[WEEX-262][iOS] Add new interface of Instance,which will terminate re…

ios/sdk/WeexSDK/Sources/Model/WXSDKInstance.h

@@ -166,6 +166,13 @@ typedef NS_ENUM(NSInteger, WXErrorCode) {//error.code
  */
 @property (nonatomic, copy) void(^onJSDownloadedFinish)(WXResourceResponse *response,WXResourceRequest *request,NSData *data, NSError* error);
 
+/**
+ * The callback triggered when the bundleJS request finished in the renderWithURL. If the callback returns YES, the render process will terminate.
+ * @return A block that takes response which the server response,request which send to server,data which the server returned and an error
+ */
+@property (nonatomic, copy) BOOL (^onRenderTerminateWhenJSDownloadedFinish)(WXResourceResponse *response,WXResourceRequest *request,NSData *data, NSError* error);
+
+
 /**
  *  the frame of current instance.
  **/

ios/sdk/WeexSDK/Sources/Model/WXSDKInstance.m

@@ -320,6 +320,12 @@ - (void)_renderWithRequest:(WXResourceRequest *)request options:(NSDictionary *)
         WX_MONITOR_SUCCESS_ON_PAGE(WXMTJSDownload, strongSelf.pageName);
         WX_MONITOR_INSTANCE_PERF_END(WXPTJSDownload, strongSelf);
 
+        if (strongSelf.onRenderTerminateWhenJSDownloadedFinish) {
+            if (strongSelf.onRenderTerminateWhenJSDownloadedFinish(response, request, data, error)) {
+                return;
+            }
+        }
+
         [strongSelf _renderWithMainBundleString:jsBundleString];
         [WXTracingManager setBundleJSType:jsBundleString instanceId:weakSelf.instanceId];
     };