Android UI自定义ListView实现下拉刷新和加载更多效果

关于实现ListView下拉刷新和加载更多的实现，我想网上一搜就一堆。不过我就没发现比较实用的，要不就是实现起来太复杂，要不就是不健全的。因为小巫近期要开发新浪微博客户端，需要实现ListView的下拉刷新，所以就想把这个UI整合到项目当中去，这里只是一个demo，可以根据项目的需要进行修改。

就不要太在乎界面了哈：

知道你们想要源码了，去下吧：http://download.csdn.net/detail/wwj_748/6373183

自定义ListView：

package com.markupartist.android.widget; 
 
 
import java.lang.reflect.InvocationTargetException; 
import java.lang.reflect.Method; 
 
import com.markupartist.android.example.pulltorefresh.R; 
 
import android.content.Context; 
import android.util.AttributeSet; 
import android.util.Log; 
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.ListAdapter; 
import android.widget.ListView; 
import android.widget.ProgressBar; 
import android.widget.RelativeLayout; 
import android.widget.TextView; 
 
 
 
/** 
 * 2013/8/13 
 * 自定义ListView，实现OnScrollListener接口 
 * 此ListView是为实现"下拉刷新"和"上拉加载更多"而定制的，具体效果可参考新浪微博、腾讯微博 
 * @author wwj 
 * 
 */ 
public class PullToRefreshListView extends ListView implements OnScrollListener { 
 
  private static final int TAP_TO_REFRESH = 1;      //（未刷新） 
  private static final int PULL_TO_REFRESH = 2;      // 下拉刷新 
  private static final int RELEASE_TO_REFRESH = 3;    // 释放刷新 
  private static final int REFRESHING = 4;        // 正在刷新 
  private static final int TAP_TO_LOADMORE = 5;      // 未加载更多 
  private static final int LOADING = 6;          // 正在加载 
   
 
  private static final String TAG = "PullToRefreshListView"; 
 
  private OnRefreshListener mOnRefreshListener;      // 刷新监听器 
 
  /** 
   * Listener that will receive notifications every time the list scrolls. 
   */ 
  private OnScrollListener mOnScrollListener;       // 列表滚动监听器 
  private LayoutInflater mInflater;            // 用于加载布局文件 
 
  private RelativeLayout mRefreshHeaderView;       // 刷新视图(也就是头部那部分)   
  private TextView mRefreshViewText;           // 刷新提示文本     
  private ImageView mRefreshViewImage;          // 刷新向上向下的那个图片 
  private ProgressBar mRefreshViewProgress;        // 这里是圆形进度条 
  private TextView mRefreshViewLastUpdated;        // 最近更新的文本 
   
  private RelativeLayout mLoadMoreFooterView;       // 加载更多 
  private TextView mLoadMoreText;             // 提示文本 
  private ProgressBar mLoadMoreProgress;         // 加载更多进度条 
   
 
  private int mCurrentScrollState;            // 当前滚动位置       
  private int mRefreshState;               // 刷新状态  
  private int mLoadState;                 // 加载状态 
 
  private RotateAnimation mFlipAnimation;         // 下拉动画 
  private RotateAnimation mReverseFlipAnimation;     // 恢复动画 
 
  private int mRefreshViewHeight;             // 刷新视图高度           
  private int mRefreshOriginalTopPadding;         // 原始上部间隙 
  private int mLastMotionY;                // 记录点击位置 
   
  public PullToRefreshListView(Context context) { 
    super(context); 
    init(context); 
  } 
 
  public PullToRefreshListView(Context context, AttributeSet attrs) { 
    super(context, attrs); 
    init(context); 
  } 
 
  public PullToRefreshListView(Context context, AttributeSet attrs, int defStyle) { 
    super(context, attrs, defStyle); 
    init(context); 
  } 
 
  private void init(Context context) { 
    // Load all of the animations we need in code rather than through XML 
    /** 定义旋转动画**/ 
    // 参数：1.旋转开始的角度 2.旋转结束的角度 3. X轴伸缩模式 4.X坐标的伸缩值 5.Y轴的伸缩模式 6.Y坐标的伸缩值 
    mFlipAnimation = new RotateAnimation(0, -180, 
        RotateAnimation.RELATIVE_TO_SELF, 0.5f, 
        RotateAnimation.RELATIVE_TO_SELF, 0.5f); 
    mFlipAnimation.setInterpolator(new LinearInterpolator()); 
    mFlipAnimation.setDuration(250);        // 设置持续时间 
    mFlipAnimation.setFillAfter(true);       // 动画执行完是否停留在执行完的状态 
    mReverseFlipAnimation = new RotateAnimation(-180, 0, 
        RotateAnimation.RELATIVE_TO_SELF, 0.5f, 
        RotateAnimation.RELATIVE_TO_SELF, 0.5f); 
    mReverseFlipAnimation.setInterpolator(new LinearInterpolator()); 
    mReverseFlipAnimation.setDuration(250); 
    mReverseFlipAnimation.setFillAfter(true); 
 
    // 获取LayoutInflater实例对象 
    mInflater = (LayoutInflater) context.getSystemService( 
        Context.LAYOUT_INFLATER_SERVICE); 
 
    // 加载下拉刷新的头部视图 
    mRefreshHeaderView = (RelativeLayout) mInflater.inflate( 
        R.layout.pull_to_refresh_header, this, false); 
    mRefreshViewText = 
      (TextView) mRefreshHeaderView.findViewById(R.id.pull_to_refresh_text); 
    mRefreshViewImage = 
      (ImageView) mRefreshHeaderView.findViewById(R.id.pull_to_refresh_image); 
    mRefreshViewProgress = 
      (ProgressBar) mRefreshHeaderView.findViewById(R.id.pull_to_refresh_progress); 
    mRefreshViewLastUpdated = 
      (TextView) mRefreshHeaderView.findViewById(R.id.pull_to_refresh_updated_at); 
    mLoadMoreFooterView = (RelativeLayout) mInflater.inflate( 
        R.layout.loadmore_footer, this, false); 
    mLoadMoreText = (TextView) mLoadMoreFooterView.findViewById(R.id.loadmore_text); 
    mLoadMoreProgress = (ProgressBar) mLoadMoreFooterView.findViewById(R.id.loadmore_progress); 
     
 
    mRefreshViewImage.setMinimumHeight(50);   // 设置图片最小高度 
    mRefreshHeaderView.setOnClickListener(new OnClickRefreshListener()); 
    mRefreshOriginalTopPadding = mRefreshHeaderView.getPaddingTop(); 
    mLoadMoreFooterView.setOnClickListener(new OnClickLoadMoreListener()); 
 
    mRefreshState = TAP_TO_REFRESH;       // 初始刷新状态 
    mLoadState = TAP_TO_LOADMORE; 
 
    addHeaderView(mRefreshHeaderView);     // 增加头部视图 
    addFooterView(mLoadMoreFooterView);     // 增加尾部视图 
 
    super.setOnScrollListener(this);     
 
    measureView(mRefreshHeaderView);        // 测量视图 
    mRefreshViewHeight = mRefreshHeaderView.getMeasuredHeight();  // 得到视图的高度 
  } 
 
  @Override 
  protected void onAttachedToWindow() { 
    setSelection(1);    // 设置当前选中的项 
  } 
 
  @Override 
  public void setAdapter(ListAdapter adapter) { 
    super.setAdapter(adapter); 
 
    setSelection(1); 
  } 
 
  /** 
   * Set the listener that will receive notifications every time the list 
   * scrolls. 
   * 
   * @param l The scroll listener. 
   */ 
  @Override 
  public void setOnScrollListener(AbsListView.OnScrollListener l) { 
    mOnScrollListener = l; 
  } 
 
  /** 
   * Register a callback to be invoked when this list should be refreshed. 
   * 注册监听器 
   * @param onRefreshListener The callback to run. 
   */ 
  public void setOnRefreshListener(OnRefreshListener onRefreshListener) { 
    mOnRefreshListener = onRefreshListener; 
  } 
 
  /** 
   * Set a text to represent when the list was last updated. 
   * 设置一个文本来表示最近更新的列表，显示的是最近更新列表的时间 
   * @param lastUpdated Last updated at. 
   */ 
  public void setLastUpdated(CharSequence lastUpdated) { 
    if (lastUpdated != null) { 
      mRefreshViewLastUpdated.setVisibility(View.VISIBLE); 
      mRefreshViewLastUpdated.setText("更新于: " + lastUpdated); 
    } else { 
      mRefreshViewLastUpdated.setVisibility(View.GONE); 
    } 
  } 
 
  @Override 
  public boolean onTouchEvent(MotionEvent event) { 
    final int y = (int) event.getY();  // 获取点击位置的Y坐标 
 
    switch (event.getAction()) { 
      case MotionEvent.ACTION_UP:   // 手指抬起 
        if (!isVerticalScrollBarEnabled()) { 
          setVerticalScrollBarEnabled(true); 
        } 
        if (getFirstVisiblePosition() == 0 && mRefreshState != REFRESHING) { 
          if ((mRefreshHeaderView.getBottom() > mRefreshViewHeight 
              || mRefreshHeaderView.getTop() >= 0) 
              && mRefreshState == RELEASE_TO_REFRESH) { 
            // Initiate the refresh 
            mRefreshState = REFRESHING;   // 刷新状态 
            prepareForRefresh(); 
            onRefresh(); 
          } else if (mRefreshHeaderView.getBottom() < mRefreshViewHeight 
              || mRefreshHeaderView.getTop() < 0) { 
            // Abort refresh and scroll down below the refresh view 
            resetHeader(); 
            setSelection(1); 
          } 
        } 
        break; 
      case MotionEvent.ACTION_DOWN: 
        mLastMotionY = y; 
        break; 
      case MotionEvent.ACTION_MOVE: 
        applyHeaderPadding(event); 
        break; 
    } 
    return super.onTouchEvent(event); 
  } 
 
  private void applyHeaderPadding(MotionEvent ev) { 
    final int historySize = ev.getHistorySize(); 
 
    // Workaround for getPointerCount() which is unavailable in 1.5 
    // (it's always 1 in 1.5) 
    int pointerCount = 1; 
    try { 
      Method method = MotionEvent.class.getMethod("getPointerCount"); 
      pointerCount = (Integer)method.invoke(ev); 
    } catch (NoSuchMethodException e) { 
      pointerCount = 1; 
    } catch (IllegalArgumentException e) { 
      throw e; 
    } catch (IllegalAccessException e) { 
      System.err.println("unexpected " + e); 
    } catch (InvocationTargetException e) { 
      System.err.println("unexpected " + e); 
    } 
 
    for (int h = 0; h < historySize; h++) { 
      for (int p = 0; p < pointerCount; p++) { 
        if (mRefreshState == RELEASE_TO_REFRESH) { 
          if (isVerticalFadingEdgeEnabled()) { 
            setVerticalScrollBarEnabled(false); 
          } 
 
          int historicalY = 0; 
          try { 
            // For Android > 2.0 
            Method method = MotionEvent.class.getMethod( 
                "getHistoricalY", Integer.TYPE, Integer.TYPE); 
            historicalY = ((Float) method.invoke(ev, p, h)).intValue(); 
          } catch (NoSuchMethodException e) { 
            // For Android < 2.0 
            historicalY = (int) (ev.getHistoricalY(h)); 
          } catch (IllegalArgumentException e) { 
            throw e; 
          } catch (IllegalAccessException e) { 
            System.err.println("unexpected " + e); 
          } catch (InvocationTargetException e) { 
            System.err.println("unexpected " + e); 
          } 
 
          // Calculate the padding to apply, we divide by 1.7 to 
          // simulate a more resistant effect during pull. 
          int topPadding = (int) (((historicalY - mLastMotionY) 
              - mRefreshViewHeight) / 1.7); 
 
          // 设置上、下、左、右四个位置的间隙间隙 
          mRefreshHeaderView.setPadding( 
              mRefreshHeaderView.getPaddingLeft(), 
              topPadding, 
              mRefreshHeaderView.getPaddingRight(), 
              mRefreshHeaderView.getPaddingBottom()); 
        } 
      } 
    } 
  } 
 
  /** 
   * Sets the header padding back to original size. 
   * 设置头部填充会原始大小 
   */ 
  private void resetHeaderPadding() { 
    mRefreshHeaderView.setPadding( 
        mRefreshHeaderView.getPaddingLeft(), 
        mRefreshOriginalTopPadding, 
        mRefreshHeaderView.getPaddingRight(), 
        mRefreshHeaderView.getPaddingBottom()); 
  } 
 
  /** 
   * Resets the header to the original state. 
   * 重新设置头部为原始状态 
   */ 
  private void resetHeader() { 
    if (mRefreshState != TAP_TO_REFRESH) { 
      mRefreshState = TAP_TO_REFRESH; 
 
      resetHeaderPadding(); 
 
      // Set refresh view text to the pull label 
      mRefreshViewText.setText(R.string.pull_to_refresh_tap_label); 
      // Replace refresh drawable with arrow drawable 
      mRefreshViewImage.setImageResource(R.drawable.ic_pulltorefresh_arrow); 
      // Clear the full rotation animation 
      mRefreshViewImage.clearAnimation(); 
      // Hide progress bar and arrow. 
      mRefreshViewImage.setVisibility(View.GONE); 
      mRefreshViewProgress.setVisibility(View.GONE); 
    } 
  } 
   
  /** 
   * 重设ListView尾部视图为初始状态 
   */ 
  private void resetFooter() { 
    if(mLoadState != TAP_TO_LOADMORE) { 
      mLoadState = TAP_TO_LOADMORE; 
       
      // 进度条设置为不可见 
      mLoadMoreProgress.setVisibility(View.GONE); 
      // 按钮的文本替换为“加载更多” 
      mLoadMoreText.setText(R.string.loadmore_label); 
    } 
     
  } 
   
 
  /** 
   * 测量视图的大小 
   * @param child 
   */ 
  private void measureView(View child) { 
    ViewGroup.LayoutParams p = child.getLayoutParams(); 
    if (p == null) { 
      p = new ViewGroup.LayoutParams( 
          ViewGroup.LayoutParams.MATCH_PARENT, 
          ViewGroup.LayoutParams.WRAP_CONTENT); 
    } 
 
    int childWidthSpec = ViewGroup.getChildMeasureSpec(0, 
        0 + 0, p.width); 
    int lpHeight = p.height; 
    int childHeightSpec; 
    if (lpHeight > 0) { 
      childHeightSpec = MeasureSpec.makeMeasureSpec(lpHeight, MeasureSpec.EXACTLY); 
    } else { 
      childHeightSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED); 
    } 
    child.measure(childWidthSpec, childHeightSpec); 
  } 
 
  @Override 
  public void onScroll(AbsListView view, int firstVisibleItem, 
      int visibleItemCount, int totalItemCount) { 
    // When the refresh view is completely visible, change the text to say 
    // "Release to refresh..." and flip the arrow drawable. 
    if (mCurrentScrollState == SCROLL_STATE_TOUCH_SCROLL 
        && mRefreshState != REFRESHING) { 
      if (firstVisibleItem == 0) {    // 如果第一个可见条目为0 
        mRefreshViewImage.setVisibility(View.VISIBLE); // 让指示箭头变得可见 
        /**如果头部视图相对与父容器的位置大于其自身高度+20或者头部视图的顶部位置>0,并且要在刷新状态不等于"释放以刷新"**/ 
        if ((mRefreshHeaderView.getBottom() > mRefreshViewHeight + 20 
            || mRefreshHeaderView.getTop() >= 0) 
            && mRefreshState != RELEASE_TO_REFRESH) { 
          mRefreshViewText.setText(R.string.pull_to_refresh_release_label);// 设置刷新文本为"Release to refresh..." 
          mRefreshViewImage.clearAnimation();         // 清除动画  
          mRefreshViewImage.startAnimation(mFlipAnimation);  // 启动动画 
          mRefreshState = RELEASE_TO_REFRESH;         // 更改刷新状态为“释放以刷新" 
        } else if (mRefreshHeaderView.getBottom() < mRefreshViewHeight + 20 
            && mRefreshState != PULL_TO_REFRESH) { 
          mRefreshViewText.setText(R.string.pull_to_refresh_pull_label);// 设置刷新文本为"Pull to refresh..." 
          if (mRefreshState != TAP_TO_REFRESH) { 
            mRefreshViewImage.clearAnimation(); 
            mRefreshViewImage.startAnimation(mReverseFlipAnimation); 
          } 
          mRefreshState = PULL_TO_REFRESH; 
        } 
      } else { 
        mRefreshViewImage.setVisibility(View.GONE);     // 让刷新箭头不可见 
        resetHeader(); // 重新设置头部为原始状态 
      } 
    } else if (mCurrentScrollState == SCROLL_STATE_FLING 
        && firstVisibleItem == 0 
        && mRefreshState != REFRESHING) { 
      setSelection(1); 
    } 
 
    if (mOnScrollListener != null) { 
      mOnScrollListener.onScroll(view, firstVisibleItem, 
          visibleItemCount, totalItemCount); 
    } 
  } 
 
  @Override 
  public void onScrollStateChanged(AbsListView view, int scrollState) { 
    mCurrentScrollState = scrollState; 
 
    if (mOnScrollListener != null) { 
      mOnScrollListener.onScrollStateChanged(view, scrollState); 
    } 
  } 
   
 
  /**为刷新做准备**/ 
  public void prepareForRefresh() { 
    resetHeaderPadding();     
 
    mRefreshViewImage.setVisibility(View.GONE);     // 去掉刷新的箭头 
    // We need this hack, otherwise it will keep the previous drawable. 
    mRefreshViewImage.setImageDrawable(null); 
    mRefreshViewProgress.setVisibility(View.VISIBLE);  // 圆形进度条变为可见 
 
    // Set refresh view text to the refreshing label 
    mRefreshViewText.setText(R.string.pull_to_refresh_refreshing_label); 
 
    mRefreshState = REFRESHING; 
  } 
   
  /**为加载更多做准备**/ 
  public void prepareForLoadMore() { 
    mLoadMoreProgress.setVisibility(View.VISIBLE);   
    mLoadMoreText.setText(R.string.loading_label); 
    mLoadState = LOADING; 
  } 
 
  public void onRefresh() { 
    Log.d(TAG, "onRefresh"); 
 
    if (mOnRefreshListener != null) { 
      mOnRefreshListener.onRefresh(); 
    } 
  } 
   
  public void OnLoadMore() { 
    Log.d(TAG, "onLoadMore"); 
    if(mOnRefreshListener != null) { 
      mOnRefreshListener.onLoadMore(); 
    } 
  } 
 
  /** 
   * Resets the list to a normal state after a refresh. 
   * @param lastUpdated Last updated at. 
   */ 
  public void onRefreshComplete(CharSequence lastUpdated) { 
    setLastUpdated(lastUpdated);  // 显示更新时间 
    onRefreshComplete(); 
  } 
 
  /** 
   * Resets the list to a normal state after a refresh. 
   */ 
  public void onRefreshComplete() {     
    Log.d(TAG, "onRefreshComplete"); 
 
    resetHeader(); 
 
    // If refresh view is visible when loading completes, scroll down to 
    // the next item. 
    if (mRefreshHeaderView.getBottom() > 0) { 
      invalidateViews(); 
      setSelection(1); 
    } 
  } 
   
  public void onLoadMoreComplete() { 
    Log.d(TAG, "onLoadMoreComplete"); 
    resetFooter(); 
  } 
 
  /** 
   * Invoked when the refresh view is clicked on. This is mainly used when 
   * there's only a few items in the list and it's not possible to drag the 
   * list. 
   * 点击刷新 
   */ 
  private class OnClickRefreshListener implements OnClickListener { 
 
    @Override 
    public void onClick(View v) { 
      if (mRefreshState != REFRESHING) { 
        prepareForRefresh(); 
        onRefresh(); 
      } 
    } 
 
  } 
   
  /** 
   * 
   * @author wwj 
   * 加载更多 
   */ 
  private class OnClickLoadMoreListener implements OnClickListener { 
 
    @Override 
    public void onClick(View v) { 
      if(mLoadState != LOADING) { 
        prepareForLoadMore(); 
        OnLoadMore(); 
      } 
    } 
  } 
 
  /** 
   * Interface definition for a callback to be invoked when list should be 
   * refreshed. 
   * 接口定义一个回调方法当列表应当被刷新 
   */ 
  public interface OnRefreshListener { 
    /** 
     * Called when the list should be refreshed. 
     * 当列表应当被刷新是调用这个方法 
     * 
 
     * A call to {@link PullToRefreshListView #onRefreshComplete()} is 
     * expected to indicate that the refresh has completed. 
     */ 
    public void onRefresh(); 
     
    public void onLoadMore(); 
  } 
} 

使用方法：

package com.markupartist.android.example.pulltorefresh; 
 
import java.text.SimpleDateFormat; 
import java.util.Arrays; 
import java.util.Date; 
import java.util.LinkedList; 
 
import android.app.Activity; 
import android.content.Context; 
import android.os.AsyncTask; 
import android.os.Bundle; 
import android.widget.ArrayAdapter; 
 
import com.markupartist.android.widget.PullToRefreshListView; 
import com.markupartist.android.widget.PullToRefreshListView.OnRefreshListener; 
 
public class PullToRefreshActivity extends Activity { 
  private LinkedList mListItems; 
  public static PullToRefreshListView weiboListView; 
 
  /** Called when the activity is first created. */ 
  @Override 
  public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.pull_to_refresh); 
    weiboListView = (PullToRefreshListView) findViewById(R.id.weibolist); 
 
    // Set a listener to be invoked when the list should be refreshed. 
    weiboListView.setOnRefreshListener(new OnRefreshListener() { 
      @Override 
      public void onRefresh() { 
        // Do work to refresh the list here. 
        new GetDataTask(PullToRefreshActivity.this, 0).execute(); 
      } 
 
      @Override 
      public void onLoadMore() { 
        new GetDataTask(PullToRefreshActivity.this, 1).execute(); 
      } 
    }); 
 
    mListItems = new LinkedList(); 
    mListItems.addAll(Arrays.asList(mStrings)); 
 
    ArrayAdapter adapter = new ArrayAdapter(this, 
        android.R.layout.simple_list_item_1, mListItems); 
 
    weiboListView.setAdapter(adapter); 
  } 
 
  private class GetDataTask extends AsyncTask { 
    private Context context; 
    private int index; 
 
    public GetDataTask(Context context, int index) { 
      this.context = context; 
      this.index = index; 
    } 
 
    @Override 
    protected String[] doInBackground(Void... params) { 
      // Simulates a background job. 
      try { 
        Thread.sleep(2000); 
      } catch (InterruptedException e) { 
        ; 
      } 
      return mStrings; 
    } 
 
    @Override 
    protected void onPostExecute(String[] result) { 
      if (index == 0) { 
        // 将字符串“Added after refresh”添加到顶部 
        mListItems.addFirst("Added after refresh..."); 
 
        SimpleDateFormat format = new SimpleDateFormat( 
            "yyyy年MM月dd日 HH:mm"); 
        String date = format.format(new Date()); 
        // Call onRefreshComplete when the list has been refreshed. 
        weiboListView.onRefreshComplete(date); 
      } else if (index == 1) { 
        mListItems.addLast("Added after loadmore..."); 
        weiboListView.onLoadMoreComplete(); 
      } 
 
      super.onPostExecute(result); 
    } 
  } 
 
  public static String[] mStrings = { "一条微博", "两条微博", "三条微博", "四条微博", "五条微博", 
      "六条微博", "七条微博", "八条微博", "九条微博", "十条微博", "十一条微博", "十二条微博" }; 
 
} 

下拉刷新的那个头部布局
/2013.08.22_PullToRefresh_ListView_Demo/res/layout/pull_to_refresh_header.xml

加载更多的底部布局
/2013.08.22_PullToRefresh_ListView_Demo/res/layout/loadmore_footer.xml

/2013.08.22_PullToRefresh_ListView_Demo/res/layout/pull_to_refresh.xml

 以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。