GridView的簡單使用

項目GitHub地址：https://github.com/leonInShanghai/IMbobo   

GridView XML佈局:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".controller.activity.GroupDetailActivity">

    <com.hyphenate.easeui.widget.EaseTitleBar
        app:titleBarTitle = "群详情"
        android:layout_width = "match_parent"
        android:layout_height = "wrap_content" />

    <GridView
        android:id="@+id/gv_groupdetail"
        android:numColumns="4"
        android:horizontalSpacing="10dp"
        android:verticalSpacing="10dp"
        android:layout_width="match_parent"
        android:layout_weight="1"
        android:layout_height="0dp">
    </GridView>

    <Button
        android:id="@+id/bt_groupdetail_out"
        android:background="@android:color/holo_red_light"
        android:textColor="@android:color/white"
        android:text="退群"
        android:textSize="20sp"
        android:layout_width="match_parent"
        android:layout_height="60dp" />

</LinearLayout>


Activity 類:

package com.example.administrator.imbobo.controller.activity;


import android.app.Activity;
import android.content.Intent;
import android.support.v4.content.LocalBroadcastManager;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.GridView;
import android.widget.Toast;
import com.example.administrator.imbobo.controller.adapter.GroupDetailAdapte;
import com.example.administrator.imbobo.R;
import com.example.administrator.imbobo.model.Model;
import com.example.administrator.imbobo.model.bean.UserInfo;
import com.example.administrator.imbobo.utils.Constant;
import com.hyphenate.chat.EMClient;
import com.hyphenate.chat.EMGroup;
import com.hyphenate.exceptions.HyphenateException;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by Leon on 2018/11/24
 * Functions: 群详情页面
 */
public class GroupDetailActivity extends Activity {

    /**网格视图*/
    private GridView gv_groupdetail;

    /**退群的按钮*/
    private Button bt_groupdetail_out;

    /**群组类（环信easeUI定义的类*/
    private EMGroup mGroup;

    //群成員集合
    private List<UserInfo> mUsers;

    /**GridView 適配器*/
    private GroupDetailAdapte groupDetailAdapte;


    /**處理 增加 和刪除群成員的業務邏輯的接口*/
    private GroupDetailAdapte.OnGroupDetailListener mOnGroupDetailListener = new GroupDetailAdapte.
            OnGroupDetailListener() {
        @Override
        public void onAddMembers() {
            //添加群成員-開闢子綫程做網絡請求

        }

        @Override
        public void onDeleteMember(UserInfo user) {
            //刪除群成員-開闢子綫程做網絡請求
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_grour_detail);

        initView();

        /**获取传递过来的环信id*/
        getData();

        initData();
    }

    private void initData(){
        //初始化button显示
        initButtonDisplay();

        //初始化gridview
        initGridView();

        //從環信服務器獲取所有的群成員
        getMembersFromHxServer();
    }

    /**從環信服務器獲取所有的群成員*/
    private void getMembersFromHxServer(){
        //開闢子綫程做網絡請求
        Model.getInstance().getGloabalThreadPool().execute(new Runnable() {
            @Override
            public void run() {
                try {
                   //從環信服務器獲取所有的群成員信息
                   EMGroup emGroup = EMClient.getInstance().groupManager().getGroupFromServer(mGroup.getGroupId());
                   List<String> menbers = emGroup.getMembers();

                   if (menbers != null && menbers.size() >= 0){

                       mUsers = new ArrayList<>();

                       //轉換
                       for (String menber : menbers){
                           UserInfo userInfo = new UserInfo(menber);
                           mUsers.add(userInfo);
                       }
                   }

                   //更新頁面-回到主綫程
                   runOnUiThread(new Runnable() {
                       @Override
                       public void run() {
                           //刷新適配器
                           groupDetailAdapte.refresh(mUsers);
                       }
                   });
                } catch (final HyphenateException e) {
                    e.printStackTrace();
                    //更新頁面-回到主綫程
                    runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                           Toast.makeText(GroupDetailActivity.this,"獲取群信息失敗"+e.toString(),
                                   Toast.LENGTH_SHORT).show();
                        }
                    });
                }
            }
        });
    }

    //初始化gridview
    private void initGridView(){

        /**
         *  群主有邀請人入群的權限
         *  另外當 群組是公開的時候群成員也有邀請人的權限
         */
        boolean isCanModify = EMClient.getInstance().getCurrentUser().equals(mGroup.getOwner()) ||
                mGroup.isPublic();

        /**
         * 第一個參數是上下文
         * 第二個參數是標記 是 群主/群員
         */
        groupDetailAdapte = new GroupDetailAdapte(this,isCanModify,
                mOnGroupDetailListener);

        //GridView 設置 adapte
        gv_groupdetail.setAdapter(groupDetailAdapte);
    }

    //初始化button显示 - 退群/解散群
    private void initButtonDisplay(){

        //判断当前用户是否为群组
        if (EMClient.getInstance().getCurrentUser().equals(mGroup.getOwner())){//群主
            bt_groupdetail_out.setText("解散群");

            bt_groupdetail_out.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {

                    //开辟子线程-去环信服务器解散群
                    Model.getInstance().getGloabalThreadPool().execute(new Runnable() {
                        @Override
                        public void run() {
                            try {
                                //去环信服务器解散群
                                EMClient.getInstance().groupManager().destroyGroup(mGroup.getGroupId());

                                //发送一个退群的广播
                                exitGroupBroatCast();

                                //更新页面
                                runOnUiThread(new Runnable() {
                                    @Override
                                    public void run() {
                                        Toast.makeText(GroupDetailActivity.this,"解散群成功",
                                                Toast.LENGTH_SHORT).show();

                                        //结束当前页面
                                        finish();
                                    }
                                });

                            } catch (final HyphenateException e) {
                                e.printStackTrace();
                                //更新页面
                                runOnUiThread(new Runnable() {
                                    @Override
                                    public void run() {
                                        Toast.makeText(GroupDetailActivity.this,"解散群失败"+e.toString(),
                                                Toast.LENGTH_SHORT).show();
                                    }
                                });
                            }
                        }
                    });
                }
            });

        }else {//群成员
            bt_groupdetail_out.setText("退群");

            bt_groupdetail_out.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    //开辟子线程做服务器请求操作
                    Model.getInstance().getGloabalThreadPool().execute(new Runnable() {
                        @Override
                        public void run() {
                            try {
                                //告诉环信服务器群成员要退群
                                EMClient.getInstance().groupManager().leaveGroup(mGroup.getGroupId());

                                //发送一个退群的广播
                                exitGroupBroatCast();

                                //更新页面
                                runOnUiThread(new Runnable() {
                                    @Override
                                    public void run() {
                                        Toast.makeText(GroupDetailActivity.this,"退群成功",
                                                Toast.LENGTH_SHORT).show();

                                        //结束当前页面
                                        finish();
                                    }
                                });
                            } catch (final HyphenateException e) {
                                e.printStackTrace();
                                //更新页面
                                runOnUiThread(new Runnable() {
                                    @Override
                                    public void run() {
                                        Toast.makeText(GroupDetailActivity.this,"退群失败"+e.toString(),
                                                Toast.LENGTH_SHORT).show();
                                    }
                                });
                            }
                        }
                    });
                }
            });
        }
    }

    /**发送退群和解散群广播*/
    private void  exitGroupBroatCast(){
        LocalBroadcastManager mLBM = LocalBroadcastManager.getInstance(GroupDetailActivity.this);

        Intent intent = new Intent(Constant.EXIT_GROUP);

        intent.putExtra(Constant.GROUP_ID,mGroup.getGroupId());

        mLBM.sendBroadcast(intent);
    }

    /**获取传递过来的数据最终得到一个 mGroup*/
    private void getData(){
       String groupId = getIntent().getStringExtra(Constant.GROUP_ID);

       if (groupId == null){
           return;
       }else {
           mGroup = EMClient.getInstance().groupManager().getGroup(groupId);
       }
    }

    private void initView(){
        gv_groupdetail = (GridView)findViewById(R.id.gv_groupdetail);
        bt_groupdetail_out = (Button)findViewById(R.id.bt_groupdetail_out);
    }
}

適配器：

package com.example.administrator.imbobo.controller.adapter;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

import com.example.administrator.imbobo.R;
import com.example.administrator.imbobo.model.bean.UserInfo;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by Leon on 2018/11/25.
 * Functions: GroupDetailActivity 中的 GridView 的適配器
 */
public class GroupDetailAdapte extends BaseAdapter {

    private Context mContext;

    /*是否允許添加和刪除群成員*/
    private boolean mIsCanModify;

    /**GridView 的數據源*/
    private List<UserInfo> mUsers = new ArrayList<>();

    /**刪除模式 true：表示可以刪除 false：表示不可以刪除*/
    private boolean mIsDeleteModle;

    /**自定義接口 實現添加群成員和 刪除群成員的業務邏輯*/
    private OnGroupDetailListener mOnGroupDetailListener;

    public GroupDetailAdapte(Context context,boolean isCanModify,OnGroupDetailListener onGroupDetailListener) {
            this.mContext = context;
            this.mIsCanModify = isCanModify;
            this.mOnGroupDetailListener = onGroupDetailListener;
    }

    //刷新方法-用於刷新和傳參
    public void refresh(List<UserInfo> users){
        if (users != null && users.size() >= 0){
            //1.清空原有的數據
            mUsers.clear();

            //2.添加加號和減號
            initUsers();

            //3.添加數據 - index：0 是爲了把加號 減號 都擠到後面
            mUsers.addAll(0,users);
        }

        //刷新頁面
        notifyDataSetChanged();
    }

    //添加加號和減號
    private void initUsers(){
        UserInfo add = new UserInfo("add");
        UserInfo delete = new UserInfo("delete");

        //添加 加號 和 減號讓它們在數組集合的後邊
        mUsers.add(delete);
        mUsers.add(0,add);
    }

    @Override
    public int getCount() {
        return mUsers == null ? 0 : mUsers.size();
    }

    @Override
    public Object getItem(int position) {
        return mUsers.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        //1.獲取或創建ViewHolder
        ViewHolder holder = null;

        if (convertView == null){
            holder = new ViewHolder();

            convertView = View.inflate(mContext, R.layout.item_groupdetail,null);

            holder.photo = (ImageView) convertView.findViewById(R.id.iv_group_detail_photo);
            holder.delete = (ImageView)convertView.findViewById(R.id.iv_group_detatil_delete);
            holder.name = (TextView)convertView.findViewById(R.id.tv_group_detail_name);

            convertView.setTag(holder);
        }else{
            holder = (ViewHolder) convertView.getTag();
        }

        //2.獲取當前item數據
        final UserInfo userInfo = mUsers.get(position);

        //3.顯示數據
        if (mIsCanModify){//群主 或 公開群權限裏的群成員
            //佈局的處理
            if (position == getCount() - 1){//減號的位置特殊處理
                //刪除模式判斷
                if (mIsDeleteModle){
                    convertView.setVisibility(View.GONE);
                }else {
                    convertView.setVisibility(View.VISIBLE);

                    holder.photo.setImageResource(R.drawable.em_smiley_minus_btn);
                    holder.delete.setVisibility(View.GONE);
                    holder.name.setVisibility(View.INVISIBLE);
                }
            }else if (position == getCount() -2){//加號的位置特殊處理
                //刪除模式判斷（增刪模式）
                if (mIsDeleteModle){
                    convertView.setVisibility(View.GONE);
                }else {
                    convertView.setVisibility(View.VISIBLE);

                    holder.photo.setImageResource(R.drawable.em_smiley_add_btn);
                    holder.delete.setVisibility(View.GONE);
                    holder.name.setVisibility(View.INVISIBLE);
                }
            }else {//群成員
                convertView.setVisibility(View.VISIBLE);
                holder.name.setVisibility(View.VISIBLE);

                //名稱 由於我這裏昵稱是手機號太長，所以只顯示后四位
                if (userInfo.getName() != null){
                    String name = userInfo.getName().substring(userInfo.getName().length()-4,userInfo.getName().length());
                    holder.name.setText(name);
                }
                holder.photo.setImageResource(R.drawable.em_default_avatar);

                if (mIsDeleteModle){//刪除（增刪）模式
                    holder.delete.setVisibility(View.VISIBLE);
                }else {//非 刪除（增刪）模式
                    holder.delete.setVisibility(View.GONE);
                }
            }

            //點擊事件的處理
            if (position == getCount() - 1){//減號的位置
                holder.photo.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        if (!mIsDeleteModle){
                            mIsDeleteModle = true;
                            notifyDataSetChanged();
                        }
                    }
                });
            }else if (position == getCount() - 2){//加號的位置
                holder.photo.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        mOnGroupDetailListener.onAddMembers();
                    }
                });

            }else {//群成員的位置 delete 點擊事件的處理
             holder.delete.setOnClickListener(new View.OnClickListener() {
                 @Override
                 public void onClick(View v) {
                    mOnGroupDetailListener.onDeleteMember(userInfo);
                 }
             });
            }
        }else{//普通的群成員
            if (position == getCount() - 1 || position == getCount() - 2){//減號和加號的位置隱藏掉
                convertView.setVisibility(View.GONE);
            }else{
                convertView.setVisibility(View.VISIBLE);

                //名稱 由於我這裏昵稱是手機號太長，所以只顯示后四位
                if (userInfo.getName() != null){
                    String name = userInfo.getName().substring(userInfo.getName().length()-4,userInfo.getName().length());
                    holder.name.setText(name);
                }

                //頭像
                holder.photo.setImageResource(R.drawable.em_default_avatar);

                //刪除按鈕 - 普通成員沒有權力刪除和邀請群成員
                holder.delete.setVisibility(View.GONE);
            }
        }

        //4.返回View
        return convertView;
    }

    /**内部類 ViewHolder*/
    private class ViewHolder{
        private ImageView photo;
        private ImageView delete;
        private TextView name;
    }

    /**自定義接口 誰實現誰處理 刪除群成員 和添加群成員的業務邏輯*/
    public interface OnGroupDetailListener{
        /**添加群成員方法*/
        void onAddMembers();

        /**刪除群成員方法*/
        void onDeleteMember(UserInfo user);
    }
}