意图错误 android 有人尝试解决此错误并帮助我，检查 SS，我尝试了三种方法来解决但没有用

Question

在 FirebaseAdapter 中，我在 ViewHolderClass 中创建了 intent 视图

     @Override
        protected void onBindViewHolder(@NonNull MyviewHolder holder, int position, @NonNull DataClass model) {
            holder.name.setText(String.valueOf(model.getName()));
            holder.Nickname.setText(model.getNickname());
            Log.d(TAG, "onBindViewHolder: Now Bind method executing");
           holder.v.setOnClickListener(new View.OnClickListener() {
               @Override
               public void onClick(View v) {
                   Intent i = new Intent(v.getContext(),SecondActivity.class);
                   i.putExtra("Users",getRef(position).getKey());
                   mContext.startActivity(i);
    
               }
           });
        }

In MainActivity:

      mAdapter = new FirebaseAdapter(options,MainActivity.this);

In SecondActivity
  

      public class SecondActivity extends AppCompatActivity {
            DatabaseReference ref;
         TextView gname,gnickname;
            @Override
            protected void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.activity_second);
                gname = (TextView)findViewById(R.id.gettingname);
                gnickname =(TextView)findViewById(R.id.gettingnickname);
        
                ref = FirebaseDatabase.getInstance().getReference().child("Users");
        
                String Users = getIntent().getStringExtra("Users");
        
               ref.child(Users).addValueEventListener(new ValueEventListener() {
                    @Override
                    public void onDataChange(@NonNull DataSnapshot snapshot) {
                        if(snapshot.exists()){
                            String name = Objects.requireNonNull(snapshot.child("Name").getValue()).toString();
                            String nick = Objects.requireNonNull(snapshot.child("Nick").getValue()).toString();
        
                            gname.setText(name);
                            gnickname.setText(nick);
                        }
                    }
        
                    @Override
                    public void onCancelled(@NonNull DatabaseError error) {
        
                    }
                });
      
    
Error:
  Process: com.example.firebasesearchrec, PID: 20933
    java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference
        at com.example.firebasesearchrec.SecondActivity.onDataChange(SecondActivity.java:34)
        at com.google.firebase.database.core.ValueEventRegistration.fireEvent(ValueEventRegistration.java:75)

....................... 谢谢....................... ..................................................... ..................................................... ...................................

Answer 1

第三种方法使用这个。

v.getContext().startActivity(i);

Answer 2

首先，获取Activity上下文

Context mContext;
    
Get context from constructor

public FirbaseAdapter(FirebaseRecyclerOptions<DataClass> options, Context context) {
    super(options);
    this.mContext = context;

}

终于

        Intent i = new Intent(view.getContext(), SecondActivity.class);
        i.putExtra("Users",getRef(position).getKey());
        mContext.startActivity(i);

或者，如果您想要快速简单的解决方案，请试试这个

        Intent i = new Intent(view.getContext(), SecondActivity.class);
        i.putExtra("Users",getRef(position).getKey());
        view.getContext().startActivity(i);

意图错误 android 有人尝试解决此错误并帮助我，检查 SS，我尝试了三种方法来解决但没有用

Getting error in intent android somebody try to solve this error and help me,Check out SS,I tried three methods to solve but no use

java

android

android-intent

firebase

android-recyclerview