ListView装上拉电阻下拉刷新

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mb5fdb0f4aaf587 2015-09-25 12:09:00

文章标签 android 下拉刷新数据 xml ide 文章分类 代码人生

ListView装上拉电阻下拉刷新_下拉刷新

主要用到了这个几个文件。MainActivity是界面的Activity,MyAdapter是ListView的自己定义适配,MyListView是自己定义带头部LIistView，假设仅仅须要上拉载入就不须要；activity_main.xml是住界面。item.xml是ListView的子布局里面仅仅有一个TextView,listview_footer.xml是listview的载入很多其它的底部布局，listview_header.xml是listview的头部布局。

MainActivity.java

package com.example.listview;

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

import android.annotation.SuppressLint;
import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.Toast;

import com.example.listview.MyListView.OnRefreshListener;

public class MainActivity extends Activity implements OnScrollListener{
  /** ListView*/
  private MyListView listView;
  /** 自己定义的Adapter*/
  private MyAdapter adapter;
  /** 一共的数据*/
  private List<String> list=new ArrayList<String>();
  /** ListView的底部布局*/
  private View footer;

  private Handler handler;

  private int count=0;


  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    /** 配置好ListView*/
    listView=(MyListView) findViewById(R.id.listView);

    /** 加入底部布局,要在setAdapter前,否则没有效果*/
    footer=LayoutInflater.from(this).inflate(R.layout.listview_footer, null);
    listView.addFooterView(footer);

    /** 适配listView*/
    adapter=new MyAdapter(this, list);
    listView.setAdapter(adapter);

    /**　加入一个线程设置时间有等待的效果*/
    handler=new Handler();

    listView.setOnScrollListener(this);

    listView.setonRefreshListener(new OnRefreshListener() {

              @Override
           public void onRefresh() {
                  new AsyncTask<Void, Void, Void>() {
                      protected Void doInBackground(Void... params) {
                          try {
                              Thread.sleep(1000);
                          } catch (Exception e) {
                              e.printStackTrace();
                          }
                         // list.add("刷新后加入的内容");
                          return null;
                      }

                      @Override
                      protected void onPostExecute(Void result) {
                          adapter.notifyDataSetChanged();
                          listView.onRefreshComplete();
                      }
                  }.execute(null, null, null);

              }
         });

    setData();  

  }

  /**
   * 底部滚动的监听 
   */
  @Override
  public void onScrollStateChanged(final AbsListView view, int scrollState) {
    /** 当滚动停止同一时候在底部的时候*/
       if (scrollState == OnScrollListener.SCROLL_STATE_IDLE && (view.getLastVisiblePosition() == view.getCount() - 1)) {
          /** 为了有数据载入等待的时间。假设是网络数据请求，则此处不须要直接请求接口就ok*/
                  handler.postDelayed(new Runnable() {

                      @Override
                      public void run() {
                        setData();
                        /** 让刷新出来的数据从屏幕開始显示,假设不设定位置，listView数据更新后会跑到第一条数据開始显示*/
                        listView.setSelection(view.getCount()-1);
                      }

                  }, 2000);

       }

  }
  @Override
  public void onScroll(AbsListView arg0, int arg1, int arg2, int arg3) {

  }
  /** 放数据,假设你的数据能够分页获取就不须要这样,此处是为了有分页的数据*/
  @SuppressLint("ShowToast")
  private void setData(){

    //当数据到达总量的时候移除底部布局
    if(count>50){

      listView.removeFooterView(footer);

      Toast.makeText(this,"没有很多其它数据", 500).show();

      return;
    }

    for(int i=count;i<count+10;i++){


      list.add("数据"+i);

    }

    count=count+10;
    /** 通知adapter数据改变*/
    adapter.notifyDataSetChanged();
  }
}

MyListView.java

package com.example.listview;

import java.util.Date;

import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.LinearInterpolator;
import android.view.animation.RotateAnimation;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;
/**
 * ListView加入刷新头部自己定义的ListView
 * 
 * @author 刘梓未
 * 
 *
 */
public class MyListView extends ListView implements OnScrollListener {

    private final static int RELEASE_To_REFRESH = 0;// 下拉过程的状态值
    private final static int PULL_To_REFRESH = 1; // 从下拉返回到不刷新的状态值
    private final static int REFRESHING = 2;// 正在刷新的状态值
    private final static int DONE = 3;
    private final static int LOADING = 4;

    // 实际的padding的距离与界面上偏移距离的比例
    private final static int RATIO = 3;
    private LayoutInflater inflater;

    // ListView头部下拉刷新的布局
    private LinearLayout headerView;
    private TextView lvHeaderTipsTv;
    private TextView lvHeaderLastUpdatedTv;
    private ImageView lvHeaderArrowIv;
    private ProgressBar lvHeaderProgressBar;

    // 定义头部下拉刷新的布局的高度
    private int headerContentHeight;

    private RotateAnimation animation;
    private RotateAnimation reverseAnimation;

    private int startY;
    private int state;
    private boolean isBack;

    // 用于保证startY的值在一个完整的touch事件中仅仅被记录一次
    private boolean isRecored;

    private OnRefreshListener refreshListener;

    private boolean isRefreshable;

    public MyListView(Context context) {
        super(context);
        init(context);
    }

    public MyListView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context);
    }

    private void init(Context context) {
        setCacheColorHint(context.getResources().getColor(android.R.color.transparent));
        inflater = LayoutInflater.from(context);
        headerView = (LinearLayout) inflater.inflate(R.layout.listview_header, null);
        lvHeaderTipsTv = (TextView) headerView
                .findViewById(R.id.lvHeaderTipsTv);
        lvHeaderLastUpdatedTv = (TextView) headerView
                .findViewById(R.id.lvHeaderLastUpdatedTv);

        lvHeaderArrowIv = (ImageView) headerView
                .findViewById(R.id.lvHeaderArrowIv);
        // 设置下拉刷新图标的最小高度和宽度
        lvHeaderArrowIv.setMinimumWidth(70);
        lvHeaderArrowIv.setMinimumHeight(50);

        lvHeaderProgressBar = (ProgressBar) headerView
                .findViewById(R.id.lvHeaderProgressBar);
        measureView(headerView);
        headerContentHeight = headerView.getMeasuredHeight();
        // 设置内边距，正好距离顶部为一个负的整个布局的高度，正好把头部隐藏
        headerView.setPadding(0, -1 * headerContentHeight, 0, 0);
        // 重绘一下
        headerView.invalidate();
        // 将下拉刷新的布局加入ListView的顶部
        addHeaderView(headerView, null, false);
        // 设置滚动监听事件
        setOnScrollListener(this);

        // 设置旋转动画事件
        animation = new RotateAnimation(0, -180,
                RotateAnimation.RELATIVE_TO_SELF, 0.5f,
                RotateAnimation.RELATIVE_TO_SELF, 0.5f);
        animation.setInterpolator(new LinearInterpolator());
        animation.setDuration(250);
        animation.setFillAfter(true);

        reverseAnimation = new RotateAnimation(-180, 0,
                RotateAnimation.RELATIVE_TO_SELF, 0.5f,
                RotateAnimation.RELATIVE_TO_SELF, 0.5f);
        reverseAnimation.setInterpolator(new LinearInterpolator());
        reverseAnimation.setDuration(200);
        reverseAnimation.setFillAfter(true);

        // 一開始的状态就是下拉刷新完的状态。所以为DONE
        state = DONE;
        // 是否正在刷新
        isRefreshable = false;
    }

    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {

    }

    @Override
    public void onScroll(AbsListView view, int firstVisibleItem,
            int visibleItemCount, int totalItemCount) {
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        if (isRefreshable) {
            switch (ev.getAction()) {
            case MotionEvent.ACTION_DOWN:
                if (!isRecored) {
                    isRecored = true;
                    startY = (int) ev.getY();// 手指按下时记录当前位置
                }
                break;
            case MotionEvent.ACTION_UP:
                if (state != REFRESHING && state != LOADING) {
                    if (state == PULL_To_REFRESH) {
                        state = DONE;
                        changeHeaderViewByState();
                    }
                    if (state == RELEASE_To_REFRESH) {
                        state = REFRESHING;
                        changeHeaderViewByState();
                        onLvRefresh();
                    }
                }
                isRecored = false;
                isBack = false;

                break;

            case MotionEvent.ACTION_MOVE:
                int tempY = (int) ev.getY();
                if (!isRecored) {
                    isRecored = true;
                    startY = tempY;
                }
                if (state != REFRESHING && isRecored && state != LOADING) {
                    // 保证在设置padding的过程中，当前的位置一直是在head。否则假设当列表超出屏幕的话，当在上推的时候。列表会同一时候进行滚动
                    // 能够松手去刷新了
                    if (state == RELEASE_To_REFRESH) {
                        setSelection(0);
                        // 往上推了。推到了屏幕足够掩盖head的程度，可是还没有推到所有掩盖的地步
                        if (((tempY - startY) / RATIO < headerContentHeight)// 由松开刷新状态转变到下拉刷新状态
                                && (tempY - startY) > 0) {
                            state = PULL_To_REFRESH;
                            changeHeaderViewByState();
                        }
                        // 一下子推到顶了
                        else if (tempY - startY <= 0) {// 由松开刷新状态转变到done状态
                            state = DONE;
                            changeHeaderViewByState();
                        }
                    }
                    // 还没有到达显示松开刷新的时候,DONE或者是PULL_To_REFRESH状态
                    if (state == PULL_To_REFRESH) {
                        setSelection(0);
                        // 下拉到能够进入RELEASE_TO_REFRESH的状态
                        if ((tempY - startY) / RATIO >= headerContentHeight) {// 由done或者下拉刷新状态转变到松开刷新
                            state = RELEASE_To_REFRESH;
                            isBack = true;
                            changeHeaderViewByState();
                        }
                        // 上推到顶了
                        else if (tempY - startY <= 0) {// 由DOne或者下拉刷新状态转变到done状态
                            state = DONE;
                            changeHeaderViewByState();
                        }
                    }
                    // done状态下
                    if (state == DONE) {
                        if (tempY - startY > 0) {
                            state = PULL_To_REFRESH;
                            changeHeaderViewByState();
                        }
                    }
                    // 更新headView的size
                    if (state == PULL_To_REFRESH) {
                        headerView.setPadding(0, -1 * headerContentHeight
                                + (tempY - startY) / RATIO, 0, 0);

                    }
                    // 更新headView的paddingTop
                    if (state == RELEASE_To_REFRESH) {
                        headerView.setPadding(0, (tempY - startY) / RATIO
                                - headerContentHeight, 0, 0);
                    }

                }
                break;

            default:
                break;
            }
        }
        return super.onTouchEvent(ev);
    }

    // 当状态改变时候。调用该方法。以更新界面
    private void changeHeaderViewByState() {
        switch (state) {
        case RELEASE_To_REFRESH:
            lvHeaderArrowIv.setVisibility(View.VISIBLE);
            lvHeaderProgressBar.setVisibility(View.GONE);
            lvHeaderTipsTv.setVisibility(View.VISIBLE);
            lvHeaderLastUpdatedTv.setVisibility(View.VISIBLE);

            lvHeaderArrowIv.clearAnimation();// 清除动画
            lvHeaderArrowIv.startAnimation(animation);// 開始动画效果

            lvHeaderTipsTv.setText("松开刷新");
            break;
        case PULL_To_REFRESH:
            lvHeaderProgressBar.setVisibility(View.GONE);
            lvHeaderTipsTv.setVisibility(View.VISIBLE);
            lvHeaderLastUpdatedTv.setVisibility(View.VISIBLE);
            lvHeaderArrowIv.clearAnimation();
            lvHeaderArrowIv.setVisibility(View.VISIBLE);
            // 是由RELEASE_To_REFRESH状态转变来的
            if (isBack) {
                isBack = false;
                lvHeaderArrowIv.clearAnimation();
                lvHeaderArrowIv.startAnimation(reverseAnimation);

                lvHeaderTipsTv.setText("下拉刷新");
            } else {
                lvHeaderTipsTv.setText("下拉刷新");
            }
            break;

        case REFRESHING:

            headerView.setPadding(0, 0, 0, 0);

            lvHeaderProgressBar.setVisibility(View.VISIBLE);
            lvHeaderArrowIv.clearAnimation();
            lvHeaderArrowIv.setVisibility(View.GONE);
            lvHeaderTipsTv.setText("正在刷新...");
            lvHeaderLastUpdatedTv.setVisibility(View.VISIBLE);
            break;
        case DONE:
            headerView.setPadding(0, -1 * headerContentHeight, 0, 0);

            lvHeaderProgressBar.setVisibility(View.GONE);
            lvHeaderArrowIv.clearAnimation();
            lvHeaderArrowIv.setImageResource(R.drawable.head_arrow);
            lvHeaderTipsTv.setText("下拉刷新");
            lvHeaderLastUpdatedTv.setVisibility(View.VISIBLE);
            break;
        }
    }

    // 此方法直接照搬自网络上的一个下拉刷新的demo，此处是“预计”headView的width以及height
    private void measureView(View child) {
        ViewGroup.LayoutParams params = child.getLayoutParams();
        if (params == null) {
            params = new ViewGroup.LayoutParams(
                    ViewGroup.LayoutParams.MATCH_PARENT,
                    ViewGroup.LayoutParams.WRAP_CONTENT);
        }
        int childWidthSpec = ViewGroup.getChildMeasureSpec(0, 0 + 0,
                params.width);
        int lpHeight = params.height;
        int childHeightSpec;
        if (lpHeight > 0) {
            childHeightSpec = MeasureSpec.makeMeasureSpec(lpHeight,
                    MeasureSpec.EXACTLY);
        } else {
            childHeightSpec = MeasureSpec.makeMeasureSpec(0,
                    MeasureSpec.UNSPECIFIED);
        }
        child.measure(childWidthSpec, childHeightSpec);
    }

    public void setonRefreshListener(OnRefreshListener refreshListener) {
        this.refreshListener = refreshListener;
        isRefreshable = true;
    }

    public interface OnRefreshListener {
        public void onRefresh();
    }

    @SuppressWarnings("deprecation")
    public void onRefreshComplete() {
        state = DONE;
        lvHeaderLastUpdatedTv.setText("近期更新:" + new Date().toLocaleString());
        changeHeaderViewByState();
    }

    private void onLvRefresh() {
        if (refreshListener != null) {
            refreshListener.onRefresh();
        }
    }



}

listview_footer.xml

<?xml version="1.0" encoding="utf-8"?
>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:gravity="center"
    android:layout_marginTop="10dp"
    android:orientation="horizontal" >

    <ProgressBar 
        android:id="@+id/footer_progress"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        />

</LinearLayout>

listview_header.xml

ListView装上拉电阻下拉刷新_android_02

<?xml version="1.0" encoding="utf-8"?>
<!-- ListView的头部 -->
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    >

    <!-- 内容 -->

    <RelativeLayout
        android:id="@+id/head_contentLayout"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/list_header_bg"
        android:paddingLeft="30dp">

        <!-- 箭头图像、进度条 -->

        <FrameLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_centerVertical="true" >

            <!-- 箭头 -->

            <ImageView
                android:id="@+id/lvHeaderArrowIv"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:src="@drawable/head_arrow" />

            <!-- 进度条 -->

            <ProgressBar
                android:id="@+id/lvHeaderProgressBar"
                style="?android:attr/progressBarStyleSmall"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:visibility="gone" />
        </FrameLayout>

        <!-- 提示、近期更新 -->

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:gravity="center_horizontal"
            android:orientation="vertical" >

            <!-- 提示 -->

            <TextView
                android:id="@+id/lvHeaderTipsTv"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="下拉刷新"
                android:textSize="13sp" />

            <!-- 近期更新 -->

            <TextView
                android:id="@+id/lvHeaderLastUpdatedTv"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="最新更新"
                android:textSize="10sp" />
        </LinearLayout>
    </RelativeLayout>

</LinearLayout>