斯威夫特火力地堡：从火力地堡查询

我期待与特定mealID更新read属性true所有对象。我曾尝试这样的：

if let selectedIndexPath = tableView.indexPathForSelectedRow { 
       meals[(selectedIndexPath as NSIndexPath).row].unreadNotification=false 
       let mealId = mealIds[(selectedIndexPath as NSIndexPath).row] 
       let notificationsRef = ref.child("notifications") 
       //get all notifications with this mealId 
       var mealNotifications = notificationsRef.queryOrdered(byChild: "mealId").queryEqual(toValue: mealId) 
       //notificationRef.updateChildValues(["read":true]) 
      }

该查询输出正确的通知对象，我只是不知道如何（使用mealNotifications）更新这些特定对象。有任何想法吗？

EDIT

我已经加入一个观察事件，但是我没有在输出接收到任何对象（我期待一个单输出）。我相信这是因为我正在查看通知ID级别，而不是mealID级别。我怎样才能纠正这个查询？

if let selectedIndexPath = tableView.indexPathForSelectedRow { 
       meals[(selectedIndexPath as NSIndexPath).row].unreadNotification=false 
       let mealId = mealIds[(selectedIndexPath as NSIndexPath).row] 
       let notificationsRef = ref.child("notifications") 
       //get all notifications with this mealId 
       var mealNotifications = notificationsRef.queryOrdered(byChild: "mealId").queryEqual(toValue: mealId).observe(.value, with: {snapshot in 
        print("MEALS:",snapshot) 
        }) 
       //notificationRef.updateChildValues(["read":true]) 
      }

来源

2016-10-02 benjanisa

你需要附加一个观察者，环比儿童和调用'child.ref.updateChildValues（）'。请参阅http://stackoverflow.com/questions/36821000/how-to-update-firebase-query –

谢谢。看来我的查询是不正确的，因为我正在尝试查看notificationsRef以下的级别。有没有指定byChild参数应该降低的方法？ – benjanisa

我在 – benjanisa

以下工作：

if let selectedIndexPath = tableView.indexPathForSelectedRow { 
       meals[(selectedIndexPath as NSIndexPath).row].unreadNotification=false 
       let mealId = mealIds[(selectedIndexPath as NSIndexPath).row] 
       let notificationsRef = ref.child("notifications") 
       //get all notifications with this mealId 
       var mealNotifications = notificationsRef.queryOrdered(byChild: "mealID").queryEqual(toValue: mealId).observe(.value, with: {snapshot in 
        let enumerator = snapshot.children 
        while let rest = enumerator.nextObject() as? FIRDataSnapshot { 
         notificationsRef.child(rest.key).child("read").setValue(true) 
         } 
         }) 
        tableView.reloadRows(at: [selectedIndexPath], with: .none) 
       }

来源

2016-10-02 22:32:23 benjanisa

斯威夫特火力地堡：从火力地堡查询

回答

相关问题