94,10 +94,10 @@
 
     if ([StringUtil isBlank:musicURL]) {
         ext.musicLowBandUrl = musicLowBandUrl;
-        ext.musicLowBandDataUrl = musicLowBandDataUrl;
+        ext.musicLowBandDataUrl = (musicLowBandDataUrl == (id) [NSNull null]) ? nil : musicLowBandDataUrl ;
     } else {
         ext.musicUrl = musicURL;
-        ext.musicDataUrl = dataURL;
+        ext.musicDataUrl = (dataURL == (id) [NSNull null]) ? nil : dataURL ;
     }
 
 
@@ -205,14 +205,24 @@
                           TagName:(NSString *)tagName
                           InScene:(enum WXScene)scene {
     WXMiniProgramObject *ext = [WXMiniProgramObject object];
-    ext.webpageUrl = webpageUrl;
-    ext.userName = userName;
-    ext.path = path;
-    ext.hdImageData = hdImageData;
+    ext.webpageUrl = (webpageUrl == (id) [NSNull null]) ? nil : webpageUrl;
+    ext.userName =(userName == (id) [NSNull null]) ? nil : userName ;
+    ext.path = (path == (id) [NSNull null]) ? nil : path;
+    ext.hdImageData = (hdImageData == (id) [NSNull null]) ? nil : hdImageData;
     ext.withShareTicket = withShareTicket;
-    ext.miniProgramType = programType;
 
 
+    WXMiniProgramType miniProgramType = WXMiniProgramTypeRelease;
+    if(programType == 0){
+        miniProgramType = WXMiniProgramTypeRelease;
+    } else if(programType == 1){
+        miniProgramType =WXMiniProgramTypeTest;
+    } else if(programType == 2){
+        miniProgramType = WXMiniProgramTypePreview;
+    }
+
+    ext.miniProgramType = miniProgramType;
+
     WXMediaMessage *message = [WXMediaMessage messageWithTitle:(title == (id) [NSNull null]) ? nil : title
                                                    Description:(description == (id) [NSNull null]) ? nil : description
                                                         Object:ext