Question

活动显示已注册用户的列表。触摸任何用户后，它会与该用户聊天，但问题是它在每个用户中显示相同的消息。 MainActivity.java

public class MainActivity extends BaseActivity {
ListView usersList;
private DatabaseReference mDatabaseUser;
ArrayList<String> list=new ArrayList<>();
private DatabaseReference root = FirebaseDatabase.getInstance().getReference().getRoot();

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    mDatabaseUser = FirebaseDatabase.getInstance().getReference("users");

    usersList = (ListView)findViewById(R.id.usersList);
    final ArrayAdapter<String> adapter=new ArrayAdapter<String>(this,android.R.layout.simple_dropdown_item_1line,list);
    usersList.setAdapter(adapter);
    usersList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
            String s = usersList.getItemAtPosition(i).toString();
            Intent intent = new Intent(getApplicationContext(),Chat_Room.class);
            intent.putExtra("user_name",s);

            startActivity(intent);
        }
    });
    mDatabaseUser.addChildEventListener(new ChildEventListener() {
        @Override
        public void onChildAdded(DataSnapshot dataSnapshot, String s) {
            /*list.add((String) dataSnapshot.getValue(String.class));*/

            User user = dataSnapshot.getValue(User.class);

            // Check for null
            if (user == null) {
               // Log.e(TAG, "User data is null!");
                return;
            }
            list.add(user.username);

            adapter.notifyDataSetChanged();
        }

        @Override
        public void onChildChanged(DataSnapshot dataSnapshot, String s) {

        }

        @Override
        public void onChildRemoved(DataSnapshot dataSnapshot) {

        }

        @Override
        public void onChildMoved(DataSnapshot dataSnapshot, String s) {

        }

        @Override
        public void onCancelled(DatabaseError databaseError) {

        }
    });
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch(item.getItemId()) {
        case R.id.action_logout:
            FirebaseAuth.getInstance().signOut();
            startActivity(new Intent(this, SignActivity.class));
            finish();
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}
}

Chat_Room.java

  public class Chat_Room extends AppCompatActivity {
private static final String TAG = MainActivity.class.getName();

private EditText metText;
private Button mbtSent;
private DatabaseReference mFirebaseRef;

private List<Chat> mChats;
private RecyclerView mRecyclerView;
private ChatAdapter mAdapter;
private String mId;

@SuppressLint("HardwareIds")
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_chat__room);

    String user_name = getIntent().getStringExtra("user_name");
    setTitle(user_name);
    metText = (EditText) findViewById(R.id.etText);
    mbtSent = (Button) findViewById(R.id.btSent);
    mRecyclerView = (RecyclerView) findViewById(R.id.rvChat);
    mChats = new ArrayList<>();

    mId = Settings.Secure.getString(this.getContentResolver(), Settings.Secure.ANDROID_ID);
    mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
    //mRecyclerView.setItemAnimator(new SlideInOutLeftItemAnimator(mRecyclerView));
    mAdapter = new ChatAdapter(mChats, mId);
    mRecyclerView.setAdapter(mAdapter);

    /**
     * Firebase - Inicialize
     */
    FirebaseDatabase database = FirebaseDatabase.getInstance();
    mFirebaseRef = database.getReference("message");
    mbtSent.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            String message = metText.getText().toString();

            if (!message.isEmpty()) {
                /**
                 * Firebase - Send message
                 */
                mFirebaseRef.push().setValue(new Chat(message, mId));
            }

            metText.setText("");
        }
    });

    mFirebaseRef.addChildEventListener(new ChildEventListener() {
        @Override
        public void onChildAdded(DataSnapshot dataSnapshot, String s) {
            if (dataSnapshot != null && dataSnapshot.getValue() != null) {
                try {

                    Chat model = dataSnapshot.getValue(Chat.class);

                    mChats.add(model);
                    mRecyclerView.scrollToPosition(mChats.size() - 1);
                    mAdapter.notifyItemInserted(mChats.size() - 1);
                } catch (Exception ex) {
                    Log.e(TAG, ex.getMessage());
                }
            }
        }

        @Override
        public void onChildChanged(DataSnapshot dataSnapshot, String s) {

        }

        @Override
        public void onChildRemoved(DataSnapshot dataSnapshot) {

        }

        @Override
        public void onChildMoved(DataSnapshot dataSnapshot, String s) {

        }

        @Override
        public void onCancelled(DatabaseError databaseError) {
            Log.d(TAG, databaseError.getMessage());
        }
    });
}
}

Chat.java

   public class Chat {
public String message;
public String id;

public Chat() {
}

public Chat(String message, String id) {
    this.message = message;
    this.id = id;
}

public String getMessage() {
    return message;
}

public void setMessage(String message) {
    this.message = message;
}

public String getId() {
    return id;
}

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

ChatAdapter.java

    class ChatAdapter extends RecyclerView.Adapter<ChatAdapter.ViewHolder> {
private static final int CHAT_END = 1;
private static final int CHAT_START = 2;

private List<Chat> mDataSet;
private String mId;

ChatAdapter(List<Chat> dataSet, String id) {
    mDataSet = dataSet;
    mId = id;
}

@Override
public ChatAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View v;

    if (viewType == CHAT_END) {
        v = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item_chat_end, parent, false);
    } else {
        v = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_item_chat_start, parent, false);
    }

    return new ViewHolder(v);
}

@Override
public int getItemViewType(int position) {
    if (mDataSet.get(position).getId().equals(mId)) {
        return CHAT_END;
    }

    return CHAT_START;
}

@Override
public void onBindViewHolder(ViewHolder holder, int position) {
    Chat chat = mDataSet.get(position);
    holder.mTextView.setText(chat.getMessage());
}

@Override
public int getItemCount() {
    return mDataSet.size();
}

/**
 * Inner Class for a recycler view
 */
class ViewHolder extends RecyclerView.ViewHolder {
    TextView mTextView;

    ViewHolder(View v) {
        super(v);
        mTextView = (TextView) itemView.findViewById(R.id.tvMessage);
    }
}
}

如何改进这一点，以便在触摸每个用户时，它显示该用户的聊天消息与所有用户消息不同。

Image of database

一对一聊天Facilty

0 个答案: