如何使用firebase作为数据库在android中获取附近的用户名（） _数据库

少年恃险若平地，独倚长剑凌清秋。这篇文章主要讲述如何使用firebase作为数据库在android中获取附近的用户名？相关的知识，希望能为你提供帮助。
【如何使用firebase作为数据库在android中获取附近的用户名（）】我在下面添加了我的firebase数据库的屏幕截图。我正在使用geofire获取存储在electriciansAvailable中的附近用户位置lat / lng。我已经使用适配器显示ui中附近用户的列表，我能够显示密钥存储在电工中可用。
但我不想显示密钥，而是想显示用户的名字（例如：-san@gmail.com）。我很久以来一直坚持这个，请有人告诉我如何显示列表表单中附近用户名的名称？
下面我附上了我的截图和代码。它在db中将电工值更新为true但是电气名称在listview中显示为空白。我已经上传了屏幕截图和代码。

fun getElectriciansAround(){ getElectriciansArounStarted = true val customerId: String = FirebaseAuth.getInstance().currentUser!!.uid val driversLocation:DatabaseReference=FirebaseDatabase.getInstance().reference.child("electricianAvailable") val geofire:GeoFire= GeoFire(driversLocation) val geoQuery:GeoQuery = geofire.queryAtLocation(GeoLocation(mLastLocation.latitude,mLastLocation.longitude), 10000.0) geoQuery.addGeoQueryEventListener(object : GeoQueryEventListener{ override fun onKeyEntered(key: String?, location: GeoLocation?) { val electricianRef:DatabaseReference=FirebaseDatabase.getInstance().reference.child("users").child("Electricians").child(key!!) driversLocation.addListenerForSingleValueEvent(object :ValueEventListener{ override fun onCancelled(p0: DatabaseError) { TODO("not implemented") //To change body of created functions use File | Settings | File Templates. } override fun onDataChange(dataSnapshot: DataSnapshot) { if(dataSnapshot.exists() & & dataSnapshot.childrenCount> 0){ for(i in 0 until dataSnapshot.childrenCount){ electricianRef.child(customerId).setValue(true) getDriverName("Electricians",key!!) electricianNames= arrayOf(mElectricianName) val adapter= ArrayAdapter(this@CustomerElectricianHome, android.R.layout.simple_expandable_list_item_1, electricianNames) mListViewElectricians.adapter=adapter } } } }) Run code snippet

var mElectricianName:String="" private fun getDriverName(ElectricianName: String, key: String) { val mDriverNameDb:DatabaseReference=FirebaseDatabase.getInstance().reference.child("users").child(ElectricianName).child(key) mDriverNameDb.addListenerForSingleValueEvent(object :ValueEventListener{ override fun onCancelled(p0: DatabaseError) { } override fun onDataChange(dataSnapshot: DataSnapshot) { if(dataSnapshot.exists()){ val map:Map< *,*> = dataSnapshot.value as Map< *,*> if(map["name"]!=null){ mElectricianName= map["name"].toString() } } } }) }

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答案您需要使用GeoQueryEventListener.onKeyEntered方法内部的Firebase实时数据库中的额外读取来查找其他用户数据。
就像是：

geoQuery.addGeoQueryEventListener(new GeoQueryEventListener() { @Override public void onKeyEntered(String key, GeoLocation location) { System.out.println(String.format("Key %s entered the search area at [%f,%f]", key, location.latitude, location.longitude)); DatabaseReference electriciansRef = FirebaseDatabase.getInstance().getReference("users/Electricians"); electriciansRef.child(key).addListenerForSingleValueEvent(new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { String name = dataSnapshot.child("name").getValue(String.class); System.out.println(String.format("Electrician name: %s", name)); }@Override public void onCancelled(DatabaseError databaseError) { throw databaseError.toException(); } }) }...@Override public void onGeoQueryError(DatabaseError error) { System.err.println("There was an error with this query: " + error); } });

或者在Kotlin：

geoQuery.addGeoQueryEventListener(object:GeoQueryEventListener() { fun onKeyEntered(key:String, location:GeoLocation) { println(String.format("Key %s entered the search area at [%f,%f]", key, location.latitude, location.longitude)) val electriciansRef = FirebaseDatabase.getInstance().getReference("users/Electricians") electriciansRef.child(key).addListenerForSingleValueEvent(object:ValueEventListener() { fun onDataChange(dataSnapshot:DataSnapshot) { val name = dataSnapshot.child("name").getValue(String::class.java) println(String.format("Electrician name: %s", name)) } fun onCancelled(databaseError:DatabaseError) { throw databaseError.toException() } }) }...fun onGeoQueryError(error:DatabaseError) { System.err.println("There was an error with this query: " + error) } })