如何从 Firebase 检索数据并将其设置为图表的字符串和整数

Question

Good morning/afternoon/evening I just need help on how can I change the data of string and value from firebase to my code or chart. I'm currently using preset values as shown (String "skyobject" and int"500,300,600,123" and hoping to use data from my firebase which is shown in the image. thank you for helping me I'm new to this android studio thing so I'm grateful for any help that I can get. thank you so much in advance for those people who will help me

public class MainActivity extends AppCompatActivity {
    AnyChartView anyChartView;
    Button btn;
    DatabaseReference reff;


    String [] skyobject = {"sun","moon","stars","planets"};
    int[] datas = {500,300,600,123};


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        anyChartView =( AnyChartView) findViewById(R.id.any_chart_view);
        setupPieChart();


    }
    public void setupPieChart() {
        Pie pie = AnyChart.pie();
        List<DataEntry> dataEntries = new ArrayList<>();

        for (int i=0;i<skyobject.length;i++){
            dataEntries.add(new ValueDataEntry(skyobject[i],datas[i]));


        }
        pie.data(dataEntries);
        anyChartView.setChart(pie);

    }
}

Edited code with the given code of @Alex Mamo

package com.javapapers.androidchartapp;

import android.os.Bundle;
import android.util.Log;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import com.anychart.AnyChart;
import com.anychart.AnyChartView;
import com.anychart.chart.common.dataentry.DataEntry;
import com.anychart.chart.common.dataentry.ValueDataEntry;
import com.anychart.charts.Pie;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;
import com.javapapers.androidchartapp.R;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    AnyChartView anyChartView;

    DatabaseReference rootRef;


    String [] skyobject = {"sun","moon","stars","planets"};
    int[] datas = {500,300,600,123};


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
        ValueEventListener valueEventListener = new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                for(DataSnapshot ds : dataSnapshot.getChildren()) {
                    String key = ds.getKey();
                    String name = ds.getValue(String.class);
                    Log.d("TAG", key + ": " + name);
                }
            }

            @Override
            public void onCancelled(@NonNull DatabaseError databaseError) {
                Log.d(TAG, databaseError.getMessage()); //Don't ignore errors!
            }
        };
        rootRef.addListenerForSingleValueEvent(valueEventListener);
        anyChartView = findViewById(R.id.any_chart_view);
        setupPieChart();


    }
    public void setupPieChart() {
        Pie pie = AnyChart.pie();
        List<DataEntry> dataEntries = new ArrayList<>();

        for (int i=0;i<skyobject.length;i++){
            dataEntries.add(new ValueDataEntry(skyobject[i],datas[i]));

        }
        pie.data(dataEntries);
        anyChartView.setChart(pie);

    }

This is the Error in the Logcat

    --------- beginning of crash
E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.javapapers.androidchartapp, PID: 22809
    java.lang.RuntimeException: Uncaught exception in Firebase Database runloop (3.0.0). Please report to firebase-database-client@google.com
        at com.google.firebase.database.android.AndroidPlatform$1$1.run(com.google.firebase:firebase-database@@16.0.4:98)
        at android.os.Handler.handleCallback(Handler.java:751)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:154)
        at android.app.ActivityThread.main(ActivityThread.java:6776)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1520)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1410)
     Caused by: java.lang.NoClassDefFoundError: Failed resolution of: Lcom/google/firebase/FirebaseApp$IdTokenListener;
        at com.google.firebase.database.android.AndroidPlatform.newAuthTokenProvider(com.google.firebase:firebase-database@@16.0.4:112)
        at com.google.firebase.database.core.Context.ensureAuthTokenProvider(com.google.firebase:firebase-database@@16.0.4:246)
        at com.google.firebase.database.core.Context.initServices(com.google.firebase:firebase-database@@16.0.4:98)
        at com.google.firebase.database.core.Context.freeze(com.google.firebase:firebase-database@@16.0.4:77)
        at com.google.firebase.database.core.RepoManager.createLocalRepo(com.google.firebase:firebase-database@@16.0.4:92)
        at com.google.firebase.database.core.RepoManager.createRepo(com.google.firebase:firebase-database@@16.0.4:42)
        at com.google.firebase.database.FirebaseDatabase.ensureRepo(com.google.firebase:firebase-database@@16.0.4:357)
        at com.google.firebase.database.FirebaseDatabase.getReference(com.google.firebase:firebase-database@@16.0.4:201)
        at com.javapapers.androidchartapp.MainActivity.onCreate(MainActivity.java:42)
        at android.app.Activity.performCreate(Activity.java:6955)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1126)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2927)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3045)
        at android.app.ActivityThread.-wrap14(ActivityThread.java)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1642)
        at android.os.Handler.dispatchMessage(Handler.java:102)
        at android.os.Looper.loop(Looper.java:154) 
        at android.app.ActivityThread.main(ActivityThread.java:6776) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1520) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1410) 
     Caused by: java.lang.ClassNotFoundException: Didn't find class "com.google.firebase.FirebaseApp$IdTokenListener" on path: DexPathList[[zip file "/data/app/com.javapapers.androidchartapp-1/base.apk"],nativeLibraryDirectories=[/data/app/com.javapapers.androidchartapp-1/lib/arm64, /system/lib64, /vendor/lib64]]
        at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:380)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:312)
        at com.google.firebase.database.android.AndroidPlatform.newAuthTokenProvider(com.google.firebase:firebase-database@@16.0.4:112) 
        at com.google.firebase.database.core.Context.ensureAuthTokenProvider(com.google.firebase:firebase-database@@16.0.4:246) 
        at com.google.firebase.database.core.Context.initServices(com.google.firebase:firebase-database@@16.0.4:98) 
        at com.google.firebase.database.core.Context.freeze(com.google.firebase:firebase-database@@16.0.4:77) 
        at com.google.firebase.database.core.RepoManager.createLocalRepo(com.google.firebase:firebase-database@@16.0.4:92) 
        at com.google.firebase.database.core.RepoManager.createRepo(com.google.firebase:firebase-database@@16.0.4:42) 
        at com.google.firebase.database.FirebaseDatabase.ensureRepo(com.google.firebase:firebase-database@@16.0.4:357) 
        at com.google.firebase.database.FirebaseDatabase.getReference(com.google.firebase:firebase-database@@16.0.4:201) 
        at com.javapapers.androidchartapp.MainActivity.onCreate(MainActivity.java:42) 
        at android.app.Activity.performCreate(Activity.java:6955) 
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1126) 
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2927) 
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3045) 
        at android.app.ActivityThread.-wrap14(ActivityThread.java) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1642) 
        at android.os.Handler.dispatchMessage(Handler.java:102) 
        at android.os.Looper.loop(Looper.java:154) 
        at android.app.ActivityThread.main(ActivityThread.java:6776) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1520) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1410)

image of my database click here

image of the pie chart output click here

edited with the given codes down there got error with the TAG click here

Answer 1

To get the keys and values for those properties, please use the following lines of code:

DatabaseReference rootRef = FirebaseDatabase.getInstance().getReference();
ValueEventListener valueEventListener = new ValueEventListener() {
    @Override
    public void onDataChange(DataSnapshot dataSnapshot) {
        for(DataSnapshot ds : dataSnapshot.getChildren()) {
            String key = ds.getKey();
            String name = ds.getValue(String.class);
            Log.d("TAG", key + ": " + name);
        }
    }

    @Override
    public void onCancelled(@NonNull DatabaseError databaseError) {
        Log.d(TAG, databaseError.getMessage()); //Don't ignore errors!
    }
};
rootRef.addListenerForSingleValueEvent(valueEventListener);

The result in your logcat will be:

Moon: 300
Planets: 123
Stars: 600
Sun:  500