使用谷歌提供的SwipeRefreshLayout下拉控件,并自定义实现下拉加载的功能

package com.loaderman.swiperefreshdemo;

import android.os.Bundle;
import android.os.Handler;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import com.loaderman.swiperefreshdemo.view.SwipeRefreshView;

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


/**
 * 使用谷歌提供的SwipeRefreshLayout下拉控件进行下拉刷新
 */
public class MainActivity extends AppCompatActivity {
    private List<String> mList;
    private int mCount;
    private StringAdapter mAdapter;

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

        final SwipeRefreshView swipeRefreshView = (SwipeRefreshView) findViewById(R.id.srl);
        ListView listView = (ListView) findViewById(R.id.lv);

        // 设置适配器数据
        mList = new ArrayList<>();
        for (int i = 0; i < 30; i++) {
            mList.add("我是天才" + i + "号");
            mCount++;
        }
        mAdapter = new StringAdapter();
        listView.setAdapter(mAdapter);


        // 不能在onCreate中设置,这个表示当前是刷新状态,如果一进来就是刷新状态,SwipeRefreshLayout会屏蔽掉下拉事件
        //swipeRefreshLayout.setRefreshing(true);

        // 设置颜色属性的时候一定要注意是引用了资源文件还是直接设置16进制的颜色,因为都是int值容易搞混
        // 设置下拉进度的背景颜色,默认就是白色的
        swipeRefreshView.setProgressBackgroundColorSchemeResource(android.R.color.white);
        // 设置下拉进度的主题颜色
        swipeRefreshView.setColorSchemeResources(R.color.colorAccent, R.color.colorPrimary, R.color.colorPrimaryDark);

        // 下拉时触发SwipeRefreshLayout的下拉动画,动画完毕之后就会回调这个方法
        swipeRefreshView.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {

                // 开始刷新,设置当前为刷新状态
                //swipeRefreshLayout.setRefreshing(true);

                // 这里是主线程
                // 一些比较耗时的操作,比如联网获取数据,需要放到子线程去执行
                // TODO 获取数据
                final Random random = new Random();
                new Handler().postDelayed(new Runnable() {
                    @Override
                    public void run() {
                        mList.add(0, "我是天才" + random.nextInt(100) + "号");
                        mAdapter.notifyDataSetChanged();

                        Toast.makeText(MainActivity.this, "刷新了一条数据", Toast.LENGTH_SHORT).show();

                        // 加载完数据设置为不刷新状态,将下拉进度收起来
                        swipeRefreshView.setRefreshing(false);
                    }
                }, 1200);

                // System.out.println(Thread.currentThread().getName());

                // 这个不能写在外边,不然会直接收起来
                //swipeRefreshLayout.setRefreshing(false);
            }
        });


        // 设置下拉加载更多
        swipeRefreshView.setOnLoadListener(new SwipeRefreshView.OnLoadListener() {
            @Override
            public void onLoad() {
                new Handler().postDelayed(new Runnable() {
                    @Override
                    public void run() {

                        // 添加数据
                        for (int i = 30; i < 35; i++) {
                            mList.add("我是天才" + i+ "号");
                            // 这里要放在里面刷新,放在外面会导致刷新的进度条卡住
                            mAdapter.notifyDataSetChanged();
                        }

                        Toast.makeText(MainActivity.this, "加载了" + 5 + "条数据", Toast.LENGTH_SHORT).show();

                        // 加载完数据设置为不加载状态,将加载进度收起来
                        swipeRefreshView.setLoading(false);
                    }
                }, 1200);
            }
        });


    }


    /**
     * 适配器
     */
    private class StringAdapter extends BaseAdapter {

        @Override
        public int getCount() {
            return mList.size();
        }

        @Override
        public Object getItem(int position) {
            return mList.get(position);
        }
        @Override
        public long getItemId(int position) {
            return position;
        }
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            if (convertView == null) {
                convertView = View.inflate(MainActivity.this, android.R.layout.simple_list_item_1, null);
            }
            TextView tv = (TextView) convertView;
            tv.setGravity(Gravity.CENTER);
            tv.setPadding(0, 20, 0, 20);
            tv.setText(mList.get(position));

            return convertView;
        }
    }
}

 

package com.loaderman.swiperefreshdemo.view;

import android.content.Context;
import android.support.v4.widget.SwipeRefreshLayout;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;
import android.widget.AbsListView;
import android.widget.ListView;
import com.loaderman.swiperefreshdemo.R;

/**
 * 自定义View继承SwipeRefreshLayout,添加上拉加载更多的布局属性
 * Created by Pinger on 2016/9/26.
 */

public class SwipeRefreshView extends SwipeRefreshLayout {

    private final int mScaledTouchSlop;
    private final View mFooterView;
    private ListView mListView;
    private OnLoadListener mOnLoadListener;
    /**
     * 正在加载状态
     */
    private boolean isLoading;
    public SwipeRefreshView(Context context, AttributeSet attrs) {
        super(context, attrs);
        // 填充底部加载布局
        mFooterView = View.inflate(context, R.layout.view_footer, null);
        // 表示控件移动的最小距离,手移动的距离大于这个距离才能拖动控件
        mScaledTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();
        System.out.println("====" + mScaledTouchSlop);
    }
    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);
        // 获取ListView,设置ListView的布局位置
        if (mListView == null) {
            // 判断容器有多少个孩子
            if (getChildCount() > 0) {
                // 判断第一个孩子是不是ListView
                if (getChildAt(0) instanceof ListView) {
                    // 创建ListView对象
                    mListView = (ListView) getChildAt(0);

                    // 设置ListView的滑动监听
                    setListViewOnScroll();
                }
            }
        }
    }
    /**
     * 在分发事件的时候处理子控件的触摸事件
     *
     * @param ev
     * @return
     */
    private float mDownY, mUpY;
    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        switch (ev.getAction()) {
            case MotionEvent.ACTION_DOWN:
                // 移动的起点
                mDownY = ev.getY();
                break;
            case MotionEvent.ACTION_MOVE:
                // 移动过程中判断时候能下拉加载更多
                if (canLoadMore()) {
                    // 加载数据
                    loadData();
                }
                break;
            case MotionEvent.ACTION_UP:
                // 移动的终点
                mUpY = getY();
                break;
        }
        return super.dispatchTouchEvent(ev);
    }
    /**
     * 判断是否满足加载更多条件
     *
     * @return
     */
    private boolean canLoadMore() {
        // 1. 是上拉状态
        boolean condition1 = (mDownY - mUpY) >= mScaledTouchSlop;
        if (condition1) {
            System.out.println("是上拉状态");
        }

        // 2. 当前页面可见的item是最后一个条目
        boolean condition2 = false;
        if (mListView != null && mListView.getAdapter() != null) {
            condition2 = mListView.getLastVisiblePosition() == (mListView.getAdapter().getCount() - 1);
        }

        if (condition2) {
            System.out.println("是最后一个条目");
        }
        // 3. 正在加载状态
        boolean condition3 = !isLoading;
        if (condition3) {
            System.out.println("不是正在加载状态");
        }
        return condition1 && condition2 && condition3;
    }
    /**
     * 处理加载数据的逻辑
     */
    private void loadData() {
        System.out.println("加载数据...");
        if (mOnLoadListener != null) {
            // 设置加载状态,让布局显示出来
            setLoading(true);
            mOnLoadListener.onLoad();
        }

    }

    /**
     * 设置加载状态,是否加载传入boolean值进行判断
     *
     * @param loading
     */
    public void setLoading(boolean loading) {
        // 修改当前的状态
        isLoading = loading;
        if (isLoading) {
            // 显示布局
            mListView.addFooterView(mFooterView);
        } else {
            // 隐藏布局
           // mListView.removeFooterView(mFooterView);
            // 重置滑动的坐标
            mDownY = 0;
            mUpY = 0;
        }
    }

    /**
     * 设置ListView的滑动监听
     */
    private void setListViewOnScroll() {

        mListView.setOnScrollListener(new AbsListView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(AbsListView view, int scrollState) {
                // 移动过程中判断时候能下拉加载更多
                if (canLoadMore()) {
                    // 加载数据
                    loadData();
                }
            }
            @Override
            public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
            }
        });
    }

    /**
     * 上拉加载的接口回调
     */
    public interface OnLoadListener {
        void onLoad();
    }
    public void setOnLoadListener(OnLoadListener listener) {
        this.mOnLoadListener = listener;
    }
}

 activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.pinger.swiperefreshdemo.MainActivity">
    <!--使用谷歌官方的下拉刷新组件,只有下拉刷新功能-->
<!--
    <android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/srl"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <ListView
            android:id="@+id/lv"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>
    </android.support.v4.widget.SwipeRefreshLayout>
-->


    <!--自定义View实现SwipeRefreshLayout,添加上拉加载更多的功能-->
    <com.loaderman.swiperefreshdemo.view.SwipeRefreshView
        android:id="@+id/srl"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <ListView
            android:id="@+id/lv"
            android:layout_width="match_parent"
            android:layout_height="match_parent"/>
    </com.loaderman.swiperefreshdemo.view.SwipeRefreshView>
</RelativeLayout>

 view-footer.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
                android:layout_width="match_parent"
                android:layout_height="match_parent">
    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="50dp">
        <ProgressBar
            android:id="@+id/load_progress"
            android:layout_width="25dp"
            android:layout_height="25dp"
            android:layout_centerVertical="true"
            android:layout_marginLeft="30dp"/>
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:text="正在努力加载中..."
            android:textColor="@android:color/holo_red_dark"
            android:textSize="16sp"/>
    </RelativeLayout>
</RelativeLayout>

 效果图:

posted on 2017-03-02 20:52  LoaderMan  阅读(302)  评论(0编辑  收藏  举报

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