Question

如果我在他关闭的那一刻打开我的应用并告诉我我的测试设备和应用崩溃。

以下是我的LOGCAT错误代码：

      05-16 13:34:02.324 25606-25606/? E/Zygote: v2
      05-16 13:34:02.325 25606-25606/? E/Zygote: accessInfo : 0
      05-16 13:34:04.368 25606-25606/studenty.language.android 
      E/AndroidRuntime: FATAL EXCEPTION: main
      Process: studenty.language.android, PID: 25606
      com.google.firebase.database.DatabaseException: Class 
      studenty.language.android.User does not define a no-argument 
      constructor. If you are using ProGuard, make sure these constructors 
      are not stripped.
      at com.google.android.gms.internal.firebase_database.zzku.zza(Unknown 
      Source)
      at com.google.android.gms.internal.firebase_database.zzkt.zzb(Unknown 
      Source)
      at com.google.android.gms.internal.firebase_database.zzkt.zza(Unknown 
      Source)
      at com.google.firebase.database.DataSnapshot.getValue(Unknown Source)
      at studenty.language.android.MainActivity$2.onDataChange 
      (MainActivity.java:81)
      at com.google.android.gms.internal.firebase_database.zzfc.zza(Unknown 
      Source)
      at com.google.android.gms.internal.firebase_database.zzgx.zzdr(Unknown 
      Source)
      at com.google.android.gms.internal.firebase_database.zzhd.run(Unknown 
      Source)
      at android.os.Handler.handleCallback(Handler.java:751)
      at android.os.Handler.dispatchMessage(Handler.java:95)
      at android.os.Looper.loop(Looper.java:154)
      at android.app.ActivityThread.main(ActivityThread.java:6776)
      at java.lang.reflect.Method.invoke(Native Method)
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run 
      (ZygoteInit.java:1518)
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1408)

班级用户代码：

package studenty.language.android;


public class User {
private String id;
private String name;

public User(String id) {
    this.id = id;
}

public User(String id, String name) {
    this.id = id;
    this.name = name;
}

public String getId() {
    return id;
}

public void setId(String id) {
    this.id = id;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

}

这是因为我需要添加一个默认的无参数，但是如何创建这个默认的无参数以及如何在我的类用户代码上实现它？

实时数据库CRUD错误（android stuido / firebase）

0 个答案: