使用Firebase数据填充Android微调器 [英] Populating Android spinner with Firebase Data

问题描述

在将 propertyAddress 从我的 properties 表填充到 MaintenanceActivity 中的微调框时，我遇到了一些问题.

问题本身不在于代码内，而是与可以使用Firebase控制台进行修改的数据库规则有关.

目前，我的规则如下:

  {规则":{维护" : {"$ uid":{".read":"$ uid === auth.uid"，".write":"$ uid === auth.uid"}}}} 

在记录维护查询时允许基于用户的身份验证.

但是，仅当规则如下时，微调器才会填充propertyAddress:

  {规则":{".read":"true"，".write":"true"}} 

我想知道我需要对规则做些什么，以使我的微调框 spinnerProperty 可以访问数据库的 properties 部分./p>

这是 MaintenanceActivity 的代码摘录:

维护活动

  fDatabaseRoot.child("properties").addListenerForSingleValueEvent(new ValueEventListener(){@Override公共无效onDataChange(DataSnapshot dataSnapshot){dataSnapshot.getChildren()至//初始化数组最终List< String>propertyAddressList = new ArrayList< String>();对于(DataSnapshot addressSnapshot:dataSnapshot.getChildren()){字符串propertyAddress = addressSnapshot.child("propertyAddress").getValue(String.class);如果(propertyAddress！= null){propertyAddressList.add(propertyAddress);}}Spinner spinnerProperty =(Spinner)findViewById(R.id.spinnerProperty);ArrayAdapter< String>addressAdapter = new ArrayAdapter< String>(MaintenanceActivity.this，android.R.layout.simple_spinner_item，propertyAddressList);addressAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);spinnerProperty.setAdapter(addressAdapter);}@Override公共无效onCancelled(DatabaseError databaseError){}}); 

这是我的属性表的图像:

在此方面的任何帮助将不胜感激.

同样，与代码本身无关，仅与数据库规则无关.

解决方案

我已经更新了Firebase数据库的规则，以包括对 properties 节点的读取/写入功能.

  {规则":{维护" : {"$ uid":{".read":"$ uid === auth.uid"，".write":"$ uid === auth.uid"}}，特性" : {".read":是的，".write":false}}} 

I am having a few issues populating the propertyAddress from my properties table to to a spinner in my MaintenanceActivity.

The issue itself does not lie within the code, rather with the Database Rules that can be amended using the Firebase Console.

Currently, my rules are like so:

{
  "rules": {
    "maintenance" : {
      "$uid" : {
        ".read": "$uid === auth.uid",
        ".write": "$uid === auth.uid"
      }
    }
  }
}

Which allows user-based authentication when logging maintenance queries.

However, the spinner will only populate with the propertyAddress when the rules are as follows:

{
  "rules": {
    ".read":"true",
    ".write": "true"
  }
}

I'm wondering what I need to do to my rules in order to allow my spinner, spinnerProperty, to have access to the properties part of my DB.

Here is the code extract for MaintenanceActivity:

MaintenanceActivity

fDatabaseRoot.child("properties").addListenerForSingleValueEvent(new ValueEventListener() {
    @Override
    public void onDataChange(DataSnapshot dataSnapshot) {
        dataSnapshot.getChildren() to
        // initialize the array
        final List<String> propertyAddressList = new ArrayList<String>();

        for (DataSnapshot addressSnapshot: dataSnapshot.getChildren()) {
            String propertyAddress = addressSnapshot.child("propertyAddress").getValue(String.class);
            if (propertyAddress!=null){
                propertyAddressList.add(propertyAddress);
            }
        }

        Spinner spinnerProperty = (Spinner) findViewById(R.id.spinnerProperty);
        ArrayAdapter<String> addressAdapter = new ArrayAdapter<String>(MaintenanceActivity.this, android.R.layout.simple_spinner_item, propertyAddressList);
        addressAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinnerProperty.setAdapter(addressAdapter);
    }

    @Override
    public void onCancelled(DatabaseError databaseError) {

    }
});

Here is an image of my properties table:

Any help on this would be much appreciated.

Again, not an issue with the code itself, only with the rules of the DB.

解决方案

I have updated the rules for my Firebase Database to include read/write functionality for the properties node.

    {
  "rules": {
    "maintenance" : {
      "$uid" : {
    ".read": "$uid === auth.uid",
    ".write": "$uid === auth.uid"
  }
},
    "properties" : {
      ".read": true,
      ".write": false
    }
}
}

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