嗨，大家好，我想作为标题阅读以前在实时Firebase数据库中创建的单个节点，因此创建了该数据库：
Users
---- UID1
---- Email:
---- Fullname:
---- Phone:
---- Coins:
---- UID2
---- Email:
---- Fullname:
---- Phone:
---- Coins:
所以我的数据库具有如图所示的结构，我需要读取onDataChange并将数据写入TextView中。
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_page_coins_);
FirebaseDatabase database = FirebaseDatabase.getInstance();
DatabaseReference myRef = database.getReference("Utenti");
myRef.child("Rapp Coins %").addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
String coinsRapp = dataSnapshot.getValue(String.class);
mCoins.setText(coinsRapp);
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError) {
}
});
我使用的这种方法不起作用，因为无法获取所需的数据。
我需要使用Coins值：在每个不同的登录用户中，因此每个登录用户都读取他的数据。
我是用来识别每个用户的UID值，我是根据他的手机号码创建的，所以每个用户都有自己的手机号码，可以将他识别为UID。
这是我的全部代码，您可以看到保存UID的数据包含在mPhone中，该数据已保存，然后通过SharedPreferences导入到此活动中。
public class PageCoins_Activity extends AppCompatActivity implements RewardedVideoAdListener {
private static final String TAG = MainActivity.class.getName();
private FirebaseAuth mAuth;
private AdView mBannerTop;
private AdView mBannerBot;
private RewardedVideoAd mRewardedVideoAd;
public double Coins;
double coinsOp = 0.00;
double coinsCl = 0.00;
double coinssum = 0.00;
Button mButton;
Button mPhonebtn;
TextView mCoinscounter;
TextView mCoins;
FirebaseDatabase mDatabase;
EditText mPhoneEdt;
TextView mPhone;
@Override
protected void onStart(){
super.onStart();
updateUI();
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_page_coins_);
FirebaseDatabase database = FirebaseDatabase.getInstance();
DatabaseReference myRef = database.getReference("Utenti");
myRef.child("Rapp Coins %").addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
String coinsRapp = dataSnapshot.getValue(String.class);
mCoins.setText(coinsRapp);
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError) {
}
});
mAuth = FirebaseAuth.getInstance();
initFirebase();
//counter CRD
mCoinscounter = (TextView)findViewById(R.id.Textcoins);
mButton = (Button)findViewById(R.id.btn2);
mPhoneEdt = (EditText)findViewById(R.id.NumberPhEdt);
mPhone = (TextView) findViewById(R.id.NumberPhTxt);
mCoins = (TextView)findViewById(R.id.txtGen);
mPhonebtn = (Button)findViewById(R.id.buttonPhone);
//mPhoneEdt.setVisibility(View.GONE);
//mPhone.setVisibility(View.VISIBLE);
findViewById(R.id.btn2).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (mRewardedVideoAd.isLoaded()) {
mRewardedVideoAd.show();
}
// Write a message to the database
DatabaseReference myRef = mDatabase.getReference();
myRef.child("Utenti").child(mPhone.getText().toString()).child("Rapp Coins Day %").setValue(mCoinscounter.getText().toString());
}
});
mRewardedVideoAd = MobileAds.getRewardedVideoAdInstance(this);
mRewardedVideoAd.setRewardedVideoAdListener(this);
//Set Orientation Portrait
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
// Banner Top View Coins
mBannerTop = (AdView) findViewById(R.id.adViewTopcoins);
AdRequest adRequest = new AdRequest.Builder().setRequestAgent("android_studio:ad_template").build();
mBannerTop.loadAd(adRequest);
// Banner Bot View Coins
mBannerBot = (AdView) findViewById(R.id.adViewBotcoins);
AdRequest adRequest1 = new AdRequest.Builder().setRequestAgent("android_studio:ad_template").build();
mBannerBot.loadAd(adRequest1);
getnumberprefs();
//ADMob Video
loadRewardedVideoAd();
}
private void getnumberprefs() {
SharedPreferences numb = getSharedPreferences(Register_Activity.NUMB, MODE_PRIVATE);
String numberphn = numb.getString(Register_Activity.KEY_NUMB,null);
mPhone.setText(numberphn);
}
//boolean changepgcoins = true;
public void changeNumber(View view) {
/*if (changepgcoins == true){
mPhoneEdt.setVisibility(View.GONE);
mPhone.setVisibility(View.VISIBLE);
changepgcoins = false;
}else{
mPhoneEdt.setVisibility(View.VISIBLE);
mPhone.setVisibility(View.GONE);
changepgcoins = true;
}*/
}
private void initFirebase() {
mDatabase = FirebaseDatabase.getInstance();
}
public void HomeClick(View view){
Intent intenthome = new Intent(this, MainActivity.class);
finish();
startActivity(intenthome);
}
public void displayCrd (double amount){
mCoinscounter.setText(String.format("%.2f", amount));
}
private void loadRewardedVideoAd() {
mRewardedVideoAd.loadAd("ca-app-pub-3940256099942544/5224354917",
new AdRequest.Builder().build());
}
public void logout(View view) {
mAuth.signOut();
updateUI();
}
private void updateUI() {
FirebaseUser currentuser = mAuth.getCurrentUser();
if(currentuser == null){
Intent intTologin = new Intent(this, Login_Activity.class);
finish();
startActivity(intTologin);
}
}
@Override
public void onRewardedVideoAdLoaded() {
Log.d(TAG, "Video Caricato");
}
@Override
public void onRewardedVideoAdOpened() {
}
@Override
public void onRewardedVideoStarted() {
}
@Override
public void onRewardedVideoAdClosed() {
loadRewardedVideoAd();
}
@Override
public void onRewarded(RewardItem rewardItem) {
Toast.makeText(this, " RAPp " + " COINS " + " : " + rewardItem.getAmount(), Toast.LENGTH_LONG).show();
Coins += rewardItem.getAmount();
displayCrd(Coins/40200*100);
}
@Override
public void onRewardedVideoAdLeftApplication() {
}
@Override
public void onRewardedVideoAdFailedToLoad(int i) {
Log.d(TAG, "Caricamento Fallito");
}
@Override
public void onRewardedVideoCompleted() {
loadRewardedVideoAd();
}
@Override
protected void onDestroy() {
if (!isEmpty(mCoins)){
String coinsopen = mCoins.getText().toString();
String coinscounter = mCoinscounter.getText().toString();
coinsOp = Double.parseDouble(String.format(coinsopen.replace(',', '.'), "%.2f"));
coinsCl = Double.parseDouble(String.format(coinscounter.replace(',', '.'), "%.2f"));
coinssum = (coinsOp + coinsCl);
mCoinscounter.setText(String.valueOf(coinssum));
// Write a message to the database
DatabaseReference myRef = mDatabase.getReference();
myRef.child("Utenti").child(mPhone.getText().toString()).child("Rapp Coins %").setValue(mCoinscounter.getText().toString());
}else{
// Write a message to the database
DatabaseReference myRef = mDatabase.getReference();
myRef.child("Utenti").child(mPhone.getText().toString()).child("Rapp Coins %").setValue(mCoinscounter.getText().toString());
}
super.onDestroy();
}
private boolean isEmpty(TextView mCoins) {
String input = mCoins.getText().toString();
return input.length() == 0.00;
}
}
我真的需要有关此问题的解决方案的帮助，因为这是我需要完成的最后一件事，我不能感谢你。
{
"Utenti" : {
"3********4" : {
"E-Mail" : "",
"Full Name" : "",
"Phone" : "",
"Rapp Coins %" : "",
"Rapp Coins Day %" : ""
},
"3********1" : {
"E-Mail" : "",
"Full Name" : "",
"Phone" : "",
"Rapp Coins %" : "",
"Rapp Coins Day %" : ""
},
}
}
这是我组成的数据库。