小编sri*_*kla的帖子

所以我是新手,我正在尝试使用Firebase 9.0.0实现电子邮件/密码身份验证.因此,活动执行注册操作或登录操作.

登录操作运行顺利,我可以在Firebase控制台上看到更新.但是当我尝试注册新用户时,会发生此错误,

E/DynamiteModule: Failed to load module descriptor class: Didn't find class "com.google.android.gms.dynamite.descriptors.com.google.firebase.auth.ModuleDescri ptor" on path: DexPathList[[zip file "/data/app/deventree.com.thetimothyinitiative- 2/base.apk"],nativeLibraryDirectories=[/vendor/lib, /system/lib]]

我的设备运行的是Google Play服务9.0.83版.

Android Studio 2.1.1,安装了Google Play服务SDK.我也在控制台中启用了登录方法.

不知道我错过了什么!

所以,我有一个JSON数组,我通过它循环,并添加三个键及其值,我还想删除/删除数组中每个元素的键(subject_id).

怎么去做这个？

s=JSON.parse(subjects.to_json)
s.each do |j|
  j["total_classes"] = total_classes[i]
  j["attended_classes"] = attended_classes[i]
  j["subject_name"] = subject_name[i]
  j["subject_id"] #remove this key, how?
  i=i+1
end

render json: { attendances: s }

我在删除事件监听器时遇到问题.我在收集用户数据后使用在Activity中的onStart()内初始化一个监听器,应用程序向用户显示数据已上传的干杯,然后我调用onBackPressed()方法.

但我注意到,在活动暂停或停止后,侦听器仍在运行,因为它正在创建在onCancelled()事件下调用的toast.

所以我尝试重写onPause和onStop方法.

@Override
public void onPause() {
    super.onPause();
    // Remove post value event listener
      if (mListener != null) {
        mReadReference.removeEventListener(mListener);
       }
}  

但这导致错误:

java.lang.RuntimeException: Unable to pause activity {deventree.com.thetimothyinitiative/deventree.com.thetimothyinitiative.Attendance}: java.lang.NullPointerException: listener must not be null

我想在上传数据之后和活动调用onBackPressed()方法之前删除ValueEventListener

活动代码:

public class Attendance extends Activity {

Map<String, Boolean> td;
ArrayList<String> valu;


private SparseBooleanArray sbArray;

private static final String TAG = "Attendance";

CustomAdapter myAdapter;
ListView listview;

private DatabaseReference mReadReference;
private DatabaseReference mPostReference;
private ValueEventListener mListener;

private Button mButton;
private Button btnAll;
private Button …