概述
谷歌官方推出了SwipeRefreshLayout 来实现下拉刷新的效果。对比以前我们常用的 pull-to-refesh ,这个方案显得更加的简单方便。
关联项目引用(管理依赖)
在你的 应用级别的 build.gradle 中添加如下:
compile ‘com.android.support:appcompat-v7:23.0.0‘ compile ‘com.android.support:support-v4:23.0.0‘
编写布局(Layout)
<LinearLayout 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" android:orientation="vertical" tools:context=".MainActivity"> <android.support.v4.widget.SwipeRefreshLayout android:id="@+id/swipeRefreshLayout1" android:layout_width="match_parent" android:layout_height="match_parent"> <ListView android:id="@+id/listview1" android:layout_width="match_parent" android:layout_height="match_parent" /> </android.support.v4.widget.SwipeRefreshLayout> </LinearLayout>
在代码中 添加监听器处理事件
public void setOnRefreshListener(OnRefreshListener listener)
完整代码
package demo.vir56k.swiperefreshlayoutdemo; import android.os.Handler; import android.support.v4.widget.SwipeRefreshLayout; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.Menu; import android.view.MenuItem; import android.widget.ArrayAdapter; import android.widget.ListView; import java.util.ArrayList; import java.util.Arrays; import java.util.List; public class MainActivity extends AppCompatActivity { private static final int REFRESH_COMPLETE = 0X110; private SwipeRefreshLayout mSwipeLayout; private ListView mListView; private ArrayAdapter<String> mAdapter; private List<String> mDatas; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mListView = (ListView) findViewById(R.id.listview1); mSwipeLayout = (SwipeRefreshLayout) findViewById(R.id.swipeRefreshLayout1); mDatas = creatDataSource(); mSwipeLayout.setOnRefreshListener(mSwipeRefreshLayoutOnRefreshListener); mSwipeLayout.setColorSchemeResources(android.R.color.holo_blue_bright, android.R.color.holo_green_light, android.R.color.holo_orange_light, android.R.color.holo_red_light); mAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, mDatas); mListView.setAdapter(mAdapter); } private List<String> creatDataSource() { mDatas = new ArrayList<String>(); for (int i = 0; i < 5; i++) { mDatas.add("item" + i); } return mDatas; } SwipeRefreshLayout.OnRefreshListener mSwipeRefreshLayoutOnRefreshListener = new SwipeRefreshLayout.OnRefreshListener() { @Override public void onRefresh() { mHandler.sendEmptyMessageDelayed(REFRESH_COMPLETE, 2000); } }; private Handler mHandler = new Handler() { public void handleMessage(android.os.Message msg) { switch (msg.what) { case REFRESH_COMPLETE: List<String> lst = new ArrayList<String>(); for (int i = mDatas.size() + 3; i > mDatas.size(); i--) { lst.add("item -" + i); } mDatas.addAll(0, lst); mAdapter.notifyDataSetChanged(); mSwipeLayout.setRefreshing(false); break; } } ; }; }
至此完成。
补充:
其他情形,遇到"SwipeRefreshLayout 的子控件不 直接是个listview 等,是个普通 relativewlayout 怎么办?"
解决方法: 继承 SwipeRefreshLayout 重写 canChildScrollUp 方法
/* * Copyright 2016, The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.example.android.architecture.blueprints.todoapp.tasks; import android.content.Context; import android.support.v4.view.ViewCompat; import android.support.v4.widget.SwipeRefreshLayout; import android.util.AttributeSet; import android.view.View; /** * Extends {@link SwipeRefreshLayout} to support non-direct descendant scrolling views. * <p> * {@link SwipeRefreshLayout} works as expected when a scroll view is a direct child: it triggers * the refresh only when the view is on top. This class adds a way (@link #setScrollUpChild} to * define which view controls this behavior. */ public class ScrollChildSwipeRefreshLayout extends SwipeRefreshLayout { private View mScrollUpChild; public ScrollChildSwipeRefreshLayout(Context context) { super(context); } public ScrollChildSwipeRefreshLayout(Context context, AttributeSet attrs) { super(context, attrs); } @Override public boolean canChildScrollUp() { if (mScrollUpChild != null) { return ViewCompat.canScrollVertically(mScrollUpChild, -1); } return super.canChildScrollUp(); } public void setScrollUpChild(View view) { mScrollUpChild = view; } }
时间: 2024-10-31 01:06:14