问题
I have a Firebase project with 2 mobile apps:
- FriendlyChat example from Firebase/Google (messages) - created first
- Grocery Items list (grocery-items) - trying to create second
You can see the messages node already there with some test messages inside.
But when I try to add a child to the appId node, I give it a name "grocery-items" and I click on ADD, but the node does not get added. It just disappears.
Why can't I add the grocery-items node?
回答1:
The Firebase Database is a key-value store. It stores the values of keys at paths in the tree. But it only stores keys when they have an actual value. If there is no value for a key/path, it is immediately deleted.
So if you click the + button, then enter a key and click the Add button, it will delete the first key that you entered because it doesn't have a value.
What you instead should do depends on what you want to accomplish.
To add a single key/value pair:
- click the +
- enter a key/Name
- enter a Value
- click Add
If you want to add a JSON snippet/tree:
- click the +
- enter a key/Name
- click the + next to the (empty) Value
- enter a key/Name for the child
- enter a Value for the child
- click Add
来源：https://stackoverflow.com/questions/38800079/cannot-add-node-to-firebase-through-console