向适配器添加新数据会影响初始值

public class messageadapter extends recyclerview.adapter<recyclerview.viewholder>。{

list<message>data=collections.emptylist();
list<integer>message_type=collections.emptylist();

//创建构造函数以初始化从MainActivity发送的上下文和数据
public messageadapter(列表<message>数据,列表<integer>消息类型){
this.data=数据;
this.message_type=message_type;
}

public void additem(message item,int message_type){

添加(项);
this.message_type.add(0,message_type);

}

//在创建视窗夹时展开布局
@覆盖
public recyclerview.viewholder oncreateviewholder(viewgroup viewgroup,int i){
开关(一){
案例0:
view v=layoutInflator.from(viewGroup.getContext()).inflat(r.layout.message_non_user,viewGroup,false);
返回新的视点0(v);
案例2:
view q=layoutInflator.from(viewGroup.getContext()).inflat(r.layout.message_user,viewGroup,false);
返回新的viewholder1(q);
}
view v=layoutInflator.from(viewGroup.getContext()).inflat(r.layout.message_non_user,viewGroup,false);
返回新的视窗保持器1(v);
}

//绑定数据
@覆盖
public void onbindViewholder(recyclerview.viewholder Viewholder,final int position){
开关(viewholder.getItemViewType()){
案例0:
viewholder0 viewholder0=(viewholder0)viewholder;
message current0=data.get(位置);
viewholder0.body.settext(current0.message);
断裂;

案例2:
viewholder1 viewholder1=(viewholder1)viewholder;
message current1=data.get(位置);
viewholder1.body.settext(当前1.message);
断裂;
}
}

//返回列表中的合计项
@覆盖
public int getItemCount()。{
返回data.size();
}

@覆盖
公共int GetItemViewType(int位置){
int temp=消息类型get(位置);
如果(温度==0){
返回0;
}
返回2;

}
类ViewHolder0扩展RecyclerView.ViewHolder{

文本查看正文;

公共视图保持器0(最终视图项视图){
super(项目视图);
body=(textview)itemview.findview byid(r.id.message_body);
}
}

类ViewHolder1扩展RecyclerView.ViewHolder{

文本查看正文;

公共视图保持器1(最终视图项视图){
super(项目视图);
body=(textview)itemview.findview byid(r.id.message_body);

}
}
}
然后这是用于发送消息操作的代码。

message user_input=new message();
user_input.message=chat_input.getText().toString();
messageadapter.additem(用户输入,0);

messageadapter.notifyItemInserted(messageadapter.getItemCount()+1);

messagesrecycleView.scrollToposition(messageadapter.getItemCount()-1);
messageadapter.notifyDataSetChanged();
chat_input.getText().clear();

感谢您的帮助:)MessageAdapter在客户机的设备上,所以它会出现在他们的屏幕上。

来自用户的消息是右对齐的,对于非用户则是右对齐的。

当用户发送消息时,与所有消息向上移动一个点相反,文本向上移动,但不是实际的消息对象。

我正在尝试让用户发送一条消息,所有以前的消息都有效地向上移动,以便新消息显示在下面。





最初,非用户消息是Hello但是在我发送用户的消息之后,非用户下面的消息,Hey取代它。

这是我的代码消息适配器:

public class MessageAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

List<Message> data= Collections.emptyList();
List<Integer> message_type= Collections.emptyList();

// create constructor to initialize context and data sent from MainActivity
public MessageAdapter(List<Message> data, List<Integer> message_type) {
    this.data=data;
    this.message_type=message_type;
}

public void addItem(Message item, int message_type){

    this.data.add(item);
    this.message_type.add(0, message_type);

}

// Inflate the layout when ViewHolder created
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
    switch (i) {
        case 0:
            View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.message_non_user, viewGroup, false);
            return new ViewHolder0(v);
        case 2:
            View q = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.message_user, viewGroup, false);
            return new ViewHolder1(q);
    }
    View v = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.message_non_user, viewGroup, false);
    return new ViewHolder1(v);
}

// Bind data
@Override
public void onBindViewHolder(RecyclerView.ViewHolder viewHolder, final int position) {
    switch (viewHolder.getItemViewType()) {
        case 0:
            ViewHolder0 viewHolder0 = (ViewHolder0)viewHolder;
            Message current0 = data.get(position);
            viewHolder0.body.setText(current0.message);
            break;

        case 2:
            ViewHolder1 viewHolder1 = (ViewHolder1)viewHolder;
            Message current1 = data.get(position);
            viewHolder1.body.setText(current1.message);
            break;
    }
}

// return total item from List
@Override
public int getItemCount() {
    return data.size();
}

@Override
public int getItemViewType(int position) {
    int temp = message_type.get(position);
    if(temp == 0 ){
        return 0;
    }
    return 2;

}
class ViewHolder0 extends RecyclerView.ViewHolder {

    TextView body;

    public ViewHolder0(final View itemView) {
        super(itemView);
        body = (TextView) itemView.findViewById(R.id.message_body);
    }
}

class ViewHolder1 extends RecyclerView.ViewHolder {

    TextView body;

    public ViewHolder1 (final View itemView) {
        super(itemView);
        body = (TextView) itemView.findViewById(R.id.message_body);

    }
}
}


这就是send-message action:

 Message user_input = new Message();
 user_input.message = chat_input.getText().toString();
 messageAdapter.addItem(user_input, 0);

 messageAdapter.notifyItemInserted(messageAdapter.getItemCount()+1);

 MessagesRecyclerview.scrollToPosition(messageAdapter.getItemCount() - 1);
 messageAdapter.notifyDataSetChanged();
 chat_input.getText().clear();


感谢您的帮助:)