SwipeRefreshLayout
下拉刷新控件SwipeRefreshLayout,通过下拉刷新实现列表的刷新。
activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.fitsoft.MainActivity">
<android.support.v4.widget.SwipeRefreshLayout
android:id="@+id/swipe_refresh_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:id="@+id/my_list_view"
android:layout_width="match_parent"
android:layout_height="match_parent">
</ListView>
</android.support.v4.widget.SwipeRefreshLayout>
</android.support.constraint.ConstraintLayout>
在下拉刷新控件中添加了一个ListView列表控件。
MainActivity:
package com.fitsoft;
import android.graphics.Color;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends AppCompatActivity {
SwipeRefreshLayout swipeRefreshLayout;
ListView listView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
swipeRefreshLayout = findViewById(R.id.swipe_refresh_layout);
listView = findViewById(R.id.my_list_view);
final List<String> list = new ArrayList<>();
for(int i=0; i<30; i++){
list.add(i+"");
}
final ArrayAdapter<String> adapter = new ArrayAdapter<>(this,
android.R.layout.simple_list_item_1,
android.R.id.text1, list);
listView.setAdapter(adapter);
swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
@Override
public void onRefresh() {
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
swipeRefreshLayout.setRefreshing(false);
Toast.makeText(MainActivity.this, "加载完成!", Toast.LENGTH_SHORT).show();
for(int i=0; i<20; i++){
list.add("新加的数据:"+i);
}
adapter.notifyDataSetChanged();
}
}, 2000);
}
});
//循环一圈颜色
swipeRefreshLayout.setColorSchemeColors(Color.RED, Color.GREEN, Color.BLUE, Color.CYAN);
//下拉高度
swipeRefreshLayout.setProgressViewOffset(false, 200, 500);
}
}
这里首先为ListView绑定适配器,并且设置数据源,数据源就是0-29的字符串。
这里将变量定义为final,为什么呢?
https://blog.csdn.net/tianjindong0804/article/details/81710268
这个博主解释的很好,我很赞同(小声BB),然后在swipeRefreshLayout的下拉刷新方法中开启一个2秒的定时器,2秒后:
swipeRefreshLayout.setRefreshing(false);
将刷新的图标关闭,并且在原来的数据源的基础上新加了20条数据。
这里高度设置有点大,有点丑,凑合看吧(不然你也没招对不对=_=)
效果图:
(图片被loli删除)