fix: 优化 picker 通讯

src/platforms/app-plus/view/components/picker/page.js

@@ -46,14 +46,14 @@ function addEventListener (pageId, callback) {
 class Page {
   constructor (webview) {
     this.webview = webview
-  }
+  }
 
   sendMessage (data) {
-    const message = {
+    const message = JSON.parse(JSON.stringify(({
       __message: {
         data
       }
-    }
+    })))
     const id = this.webview.id
     if (BroadcastChannel_) {
       const channel = new BroadcastChannel_(id)
@@ -61,7 +61,7 @@ class Page {
     } else {
       plus_.webview.postMessageToUniNView(message, id)
     }
-  }
+  }
 
   close () {
     this.webview.close()