android中RecyclerView控件实现长按弹出PopupMenu菜单功能

之前写过一篇文章:android中实现简单的聊天功能

现在是在之前功能的基础上,添加一个长按聊天记录,删除对应聊天记录的功能

RecyclerView控件,没有对应的长按事件,我们需要自己手工添加,修改对应的适配器类,注意红色内容为添加内容

ChatAdapter.java:

package com.example.chenrui.app1;

import android.support.annotation.NonNull;
import android.support.v7.widget.RecyclerView;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.LinearLayout;
import android.widget.TextView; import com.example.chenrui.common.Chat; import java.util.List; public class ChatAdapter extends RecyclerView.Adapter<ChatAdapter.ViewHolder> { private List<Chat> chatList; public ChatAdapter(List<Chat> chatList) {
this.chatList = chatList;
} @NonNull
@Override
public ViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.chat_item,viewGroup,false);
ViewHolder viewHolder = new ViewHolder(view);
return viewHolder;
} @Override
public void onBindViewHolder(@NonNull final ViewHolder viewHolder, final int i) {
Chat chat = chatList.get(i);
viewHolder.chatText.setText(chat.getContent());
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(viewHolder.chatText.getLayoutParams());
if(chat.getTargetUser().equals("张三")) {
params.gravity = Gravity.LEFT;
} else {
params.gravity = Gravity.RIGHT;
}
viewHolder.chatText.setLayoutParams(params); if(onItemClickListener!=null) {
viewHolder.itemView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
onItemClickListener.onItemLongClick(viewHolder.itemView,i);
return false;
}
});
}
} @Override
public int getItemCount() {
return chatList.size();
} static class ViewHolder extends RecyclerView.ViewHolder { TextView chatText; public ViewHolder(@NonNull View itemView) {
super(itemView); chatText = itemView.findViewById(R.id.chatText);
}
} private OnItemClickListener onItemClickListener;
public interface OnItemClickListener{
void onItemLongClick(View view , int pos);
} public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
this.onItemClickListener = onItemClickListener;
}
}

修改对应的类,注意红色内容为添加内容

这里实现了长按聊天内容,弹出一个PopupMenu菜单,PopupMenu菜单的使用参考我的上一篇文章:Android中创建PopupMenu弹出式菜单

菜单有一个删除功能,点击删除功能,删除对应的聊天记录

MainActivity.java

package com.example.chenrui.app1;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.MenuItem;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.PopupMenu;
import android.widget.Spinner; import com.example.chenrui.common.Chat; import java.util.ArrayList;
import java.util.List; public class MainActivity extends AppCompatActivity { @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main); final RecyclerView chatList = findViewById(R.id.chatList); final List<Chat> chatData = new ArrayList<Chat>();
final ChatAdapter chatAdapter = new ChatAdapter(chatData);
chatList.setAdapter(chatAdapter);
LinearLayoutManager layoutManager = new LinearLayoutManager(this);
chatList.setLayoutManager(layoutManager);
chatAdapter.setOnItemClickListener(new ChatAdapter.OnItemClickListener() {
@Override
public void onItemLongClick(View view, final int pos) {
PopupMenu popupMenu = new PopupMenu(MainActivity.this,view);
popupMenu.getMenuInflater().inflate(R.menu.menu3,popupMenu.getMenu()); //弹出式菜单的菜单项点击事件
popupMenu.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() { @Override
public boolean onMenuItemClick(MenuItem item) {
if(item.getItemId()==R.id.delete) {
chatData.remove(pos);
chatAdapter.notifyItemRemoved(pos);
}
return false;
}
});
popupMenu.show();
}
}); final Spinner targetUser = findViewById(R.id.targetUser);
String[] data = {"张三","李四"};
ArrayAdapter<String> adapter = new ArrayAdapter<String> (this,R.layout.support_simple_spinner_dropdown_item,data);
targetUser.setAdapter(adapter); final EditText chatContent = findViewById(R.id.chatContent); Button chatSubmit = findViewById(R.id.chatSubmit);
chatSubmit.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(!chatContent.getText().toString().equals("")) {
String user = targetUser.getSelectedItem().toString();
chatData.add(new Chat(user, chatContent.getText().toString())); chatAdapter.notifyItemInserted(chatData.size() - 1);
chatList.scrollToPosition(chatData.size() - 1);
chatContent.setText("");
}
}
});
}
}

显示效果:

android中RecyclerView控件实现长按弹出PopupMenu菜单功能

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