Question

我的错误：

E/UncaughtException: com.google.firebase.database.DatabaseException: Can't convert object of type java.lang.String to type com.stitch.fractions.Profile.userInfo.UserInformation
                     at com.google.android.gms.internal.zzamy.zze(Unknown Source)
                     at com.google.android.gms.internal.zzamy.zzb(Unknown Source)
                     at com.google.android.gms.internal.zzamy.zza(Unknown Source)
                     at com.google.firebase.database.DataSnapshot.getValue(Unknown Source)
                     at com.stitch.fractions.Scoreboard.activity.activity.ScoreboardActivity$1.onDataChange(ScoreboardActivity.java:49)
                     at com.google.firebase.database.Query$1.onDataChange(Unknown Source)
                     at com.google.android.gms.internal.zzajp.zza(Unknown Source)
                     at com.google.android.gms.internal.zzakp.zzcxi(Unknown Source)
                     at com.google.android.gms.internal.zzaks$1.run(Unknown Source)
                     at android.os.Handler.handleCallback(Handler.java:743)
                     at android.os.Handler.dispatchMessage(Handler.java:95)
                     at android.os.Looper.loop(Looper.java:150)
                     at android.app.ActivityThread.main(ActivityThread.java:5546)
                     at java.lang.reflect.Method.invoke(Native Method)
                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:794)
                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:684)
I/FA: Tag Manager is not found and thus will not be used
I/Process: Sending signal. PID: 22183 SIG: 9
Disconnected from the target VM, address: 'localhost:8604', transport: 'socket'

我的活动类：

public class ScoreboardActivity extends AppCompatActivity {
    private FirebaseAuth mAuth;
    private DatabaseReference dbRef;
    private ArrayList<UserInformation> mArrayUserInfo = new ArrayList<>();
    private String userId;

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

        mAuth = FirebaseAuth.getInstance();
        userId = mAuth.getCurrentUser().getUid();
        dbRef = FirebaseDatabase.getInstance().getReference();
        displayData();
    }

    public void displayData() {
        dbRef.addListenerForSingleValueEvent(new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                for (DataSnapshot users : dataSnapshot.getChildren()) {
                    for (DataSnapshot user : users.getChildren()) {
                        if (user.getKey().equals(userId)) {
                            for (DataSnapshot sItem : user.getChildren()) {
                                if (!(sItem.getKey().equals("age"))) {
                                    UserInformation scoreActivity = sItem.getValue(UserInformation.class);
                                    mArrayUserInfo.add(scoreActivity);
                                    ScoreAdapter sAdapter = new ScoreAdapter(getApplicationContext(), mArrayUserInfo);

                                    ListView listScore = (ListView)findViewById(R.id.lvScore);
                                        listScore.setAdapter(sAdapter);
                                }
                            }
                        }
                    }
                }
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {
                Toast.makeText(ScoreboardActivity.this, "Error Kid", Toast.LENGTH_SHORT).show();
            }
        });
    }
}

这是我的模型类：

public class UserInformation {
    public String name;
    public String age;
    public String score;


    public UserInformation() {

    }

    public UserInformation(String name, String age, String score) {
        this.name = name;
        this.age = age;
        this.score = score;
    }

    public String getName() {
        return name;
    }

    public String getAge() {
        return age;
    }

    public String getScore(){
        return score;
        }
    }
}

以下是我写给数据库的方式：

public class ProfileActivity extends AppCompatActivity {

private FirebaseAuth firebaseAuth;

private TextView mUserEmail, mUserScore;
private Button mBtnLogOut, mBtnSave, mBtnScore;
private EditText mEdtProfileName, mEdtProfileAge;

private DatabaseReference dbRefer;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_profile);
    initComponent();
    getCurrentUser();
    checkCurrentUser();
    firebaseDatabase();


    mBtnLogOut.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            firebaseAuth.signOut();
            finish();
            Intent back = new Intent(ProfileActivity.this, HomeActivity.class);
            startActivity(back);
            Toast.makeText(ProfileActivity.this, "Good Bye", Toast.LENGTH_SHORT).show();
        }
    });

    mBtnSave.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            saveUserInfor();
        }
    });

    mBtnScore.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent game = new Intent(ProfileActivity.this, ScoreboardActivity.class);
            startActivity(game);

        }
    });

}

public void initComponent() {
    mBtnLogOut = (Button) findViewById(R.id.btnOut);
    mUserEmail = (TextView) findViewById(R.id.userEmail);
    firebaseAuth = FirebaseAuth.getInstance();
    mEdtProfileName = (EditText) findViewById(R.id.edtProfileName);
    mEdtProfileAge = (EditText) findViewById(R.id.edtProfileAge);
    mBtnSave = (Button) findViewById(R.id.btnSave);
    mUserScore = (TextView) findViewById(R.id.userScore);
    mBtnScore = (Button) findViewById(R.id.btnScore);

}

public void checkCurrentUser() {
    firebaseAuth = FirebaseAuth.getInstance();
    if (firebaseAuth.getCurrentUser() == null) {
        finish();
        Intent home = new Intent(ProfileActivity.this, HomeActivity.class);
        startActivity(home);
    }
}

public void getCurrentUser() {
    FirebaseUser user = firebaseAuth.getCurrentUser();
    mUserEmail.setText("Current User: " + user.getEmail());

}

public void firebaseDatabase() {
    dbRefer = FirebaseDatabase.getInstance().getReference();
    mEdtProfileName.getText().toString().trim();
    mEdtProfileAge.getText().toString().trim();
}

public void saveUserInfor() {
    String name = mEdtProfileName.getText().toString().trim();
    String age = mEdtProfileAge.getText().toString().trim();

    SharedPreferences prefsName = getSharedPreferences("Name", MODE_PRIVATE);
    SharedPreferences.Editor editorName = prefsName.edit();
    editorName.putString("sentname", name);
    editorName.commit();

    SharedPreferences prefsAge = getSharedPreferences("Age", MODE_PRIVATE);
    SharedPreferences.Editor editorAge = prefsAge.edit();
    editorAge.putString("sentage", age);
    editorAge.commit();

    SharedPreferences prefs = getSharedPreferences("Data",MODE_PRIVATE);
    String data = prefs.getString("time","hi");

    if (TextUtils.isEmpty(name)) {
        mEdtProfileName.setError("Empty Field !!!");
        return;
    }
    if (TextUtils.isEmpty(age)) {
   mEdtProfileAge.setError("Empty Field !!!");
        return;
    }
        UserInformation userInfo = new UserInformation(name, age, data);
        FirebaseUser user = firebaseAuth.getCurrentUser();
        dbRefer.child("User").child(user.getUid()).setValue(userInfo);
        Toast.makeText(this, "Data Saved", Toast.LENGTH_SHORT).show();
}
}

我的适配器类：

public class ScoreAdapter extends BaseAdapter {
private Context mContext;
private LayoutInflater mScoreInflater;
private ArrayList<UserInformation> mUserInfo;

public ScoreAdapter(Context mContext, ArrayList<UserInformation> userInfo) {
    this.mContext = mContext;
    this.mScoreInflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    this.mUserInfo = userInfo;
}

@Override
public int getCount() {
    return mUserInfo.size();
}

@Override
public Object getItem(int position) {
    return mUserInfo.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    classScoreHolder holder;

    if (convertView == null) {

        convertView = mScoreInflater.inflate(R.layout.scoreboard_row, parent, false);

        holder = new classScoreHolder();
        holder.mTvScoreName = (TextView) convertView.findViewById(R.id.tvScoreName);
        holder.mTvScorePoint = (TextView) convertView.findViewById(R.id.tvScorePoint);
        convertView.setTag(holder);
    } else {
        holder = (classScoreHolder) convertView.getTag();
    }

    TextView tvScoreName = holder.mTvScoreName;
    TextView tvScorePoint = holder.mTvScorePoint;

    UserInformation getUserInfo = (UserInformation) getItem(position);

    tvScoreName.setText("User Name: " + getUserInfo.getName());
    tvScorePoint.setText("User Score: " + getUserInfo.getScore());

    return convertView;
}

private static class classScoreHolder {
    public TextView mTvScoreName;
    public TextView mTvScorePoint;
}

当前数据库有名称，年龄和分数。我想要获得的只是从Firebase数据库到Customlistview的名称和年龄。

Answer 1

不是100％肯定，但看起来你的层次结构太过分了。如果我是对的，这将简化您的代码。试试这个：

public void displayData() {
    dbRef.addListenerForSingleValueEvent(new ValueEventListener() {
        @Override
        public void onDataChange(DataSnapshot dataSnapshot) {
            for (DataSnapshot users : dataSnapshot.getChildren()) {
                for (DataSnapshot user : users.getChildren()) {
                    if (user.getKey().equals(userId)) {
                        UserInformation scoreActivity = user.getValue(UserInformation.class);
                        mArrayUserInfo.add(scoreActivity);
                    }
                }
            }
            ScoreAdapter sAdapter = new ScoreAdapter(getApplicationContext(), mArrayUserInfo);
            ListView listScore = (ListView)findViewById(R.id.lvScore);
            listScore.setAdapter(sAdapter);
        }

        @Override
        public void onCancelled(DatabaseError databaseError) {
            Toast.makeText(ScoreboardActivity.this, "Error Kid", Toast.LENGTH_SHORT).show();
        }
    });
}

Firebase检索数据到customlistview [Android]

1 个答案: