android下拉刷新上拉加载简单的实现方法；

项目中需要用到android下拉刷新和上拉加载；所以学习了一个很简单的很方便的一个例子；自己也写过下拉刷新和上拉加载的功能；但是如果每个界面都要实现这个功能的话非常的麻烦；所以学习了别人很好的demo；然后分享一下；

我的学习步骤；

在网上下载demo；然后把必要的导入到项目中；

在此附上下载源码网址：http://download.csdn.net/detail/android_drawing/8596553

所有的源代码如下；

XListViewFooter类

/**
 * @file XFooterView.java
 * @create Mar 31, 2012 9:33:43 PM
 * @author Maxwin
 * @description XListView's footer
 */
package me.maxwin.view;

import me.maxwin.R;
import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;

public class XListViewFooter extends LinearLayout {
	public final static int STATE_NORMAL = 0;
	public final static int STATE_READY = 1;
	public final static int STATE_LOADING = 2;

	private Context mContext;

	private View mContentView;
	private View mProgressBar;
	private TextView mHintView;

	public XListViewFooter(Context context) {
		super(context);
		initView(context);
	}

	public XListViewFooter(Context context, AttributeSet attrs) {
		super(context, attrs);
		initView(context);
	}

	public void setState(int state) {
		mHintView.setVisibility(View.INVISIBLE);
		mProgressBar.setVisibility(View.INVISIBLE);
		mHintView.setVisibility(View.INVISIBLE);
		if (state == STATE_READY) {
			mHintView.setVisibility(View.VISIBLE);
			mHintView.setText(R.string.xlistview_footer_hint_ready);
		} else if (state == STATE_LOADING) {
			mProgressBar.setVisibility(View.VISIBLE);
		} else {
			mHintView.setVisibility(View.VISIBLE);
			mHintView.setText(R.string.xlistview_footer_hint_normal);
		}
	}

	public void setBottomMargin(int height) {
		if (height < 0) return ;
		LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams)mContentView.getLayoutParams();
		lp.bottomMargin = height;
		mContentView.setLayoutParams(lp);
	}

	public int getBottomMargin() {
		LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams)mContentView.getLayoutParams();
		return lp.bottomMargin;
	}

	/**
	 * normal status
	 */
	public void normal() {
		mHintView.setVisibility(View.VISIBLE);
		mProgressBar.setVisibility(View.GONE);
	}

	/**
	 * loading status
	 */
	public void loading() {
		mHintView.setVisibility(View.GONE);
		mProgressBar.setVisibility(View.VISIBLE);
	}

	/**
	 * hide footer when disable pull load more
	 */
	public void hide() {
		LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams)mContentView.getLayoutParams();
		lp.height = 0;
		mContentView.setLayoutParams(lp);
	}

	/**
	 * show footer
	 */
	public void show() {
		LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams)mContentView.getLayoutParams();
		lp.height = LayoutParams.WRAP_CONTENT;
		mContentView.setLayoutParams(lp);
	}

	private void initView(Context context) {
		mContext = context;
		LinearLayout moreView = (LinearLayout)LayoutInflater.from(mContext).inflate(R.layout.xlistview_footer, null);
		addView(moreView);
		moreView.setLayoutParams(new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));

		mContentView = moreView.findViewById(R.id.xlistview_footer_content);
		mProgressBar = moreView.findViewById(R.id.xlistview_footer_progressbar);
		mHintView = (TextView)moreView.findViewById(R.id.xlistview_footer_hint_textview);
	}

}

XListViewHeader类

/**
 * @file XListViewHeader.java
 * @create Apr 18, 2012 5:22:27 PM
 * @author Maxwin
 * @description XListView's header
 */
package me.maxwin.view;

import me.maxwin.R;
import android.content.Context;
import android.util.AttributeSet;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.RotateAnimation;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ProgressBar;
import android.widget.TextView;

public class XListViewHeader extends LinearLayout {
	private LinearLayout mContainer;
	private ImageView mArrowImageView;
	private ProgressBar mProgressBar;
	private TextView mHintTextView;
	private int mState = STATE_NORMAL;

	private Animation mRotateUpAnim;
	private Animation mRotateDownAnim;

	private final int ROTATE_ANIM_DURATION = 180;

	public final static int STATE_NORMAL = 0;
	public final static int STATE_READY = 1;
	public final static int STATE_REFRESHING = 2;

	public XListViewHeader(Context context) {
		super(context);
		initView(context);
	}

	/**
	 * @param context
	 * @param attrs
	 */
	public XListViewHeader(Context context, AttributeSet attrs) {
		super(context, attrs);
		initView(context);
	}

	private void initView(Context context) {
		// 鍒濆鎯呭喌锛岃缃笅鎷夊埛鏂皏iew楂樺害涓?0
		LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
				LayoutParams.FILL_PARENT, 0);
		mContainer = (LinearLayout) LayoutInflater.from(context).inflate(
				R.layout.xlistview_header, null);
		addView(mContainer, lp);
		setGravity(Gravity.BOTTOM);

		mArrowImageView = (ImageView)findViewById(R.id.xlistview_header_arrow);
		mHintTextView = (TextView)findViewById(R.id.xlistview_header_hint_textview);
		mProgressBar = (ProgressBar)findViewById(R.id.xlistview_header_progressbar);

		mRotateUpAnim = new RotateAnimation(0.0f, -180.0f,
				Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
				0.5f);
		mRotateUpAnim.setDuration(ROTATE_ANIM_DURATION);
		mRotateUpAnim.setFillAfter(true);
		mRotateDownAnim = new RotateAnimation(-180.0f, 0.0f,
				Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
				0.5f);
		mRotateDownAnim.setDuration(ROTATE_ANIM_DURATION);
		mRotateDownAnim.setFillAfter(true);
	}

	public void setState(int state) {
		if (state == mState) return ;

		if (state == STATE_REFRESHING) {	// 鏄剧ず杩涘害
			mArrowImageView.clearAnimation();
			mArrowImageView.setVisibility(View.INVISIBLE);
			mProgressBar.setVisibility(View.VISIBLE);
		} else {	// 鏄剧ず绠ご鍥剧墖
			mArrowImageView.setVisibility(View.VISIBLE);
			mProgressBar.setVisibility(View.INVISIBLE);
		}

		switch(state){
		case STATE_NORMAL:
			if (mState == STATE_READY) {
				mArrowImageView.startAnimation(mRotateDownAnim);
			}
			if (mState == STATE_REFRESHING) {
				mArrowImageView.clearAnimation();
			}
			mHintTextView.setText(R.string.xlistview_header_hint_normal);
			break;
		case STATE_READY:
			if (mState != STATE_READY) {
				mArrowImageView.clearAnimation();
				mArrowImageView.startAnimation(mRotateUpAnim);
				mHintTextView.setText(R.string.xlistview_header_hint_ready);
			}
			break;
		case STATE_REFRESHING:
			mHintTextView.setText(R.string.xlistview_header_hint_loading);
			break;
			default:
		}

		mState = state;
	}

	public void setVisiableHeight(int height) {
		if (height < 0)
			height = 0;
		LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) mContainer
				.getLayoutParams();
		lp.height = height;
		mContainer.setLayoutParams(lp);
	}

	public int getVisiableHeight() {
		return mContainer.getLayoutParams().height;
	}

}

XListView类

/**
 * @file XListView.java
 * @package me.maxwin.view
 * @create Mar 18, 2012 6:28:41 PM
 * @author Maxwin
 * @description An ListView support (a) Pull down to refresh, (b) Pull up to load more.
 * 		Implement IXListViewListener, and see stopRefresh() / stopLoadMore().
 */
package me.maxwin.view;

import me.maxwin.R;
import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewTreeObserver.OnGlobalLayoutListener;
import android.view.animation.DecelerateInterpolator;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.Scroller;
import android.widget.TextView;

public class XListView extends ListView implements OnScrollListener {

	private float mLastY = -1; // save event y
	private Scroller mScroller; // used for scroll back
	private OnScrollListener mScrollListener; // user's scroll listener

	// the interface to trigger refresh and load more.
	private IXListViewListener mListViewListener;

	// -- header view
	private XListViewHeader mHeaderView;
	// header view content, use it to calculate the Header's height. And hide it
	// when disable pull refresh.
	private RelativeLayout mHeaderViewContent;
	private TextView mHeaderTimeView;
	private int mHeaderViewHeight; // header view's height
	private boolean mEnablePullRefresh = true;
	private boolean mPullRefreshing = false; // is refreashing.

	// -- footer view
	private XListViewFooter mFooterView;
	private boolean mEnablePullLoad;
	private boolean mPullLoading;
	private boolean mIsFooterReady = false;

	// total list items, used to detect is at the bottom of listview.
	private int mTotalItemCount;

	// for mScroller, scroll back from header or footer.
	private int mScrollBack;
	private final static int SCROLLBACK_HEADER = 0;
	private final static int SCROLLBACK_FOOTER = 1;

	private final static int SCROLL_DURATION = 400; // scroll back duration
	private final static int PULL_LOAD_MORE_DELTA = 50; // when pull up >= 50px
														// at bottom, trigger
														// load more.
	private final static float OFFSET_RADIO = 1.8f; // support iOS like pull
													// feature.

	/**
	 * @param context
	 */
	public XListView(Context context) {
		super(context);
		initWithContext(context);
	}

	public XListView(Context context, AttributeSet attrs) {
		super(context, attrs);
		initWithContext(context);
	}

	public XListView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		initWithContext(context);
	}

	private void initWithContext(Context context) {
		mScroller = new Scroller(context, new DecelerateInterpolator());
		// XListView need the scroll event, and it will dispatch the event to
		// user's listener (as a proxy).
		super.setOnScrollListener(this);

		// init header view
		mHeaderView = new XListViewHeader(context);
		mHeaderViewContent = (RelativeLayout) mHeaderView
				.findViewById(R.id.xlistview_header_content);
		mHeaderTimeView = (TextView) mHeaderView
				.findViewById(R.id.xlistview_header_time);
		addHeaderView(mHeaderView);

		// init footer view
		mFooterView = new XListViewFooter(context);

		// init header height
		mHeaderView.getViewTreeObserver().addOnGlobalLayoutListener(
				new OnGlobalLayoutListener() {
					@Override
					public void onGlobalLayout() {
						mHeaderViewHeight = mHeaderViewContent.getHeight();
						getViewTreeObserver()
								.removeGlobalOnLayoutListener(this);
					}
				});
	}

	@Override
	public void setAdapter(ListAdapter adapter) {
		// make sure XListViewFooter is the last footer view, and only add once.
		if (mIsFooterReady == false) {
			mIsFooterReady = true;
			addFooterView(mFooterView);
		}
		super.setAdapter(adapter);
	}

	/**
	 * enable or disable pull down refresh feature.
	 *
	 * @param enable
	 */
	public void setPullRefreshEnable(boolean enable) {
		mEnablePullRefresh = enable;
		if (!mEnablePullRefresh) { // disable, hide the content
			mHeaderViewContent.setVisibility(View.INVISIBLE);
		} else {
			mHeaderViewContent.setVisibility(View.VISIBLE);
		}
	}

	/**
	 * enable or disable pull up load more feature.
	 *
	 * @param enable
	 */
	public void setPullLoadEnable(boolean enable) {
		mEnablePullLoad = enable;
		if (!mEnablePullLoad) {
			mFooterView.hide();
			mFooterView.setOnClickListener(null);
			//make sure "pull up" don't show a line in bottom when listview with one page
			setFooterDividersEnabled(false);
		} else {
			mPullLoading = false;
			mFooterView.show();
			mFooterView.setState(XListViewFooter.STATE_NORMAL);
			//make sure "pull up" don't show a line in bottom when listview with one page
			setFooterDividersEnabled(true);
			// both "pull up" and "click" will invoke load more.
			mFooterView.setOnClickListener(new OnClickListener() {
				@Override
				public void onClick(View v) {
					startLoadMore();
				}
			});
		}
	}

	/**
	 * stop refresh, reset header view.
	 */
	public void stopRefresh() {
		if (mPullRefreshing == true) {
			mPullRefreshing = false;
			resetHeaderHeight();
		}
	}

	/**
	 * stop load more, reset footer view.
	 */
	public void stopLoadMore() {
		if (mPullLoading == true) {
			mPullLoading = false;
			mFooterView.setState(XListViewFooter.STATE_NORMAL);
		}
	}

	/**
	 * set last refresh time
	 *
	 * @param time
	 */
	public void setRefreshTime(String time) {
		mHeaderTimeView.setText(time);
	}

	private void invokeOnScrolling() {
		if (mScrollListener instanceof OnXScrollListener) {
			OnXScrollListener l = (OnXScrollListener) mScrollListener;
			l.onXScrolling(this);
		}
	}

	private void updateHeaderHeight(float delta) {
		mHeaderView.setVisiableHeight((int) delta
				+ mHeaderView.getVisiableHeight());
		if (mEnablePullRefresh && !mPullRefreshing) { // 鏈浜庡埛鏂扮姸鎬侊紝鏇存柊绠ご
			if (mHeaderView.getVisiableHeight() > mHeaderViewHeight) {
				mHeaderView.setState(XListViewHeader.STATE_READY);
			} else {
				mHeaderView.setState(XListViewHeader.STATE_NORMAL);
			}
		}
		setSelection(0); // scroll to top each time
	}

	/**
	 * reset header view's height.
	 */
	private void resetHeaderHeight() {
		int height = mHeaderView.getVisiableHeight();
		if (height == 0) // not visible.
			return;
		// refreshing and header isn't shown fully. do nothing.
		if (mPullRefreshing && height <= mHeaderViewHeight) {
			return;
		}
		int finalHeight = 0; // default: scroll back to dismiss header.
		// is refreshing, just scroll back to show all the header.
		if (mPullRefreshing && height > mHeaderViewHeight) {
			finalHeight = mHeaderViewHeight;
		}
		mScrollBack = SCROLLBACK_HEADER;
		mScroller.startScroll(0, height, 0, finalHeight - height,
				SCROLL_DURATION);
		// trigger computeScroll
		invalidate();
	}

	private void updateFooterHeight(float delta) {
		int height = mFooterView.getBottomMargin() + (int) delta;
		if (mEnablePullLoad && !mPullLoading) {
			if (height > PULL_LOAD_MORE_DELTA) { // height enough to invoke load
													// more.
				mFooterView.setState(XListViewFooter.STATE_READY);
			} else {
				mFooterView.setState(XListViewFooter.STATE_NORMAL);
			}
		}
		mFooterView.setBottomMargin(height);

//		setSelection(mTotalItemCount - 1); // scroll to bottom
	}

	private void resetFooterHeight() {
		int bottomMargin = mFooterView.getBottomMargin();
		if (bottomMargin > 0) {
			mScrollBack = SCROLLBACK_FOOTER;
			mScroller.startScroll(0, bottomMargin, 0, -bottomMargin,
					SCROLL_DURATION);
			invalidate();
		}
	}

	private void startLoadMore() {
		mPullLoading = true;
		mFooterView.setState(XListViewFooter.STATE_LOADING);
		if (mListViewListener != null) {
			mListViewListener.onLoadMore();
		}
	}

	@Override
	public boolean onTouchEvent(MotionEvent ev) {
		if (mLastY == -1) {
			mLastY = ev.getRawY();
		}

		switch (ev.getAction()) {
		case MotionEvent.ACTION_DOWN:
			mLastY = ev.getRawY();
			break;
		case MotionEvent.ACTION_MOVE:
			final float deltaY = ev.getRawY() - mLastY;
			mLastY = ev.getRawY();
			if (getFirstVisiblePosition() == 0
					&& (mHeaderView.getVisiableHeight() > 0 || deltaY > 0)) {
				// the first item is showing, header has shown or pull down.
				updateHeaderHeight(deltaY / OFFSET_RADIO);
				invokeOnScrolling();
			} else if (getLastVisiblePosition() == mTotalItemCount - 1
					&& (mFooterView.getBottomMargin() > 0 || deltaY < 0)) {
				// last item, already pulled up or want to pull up.
				updateFooterHeight(-deltaY / OFFSET_RADIO);
			}
			break;
		default:
			mLastY = -1; // reset
			if (getFirstVisiblePosition() == 0) {
				// invoke refresh
				if (mEnablePullRefresh
						&& mHeaderView.getVisiableHeight() > mHeaderViewHeight) {
					mPullRefreshing = true;
					mHeaderView.setState(XListViewHeader.STATE_REFRESHING);
					if (mListViewListener != null) {
						mListViewListener.onRefresh();
					}
				}
				resetHeaderHeight();
			} else if (getLastVisiblePosition() == mTotalItemCount - 1) {
				// invoke load more.
				if (mEnablePullLoad
				    && mFooterView.getBottomMargin() > PULL_LOAD_MORE_DELTA
				    && !mPullLoading) {
					startLoadMore();
				}
				resetFooterHeight();
			}
			break;
		}
		return super.onTouchEvent(ev);
	}

	@Override
	public void computeScroll() {
		if (mScroller.computeScrollOffset()) {
			if (mScrollBack == SCROLLBACK_HEADER) {
				mHeaderView.setVisiableHeight(mScroller.getCurrY());
			} else {
				mFooterView.setBottomMargin(mScroller.getCurrY());
			}
			postInvalidate();
			invokeOnScrolling();
		}
		super.computeScroll();
	}

	@Override
	public void setOnScrollListener(OnScrollListener l) {
		mScrollListener = l;
	}

	@Override
	public void onScrollStateChanged(AbsListView view, int scrollState) {
		if (mScrollListener != null) {
			mScrollListener.onScrollStateChanged(view, scrollState);
		}
	}

	@Override
	public void onScroll(AbsListView view, int firstVisibleItem,
			int visibleItemCount, int totalItemCount) {
		// send to user's listener
		mTotalItemCount = totalItemCount;
		if (mScrollListener != null) {
			mScrollListener.onScroll(view, firstVisibleItem, visibleItemCount,
					totalItemCount);
		}
	}

	public void setXListViewListener(IXListViewListener l) {
		mListViewListener = l;
	}

	/**
	 * you can listen ListView.OnScrollListener or this one. it will invoke
	 * onXScrolling when header/footer scroll back.
	 */
	public interface OnXScrollListener extends OnScrollListener {
		public void onXScrolling(View view);
	}

	/**
	 * implements this interface to get refresh/load more event.
	 */
	public interface IXListViewListener {
		public void onRefresh();

		public void onLoadMore();
	}
}

XListViewActivity类；主要学习这个类；调用其他的类就ok

package me.maxwin;

import java.util.ArrayList;

import me.maxwin.view.XListView;
import me.maxwin.view.XListView.IXListViewListener;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.widget.ArrayAdapter;

public class XListViewActivity extends Activity implements IXListViewListener {
	private XListView mListView;
	private ArrayAdapter<String> mAdapter;
	private ArrayList<String> items = new ArrayList<String>();
	private Handler mHandler;
	private int start = 0;
	private static int refreshCnt = 0;
	/** Called when the activity is first created. */
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		geneItems();
		mListView = (XListView) findViewById(R.id.xListView);
		mListView.setPullLoadEnable(true);
		mAdapter = new ArrayAdapter<String>(this, R.layout.list_item, items);
		mListView.setAdapter(mAdapter);
//		mListView.setPullLoadEnable(false);
//		mListView.setPullRefreshEnable(false);
		mListView.setXListViewListener(this);
		mHandler = new Handler();
	}

	private void geneItems() {
		for (int i = 0; i != 20; ++i) {
			items.add("refresh cnt " + (++start));
		}
	}

	private void onLoad() {
		mListView.stopRefresh();
		mListView.stopLoadMore();
		mListView.setRefreshTime("鍒氬垰");
	}

	@Override
	public void onRefresh() {
		mHandler.postDelayed(new Runnable() {
			@Override
			public void run() {
				start = ++refreshCnt;
				items.clear();
				geneItems();
				// mAdapter.notifyDataSetChanged();
				mAdapter = new ArrayAdapter<String>(XListViewActivity.this, R.layout.list_item, items);
				mListView.setAdapter(mAdapter);
				onLoad();
			}
		}, 2000);
	}

	@Override
	public void onLoadMore() {
		mHandler.postDelayed(new Runnable() {
			@Override
			public void run() {
				geneItems();
				mAdapter.notifyDataSetChanged();
				onLoad();
			}
		}, 2000);
	}

}

layout文件源码

<?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="fill_parent"
    android:orientation="vertical" android:background="#f0f0f0">

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello" />

    <me.maxwin.view.XListView
        android:id="@+id/xListView"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" android:cacheColorHint="#00000000">
    </me.maxwin.view.XListView>

</LinearLayout>

效果运行了就知道啦；哈哈；