在弄android刷新的时候,可算是耗费了一番功夫,最后发觉有现成的控件,并且非常好用,这里记录一下。
原文是 https://blog.csdn.net/huangxin112/article/details/78781682 ,这里是看了之后,结合自己实际遇到的问题写的。
首先引入包。
//下拉框
implementation ‘com.android.support:recyclerview-v7:28.0.0-beta01‘
implementation ‘com.scwang.smartrefresh:SmartRefreshLayout:1.0.3‘
implementation ‘com.scwang.smartrefresh:SmartRefreshHeader:1.0.3‘//没有使用特殊Header,可以不加这行
recyclerview 是为了数据显示用,因为在使用中,发现 使用ListView 会报错,不过我看别人用成功了的,具体我也懒得去查了。
recyclerview 以后具体在学习吧,反正是个比较好用的东西就是了。
首先是页面文件 activity_main.xml
<com.scwang.smartrefresh.layout.SmartRefreshLayout 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:id="@+id/refreshLayout" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".MainActivity" > <android.support.v7.widget.RecyclerView android:id="@+id/recyclerview" android:layout_width="match_parent" android:layout_height="match_parent" android:overScrollMode="never" android:background="#fff" /> </com.scwang.smartrefresh.layout.SmartRefreshLayout>
接着是具体的布局显示文件: item.xml
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="horizontal" android:layout_width="match_parent" android:layout_height="60dp" android:gravity="center"> <ImageView android:id="@+id/iv_image" android:layout_width="60dp" android:layout_height="60dp" android:gravity="center" android:background="@mipmap/ic_launcher"></ImageView> <LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <TextView android:id="@+id/tv_title" android:layout_width="match_parent" android:layout_height="30dp" android:text="title" android:gravity="center" ></TextView> <TextView android:id="@+id/tv_content" android:layout_width="match_parent" android:layout_height="30dp" android:text="content1231231231232323" android:gravity="center" ></TextView> </LinearLayout> </LinearLayout>
显示的bean 对象,
package com.example.administrator.shuaxin;
public class ItemBean {
int itemImage;
String itemTitle;
String itemContent;
public ItemBean(int itemImage , String itemTitle, String itemContent) {
this.itemTitle = itemTitle;
this.itemContent = itemContent;
this.itemImage = itemImage;
}
}
适配器MyAdapter:
package com.example.administrator.shuaxin;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import java.util.List;
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder>{
private List<ItemBean> mList;
static class ViewHolder extends RecyclerView.ViewHolder{
View myView;
ImageView imageView;
TextView title;
TextView content;
public ViewHolder(View itemView) {
super(itemView);
myView = itemView;
imageView = (ImageView) itemView.findViewById(R.id.iv_image);
title = (TextView) itemView.findViewById(R.id.tv_title);
content = (TextView) itemView.findViewById(R.id.tv_content);
}
}
public MyAdapter(List<ItemBean> list){
this.mList = list;
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item,null);
final ViewHolder holder = new ViewHolder(view);
return holder;
}
//将数据绑定到控件上
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
ItemBean bean = mList.get(position);
holder.imageView.setBackgroundResource(bean.itemImage);
holder.title.setText(bean.itemTitle);
holder.content.setText(bean.itemContent);
}
@Override
public int getItemCount() {
return mList.size();
}
//下面两个方法提供给页面刷新和加载时调用
public void add(List<ItemBean> addMessageList) {
//增加数据
int position = mList.size();
mList.addAll(position, addMessageList);
notifyItemInserted(position);
}
public void refresh(List<ItemBean> newList) {
//刷新数据
mList.removeAll(mList);
mList.addAll(newList);
notifyDataSetChanged();
}
}
然后是Activity文件。
package com.example.administrator.shuaxin;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import com.scwang.smartrefresh.header.MaterialHeader;
import com.scwang.smartrefresh.layout.api.RefreshLayout;
import com.scwang.smartrefresh.layout.footer.ClassicsFooter;
import com.scwang.smartrefresh.layout.header.ClassicsHeader;
import com.scwang.smartrefresh.layout.listener.OnLoadmoreListener;
import com.scwang.smartrefresh.layout.listener.OnRefreshListener;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
public class MainActivity extends AppCompatActivity {
private List<ItemBean> list;
private MyAdapter myAdapter;
private RecyclerView recyclerView;
RefreshLayout refreshLayout;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
refreshLayout = (RefreshLayout)findViewById(R.id.refreshLayout);
//初始数据加载
initDate();
//刷新数据加载
setPullRefresher();
}
private void initDate(){
list = new ArrayList<ItemBean>();
for (int i=0;i<20;i++){
list.add(new ItemBean(
R.mipmap.ic_launcher,
"initTitle"+i,
new Date().toString()+""
));
}
myAdapter = new MyAdapter(list);
recyclerView = (RecyclerView) findViewById(R.id.recyclerview);
LinearLayoutManager layoutManager = new LinearLayoutManager(this);//纵向线性布局
recyclerView.setLayoutManager(layoutManager);
recyclerView.setAdapter(myAdapter);
}
private void setPullRefresher(){
//设置 Header 为 MaterialHeader
//设置 Header 为 ClassicsFooter 比较经典的样式
refreshLayout.setRefreshHeader(new ClassicsHeader(this));
//设置 Footer 为 经典样式
refreshLayout.setRefreshFooter(new ClassicsFooter(this));
refreshLayout.setOnRefreshListener(new OnRefreshListener() {
@Override
public void onRefresh(RefreshLayout refreshlayout) {
//在这里执行上拉刷新时的具体操作(网络请求、更新UI等)
//模拟网络请求到的数据
ArrayList<ItemBean> newList = new ArrayList<ItemBean>();
for (int i=0;i<20;i++){
newList.add(new ItemBean(
R.mipmap.ic_launcher,
"newTitle"+i,
new Date().toString()+""
));
}
myAdapter.refresh(newList);
refreshlayout.finishRefresh(2000/*,false*/);
//不传时间则立即停止刷新 传入false表示刷新失败
}
});
refreshLayout.setOnLoadmoreListener(new OnLoadmoreListener() {
@Override
public void onLoadmore(RefreshLayout refreshlayout) {
//模拟网络请求到的数据
ArrayList<ItemBean> newList = new ArrayList<ItemBean>();
for (int i=0;i<20;i++){
newList.add(new ItemBean(
R.mipmap.ic_launcher,
"addTitle"+i,
new Date().toString()+""
));
}
myAdapter.add(newList);
//在这里执行下拉加载时的具体操作(网络请求、更新UI等)
refreshlayout.finishLoadmore(2000/*,false*/);//不传时间则立即停止刷新 传入false表示加载失败
}
});
}
}
看下效果。