ListView下拉刷新，上拉加载

代码结构，主要是两个类，实现头部功能的封装，写出一个自定义控件

1、头部封装类

/**

 * 该类主要是完成 头部部分的功能封装

 * 

 * 一个可以监听ListView是否滚动到最顶部或最底部的自定义控件 只能监听由触摸产生的，如果是ListView本身Flying导致的，则不能监听</br>

 * 如果加以改进，可以实现监听scroll滚动的具体位置等

 * 

 * @author 进

 */

public class ScrollOverListView extends ListView implements OnScrollListener {

private int mLastY;

private int mBottomPosition;

private static final String TAG = "listview";

/** 松开更新 **/

private final static int RELEASE_To_REFRESH = 0;

/** 下拉更新 **/

private final static int PULL_To_REFRESH = 1;

/** 更新中 **/

private final static int REFRESHING = 2;

/** 无 **/

private final static int DONE = 3;

/** 加载中 **/

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;

/** 头部刷新的布局 **/

private LinearLayout headView;

/** 头部显示下拉刷新等的控件 **/

private TextView tipsTextview;

/** 刷新控件 **/

private TextView lastUpdatedTextView;

/** 箭头图标 **/

private ImageView arrowImageView;

/** 头部滚动条 **/

private ProgressBar progressBar;

/** 显示动画 **/

private RotateAnimation animation;

/** 头部回退显示动画 **/

private RotateAnimation reverseAnimation;

/** 用于保证startY的值在一个完整的touch事件中只被记录一次 **/

private boolean isRecored;

/** 头部高度 **/

private int headContentHeight;

/** 开始的Y坐标 **/

private int startY;

/** 第一个item **/

private int firstItemIndex;

/** 状态 **/

private int state;

private boolean isBack;

/** 是否要使用下拉刷新功能 **/

public boolean showRefresh = true;

public static boolean canRefleash = true;

public ScrollOverListView(Context context, AttributeSet attrs, int defStyle) {

super(context, attrs, defStyle);

init(context);

}

public ScrollOverListView(Context context, AttributeSet attrs) {

super(context, attrs);

init(context);

}

public ScrollOverListView(Context context) {

super(context);

init(context);

}

/** 出事化控件 **/

private void init(Context context) {

mBottomPosition = 0;

setCacheColorHint(0);

inflater = LayoutInflater.from(context);

headView = (LinearLayout) inflater.inflate(R.layout.pull_down_head,

null);

arrowImageView = (ImageView) headView

.findViewById(R.id.head_arrowImageView);

arrowImageView.setMinimumWidth(70);

arrowImageView.setMinimumHeight(50);

progressBar = (ProgressBar) headView

.findViewById(R.id.head_progressBar);

tipsTextview = (TextView) headView.findViewById(R.id.head_tipsTextView);

lastUpdatedTextView = (TextView) headView

.findViewById(R.id.head_lastUpdatedTextView);

measureView(headView);

headContentHeight = headView.getMeasuredHeight();

headView.setPadding(0, -1 * headContentHeight, 0, 0);

headView.invalidate();

/** 列表添加头部 **/

addHeaderView(headView, null, false);

setOnScrollListener(this);

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);

state = DONE;

}

/** 触摸事件的处理 **/

@Override

public boolean onTouchEvent(MotionEvent ev) {

final int action = ev.getAction();

final int y = (int) ev.getRawY();

cancelLongPress();

switch (action) {

case MotionEvent.ACTION_DOWN: { // 按下的时候

if (firstItemIndex == 0 && !isRecored) {

isRecored = true;

startY = (int) ev.getY();

}

mLastY = y;

final boolean isHandled = mOnScrollOverListener.onMotionDown(ev);

if (isHandled) {

mLastY = y;

return isHandled;

}

break;

}

case MotionEvent.ACTION_MOVE: { // 手指正在移动的时候

int tempY = (int) ev.getY();

if (showRefresh) {

if (!isRecored && firstItemIndex == 0) {

Log.v(TAG, "在move时候记录下位置");

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，否则如果当列表超出屏幕的话，当在上推的时候，列表会同时进行滚动

// 可以松手去刷新了

if (state == RELEASE_To_REFRESH) {

setSelection(0);

// 往上推了，推到了屏幕足够掩盖head的程度，但是还没有推到全部掩盖的地步

if (((tempY - startY) / RATIO < headContentHeight)

&& (tempY - startY) > 0) {

state = PULL_To_REFRESH;

changeHeaderViewByState();

}

// 一下子推到顶了

else if (tempY - startY <= 0) {

state = DONE;

changeHeaderViewByState();

}

// 往下拉了，或者还没有上推到屏幕顶部掩盖head的地步

else {

// 不用进行特别的操作，只用更新paddingTop的值就行了

}

}

// 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);

// 下拉到可以进入RELEASE_TO_REFRESH的状态

if ((tempY - startY) / RATIO >= headContentHeight) {

state = RELEASE_To_REFRESH;

isBack = true;

changeHeaderViewByState();

}

// 上推到顶了

else if (tempY - startY <= 0) {

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) {

headView.setPadding(0, -1 * headContentHeight

+ (tempY - startY) / RATIO, 0, 0);

}

// 更新headView的paddingTop

if (state == RELEASE_To_REFRESH) {

headView.setPadding(0, (tempY - startY) / RATIO

- headContentHeight, 0, 0);

}

}

}

final int childCount = getChildCount();

if (childCount == 0)

return super.onTouchEvent(ev);

final int itemCount = getAdapter().getCount() - mBottomPosition;

final int deltaY = y - mLastY;

final int lastBottom = getChildAt(childCount - 1).getBottom();

final int end = getHeight() - getPaddingBottom();

final int firstVisiblePosition = getFirstVisiblePosition();

final boolean isHandleMotionMove = mOnScrollOverListener

.onMotionMove(ev, deltaY);

if (isHandleMotionMove) {

mLastY = y;

return true;

}

/** 到达底部 * 到达底部的事件在另外一个类执行 **/

if (firstVisiblePosition + childCount >= itemCount

&& lastBottom <= end && deltaY < 0) {

final boolean isHandleOnListViewBottomAndPullDown;

isHandleOnListViewBottomAndPullDown = mOnScrollOverListener

.onListViewBottomAndPullUp(deltaY);

if (isHandleOnListViewBottomAndPullDown) {

mLastY = y;

return true;

}

}

break;

}

case MotionEvent.ACTION_UP: { // 手指抬起来的时候

if (state != REFRESHING && state != LOADING) {

if (state == DONE) {

// 什么都不做

}

if (state == PULL_To_REFRESH) {

state = DONE;

changeHeaderViewByState();

}

if (state == RELEASE_To_REFRESH) {

state = REFRESHING;

changeHeaderViewByState();

canRefleash = true;

}

}

isRecored = false;

isBack = false;

// /======================

final boolean isHandlerMotionUp = mOnScrollOverListener

.onMotionUp(ev);

if (isHandlerMotionUp) {

mLastY = y;

return true;

}

break;

}

}

mLastY = y;

return super.onTouchEvent(ev);

}

/** 空的 */

private OnScrollOverListener mOnScrollOverListener = new OnScrollOverListener() {

@Override

public boolean onListViewTopAndPullDown(int delta) {

return false;

}

@Override

public boolean onListViewBottomAndPullUp(int delta) {

return false;

}

@Override

public boolean onMotionDown(MotionEvent ev) {

return false;

}

@Override

public boolean onMotionMove(MotionEvent ev, int delta) {

return false;

}

@Override

public boolean onMotionUp(MotionEvent ev) {

return false;

}

};

// =============================== public method

/**

 * 可以自定义其中一个条目为头部，头部触发的事件将以这个为准，默认为第一个

 * 

 * @param index

 *            正数第几个，必须在条目数范围之内

 */

public void setTopPosition(int index) {

if (getAdapter() == null)

throw new NullPointerException(

"You must set adapter before setTopPosition!");

if (index < 0)

throw new IllegalArgumentException("Top position must > 0");

}

/**

 * 可以自定义其中一个条目为尾部，尾部触发的事件将以这个为准，默认为最后一个

 * 

 * @param index

 *            倒数第几个，必须在条目数范围之内

 */

public void setBottomPosition(int index) {

if (getAdapter() == null)

throw new NullPointerException(

"You must set adapter before setBottonPosition!");

if (index < 0)

throw new IllegalArgumentException("Bottom position must > 0");

mBottomPosition = index;

}

/**

 * 设置这个Listener可以监听是否到达顶端，或者是否到达低端等事件</br>

 * 

 * @see OnScrollOverListener

 */

public void setOnScrollOverListener(

OnScrollOverListener onScrollOverListener) {

mOnScrollOverListener = onScrollOverListener;

}

/**

 * 滚动监听接口

 * 

 * @see ScrollOverListView#setOnScrollOverListener(OnScrollOverListener)

 * 

 */

public interface OnScrollOverListener {

/**

 * 到达最顶部触发

 * 

 * @param delta

 *            手指点击移动产生的偏移量

 * @return

 */

boolean onListViewTopAndPullDown(int delta);

/**

 * 到达最底部触发

 * 

 * @param delta

 *            手指点击移动产生的偏移量

 * @return

 */

boolean onListViewBottomAndPullUp(int delta);

/**

 * 手指触摸按下触发，相当于{@link MotionEvent#ACTION_DOWN}

 * 

 * @return 返回true表示自己处理

 * @see View#onTouchEvent(MotionEvent)

 */

boolean onMotionDown(MotionEvent ev);

/**

 * 手指触摸移动触发，相当于{@link MotionEvent#ACTION_MOVE}

 * 

 * @return 返回true表示自己处理

 * @see View#onTouchEvent(MotionEvent)

 */

boolean onMotionMove(MotionEvent ev, int delta);

/**

 * 手指触摸后提起触发，相当于{@link MotionEvent#ACTION_UP}

 * 

 * @return 返回true表示自己处理

 * @see View#onTouchEvent(MotionEvent)

 */

boolean onMotionUp(MotionEvent ev);

}

@Override

public void onScroll(AbsListView arg0, int firstVisiableItem, int arg2,

int arg3) {

firstItemIndex = firstVisiableItem;

}

@Override

public void onScrollStateChanged(AbsListView view, int scrollState) {

}

// 此方法直接照搬自网络上的一个下拉刷新的demo，此处是“估计”headView的width以及height

private void measureView(View child) {

ViewGroup.LayoutParams p = child.getLayoutParams();

if (p == null) {

p = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.FILL_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);

}

public void onRefreshComplete() {

state = DONE;

// 头部更新时候的操作，显示当前系统进行更新的时间

lastUpdatedTextView.setText("最近更新:" + new Date().toLocaleString());

changeHeaderViewByState();

}

// 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:

arrowImageView.setVisibility(View.VISIBLE);

progressBar.setVisibility(View.GONE);

tipsTextview.setVisibility(View.VISIBLE);

lastUpdatedTextView.setVisibility(View.VISIBLE);

arrowImageView.clearAnimation();

arrowImageView.startAnimation(animation);

tipsTextview.setText("松开刷新");

break;

case PULL_To_REFRESH:

progressBar.setVisibility(View.GONE);

tipsTextview.setVisibility(View.VISIBLE);

lastUpdatedTextView.setVisibility(View.VISIBLE);

arrowImageView.clearAnimation();

arrowImageView.setVisibility(View.VISIBLE);

// 是由RELEASE_To_REFRESH状态转变来的

if (isBack) {

isBack = false;

arrowImageView.clearAnimation();

arrowImageView.startAnimation(reverseAnimation);

tipsTextview.setText("下拉刷新");

} else {

tipsTextview.setText("下拉刷新");

}

break;

case REFRESHING:

headView.setPadding(0, 0, 0, 0);

progressBar.setVisibility(View.VISIBLE);

arrowImageView.clearAnimation();

arrowImageView.setVisibility(View.GONE);

tipsTextview.setText("正在刷新...");

lastUpdatedTextView.setVisibility(View.VISIBLE);

break;

case DONE:

headView.setPadding(0, -1 * headContentHeight, 0, 0);

progressBar.setVisibility(View.GONE);

arrowImageView.clearAnimation();

arrowImageView.setImageResource(R.drawable.pull_down_arrow);

tipsTextview.setText("下拉刷新");

lastUpdatedTextView.setVisibility(View.VISIBLE);

break;

}

}

}

2、要写个自定义控件把这个给加载进去

/**

 * 下拉刷新控件   真正实现下拉刷新的是这个控件， ScrollOverListView只是提供触摸的事件等

 * 

 * @author 

 */

public class PullDownView extends LinearLayout implements OnScrollOverListener {

private static final int START_PULL_DEVIATION = 50; /** 移动误差*/

private static final int WHAT_DID_MORE = 5; /** Handler what 已经获取完更多*/

private static final int WHAT_DID_REFRESH = 3; /** Handler what 已经刷新完*/

/**底部更多的按键**/

private RelativeLayout mFooterView;

/**底部更多的按键**/

private TextView mFooterTextView;

/**底部更多的按键**/

private ProgressBar mFooterLoadingView;

/**已经含有 下拉刷新功能的列表**/

private ScrollOverListView mListView;

/**刷新和更多的事件接口**/

private OnPullDownListener mOnPullDownListener;

private float mMotionDownLastY; /** 按下时候的Y轴坐标*/

private boolean mIsFetchMoreing; /** 是否获取更多中*/

private boolean mIsPullUpDone; /** 是否回推完成*/

private boolean mEnableAutoFetchMore; /** 是否允许自动获取更多*/

public PullDownView(Context context, AttributeSet attrs) {

super(context, attrs);

initHeaderViewAndFooterViewAndListView(context);

}

public PullDownView(Context context) {

super(context);

initHeaderViewAndFooterViewAndListView(context);

}

/*

 * ================================== Public method 外部使用，具体就是用这几个就可以了

 */

/**

 * 刷新和获取更多事件接口

 */

public interface OnPullDownListener {

/**刷新事件接口  这里要注意的是获取更多完 要关闭 刷新的进度条RefreshComplete()**/

void onRefresh();

/**刷新事件接口  这里要注意的是获取更多完 要关闭 更多的进度条 notifyDidMore()**/

void onMore();

}

/**

 * 通知已经获取完更多了，要放在Adapter.notifyDataSetChanged后面

 * 当你执行完更多任务之后，调用这个notyfyDidMore() 才会隐藏加载圈等操作

 */

public void notifyDidMore() {

mUIHandler.sendEmptyMessage(WHAT_DID_MORE);

}

/** 刷新完毕 关闭头部滚动条 **/

public void RefreshComplete() {

mUIHandler.sendEmptyMessage(WHAT_DID_REFRESH);

}

/**

 * 设置监听器

 * 

 * @param listener

 */

public void setOnPullDownListener(OnPullDownListener listener) {

mOnPullDownListener = listener;

}

/**

 * 获取内嵌的listview

 * 

 * @return ScrollOverListView

 */

public ListView getListView() {

return mListView;

}

/**

 * 是否开启自动获取更多 自动获取更多，将会隐藏footer，并在到达底部的时候自动刷新

 * 

 * @param index

 *            倒数第几个触发

 */

public void enableAutoFetchMore(boolean enable, int index) {

if (enable) {

mListView.setBottomPosition(index);

mFooterLoadingView.setVisibility(View.GONE);

} else {

mFooterTextView.setText("数据加载完毕");

mFooterLoadingView.setVisibility(View.GONE);

}

mEnableAutoFetchMore = enable;

}

/**

 * Private method 具体实现下拉刷新等操作

 */

/**

 * 初始化界面

 */

private void initHeaderViewAndFooterViewAndListView(Context context) {

setOrientation(LinearLayout.VERTICAL);

/**

 * 自定义脚部文件

 */

mFooterView = (RelativeLayout) LayoutInflater.from(context).inflate(

R.layout.pulldown_footer, null);

mFooterTextView = (TextView) mFooterView

.findViewById(R.id.pulldown_footer_text);

mFooterLoadingView = (ProgressBar) mFooterView

.findViewById(R.id.pulldown_footer_loading);

// mFooterView.setOnClickListener(new OnClickListener() {

// @Override

// public void onClick(View v) {

// if (!mIsFetchMoreing) {

//

// mIsFetchMoreing = true;

// mFooterTextView.setText("加载更多中...");

// mFooterLoadingView.setVisibility(View.VISIBLE);

// mOnPullDownListener.onMore();

// }

// }

// });

/**

 * ScrollOverListView 同样是考虑到都是使用，所以放在这里 同时因为，需要它的监听事件

 */

mListView = new ScrollOverListView(context);

mListView.setOnScrollOverListener(this);

mListView.setCacheColorHint(0);

addView(mListView, LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);

// 空的listener

mOnPullDownListener = new OnPullDownListener() {

@Override

public void onRefresh() {

}

@Override

public void onMore() {

}

};

mListView.addFooterView(mFooterView);

mListView.setFooterDividersEnabled(false);

//mListView.setAdapter(mListView.getAdapter());

}

private Handler mUIHandler = new Handler() {

@Override

public void handleMessage(Message msg) {

switch (msg.what) {

case WHAT_DID_REFRESH: {

mListView.onRefreshComplete();

return;

}

case WHAT_DID_MORE: {

mIsFetchMoreing = false;

mFooterTextView.setText("加载更多");

mFooterLoadingView.setVisibility(View.GONE);

}

}

}

};

/**

 * 条目是否填满整个屏幕

 */

private boolean isFillScreenItem() {

final int firstVisiblePosition = mListView.getFirstVisiblePosition();

final int lastVisiblePostion = mListView.getLastVisiblePosition()

- mListView.getFooterViewsCount();

final int visibleItemCount = lastVisiblePostion - firstVisiblePosition

+ 1;

final int totalItemCount = mListView.getCount()

- mListView.getFooterViewsCount();

if (visibleItemCount < totalItemCount)

return true;

return false;

}

/*

 * ================================== 实现 OnScrollOverListener接口

 */

@Override

public boolean onListViewTopAndPullDown(int delta) {

return true;

}

@Override

public boolean onListViewBottomAndPullUp(int delta) {

if (!mEnableAutoFetchMore || mIsFetchMoreing)

return false;

/** 数量充满屏幕才触发*/

if (isFillScreenItem()) {

mIsFetchMoreing = true;

mFooterTextView.setText("加载更多中...");

mFooterLoadingView.setVisibility(View.VISIBLE);

mOnPullDownListener.onMore();

return true;

}

return false;

}

@Override

public boolean onMotionDown(MotionEvent ev) {

mIsPullUpDone = false;

mMotionDownLastY = ev.getRawY();

return false;

}

@Override

public boolean onMotionMove(MotionEvent ev, int delta) {

/** 当头部文件回推消失的时候，不允许滚动*/

if (mIsPullUpDone)

return true;

/** 如果开始按下到滑动距离不超过误差值，则不滑动*/

final int absMotionY = (int) Math.abs(ev.getRawY() - mMotionDownLastY);

if (absMotionY < START_PULL_DEVIATION)

return true;

return false;

}

@Override

public boolean onMotionUp(MotionEvent ev) {

if (ScrollOverListView.canRefleash) {

ScrollOverListView.canRefleash = false;

mOnPullDownListener.onRefresh();

}

return false;

}

/**隐藏头部 禁用下拉更新**/

public void setHideHeader() {

mListView.showRefresh = false;

}

/**显示头部 使用下拉更新**/

public void setShowHeader() {

mListView.showRefresh = true;

}

/**隐藏底部 禁用上拉更多**/

public void setHideFooter() {

mFooterView.setVisibility(View.GONE);

mFooterTextView.setVisibility(View.GONE);

mFooterLoadingView.setVisibility(View.GONE);

enableAutoFetchMore(false, 1);

}

/**显示底部 使用上拉更多**/

public void setShowFooter() {

mFooterView.setVisibility(View.VISIBLE);

mFooterTextView.setVisibility(View.VISIBLE);

mFooterLoadingView.setVisibility(View.VISIBLE);

enableAutoFetchMore(true, 1);

}

}

3、实际操作

代码实例：

/**

 * 下拉刷新上拉更多

 * 

 * @author

 */

public class PullDownActivity extends Activity implements OnPullDownListener,

OnItemClickListener {

/** Handler What加载数据完毕 **/

private static final int WHAT_DID_LOAD_DATA = 0;

/** Handler What更新数据完毕 **/

private static final int WHAT_DID_REFRESH = 1;

/** Handler What更多数据完毕 **/

private static final int WHAT_DID_MORE = 2;

private ListView mListView;

private ArrayAdapter<String> mAdapter;

private PullDownView mPullDownView;

private List<String> mStrings = new ArrayList<String>();

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.pulldown);

/**

 * 1.使用PullDownView 2.设置OnPullDownListener 3.从mPullDownView里面获取ListView

 */

mPullDownView = (PullDownView) findViewById(R.id.pull_down_view);

mPullDownView.setOnPullDownListener(this);

mListView = mPullDownView.getListView();

mListView.setOnItemClickListener(this);

mAdapter = new ArrayAdapter<String>(this, R.layout.pulldown_item,

mStrings);

mListView.setAdapter(mAdapter);

// 设置可以自动获取更多 滑到最后一个自动获取 改成false将禁用自动获取更多

mPullDownView.enableAutoFetchMore(true, 1);

// 隐藏 并禁用尾部

mPullDownView.setHideFooter();

// 显示并启用自动获取更多

mPullDownView.setShowFooter();

/** 隐藏并且禁用头部刷新*/

mPullDownView.setHideHeader();

/** 显示并且可以使用头部刷新*/

mPullDownView.setShowHeader();

/** 之前 网上很多代码 都会导致刷新事件 跟 上下文菜单同时弹出 这里做测试。。。已经解决 */

mListView

.setOnCreateContextMenuListener(new OnCreateContextMenuListener() {

@Override

public void onCreateContextMenu(ContextMenu menu, View v,

ContextMenuInfo menuInfo) {

}

});

// 加载数据 本类使用

loadData();

}

/** 刷新事件接口 这里要注意的是获取更多完 要关闭 刷新的进度条RefreshComplete() **/

@Override

public void onRefresh() {

new Thread(new Runnable() {

@Override

public void run() {

try {

Thread.sleep(2000);

} catch (InterruptedException e) {

e.printStackTrace();

}

/** 关闭 刷新完毕 ***/

mPullDownView.RefreshComplete();// 这个事线程安全的 可看源代码

// 这个地方有点疑问

Message msg = mUIHandler.obtainMessage(WHAT_DID_REFRESH);

msg.obj = "After refresh " + System.currentTimeMillis();

msg.sendToTarget();

}

}).start();

}

/** 刷新事件接口 这里要注意的是获取更多完 要关闭 更多的进度条 notifyDidMore() **/

@Override

public void onMore() {

new Thread(new Runnable() {

@Override

public void run() {

try {

Thread.sleep(2000);

} catch (InterruptedException e) {

e.printStackTrace();

}

// 告诉它获取更多完毕 这个事线程安全的 可看源代码

mPullDownView.notifyDidMore();

Message msg = mUIHandler.obtainMessage(WHAT_DID_MORE);

msg.obj = "After more " + System.currentTimeMillis();

msg.sendToTarget();

}

}).start();

}

private Handler mUIHandler = new Handler() {

@Override

public void handleMessage(Message msg) {

switch (msg.what) {

case WHAT_DID_LOAD_DATA: {

if (msg.obj != null) {

List<String> strings = (List<String>) msg.obj;

if (!strings.isEmpty()) {

mStrings.addAll(strings);

mAdapter.notifyDataSetChanged();

}

}

Toast.makeText(PullDownActivity.this,

"" + mListView.getAdapter().getCount(),

Toast.LENGTH_LONG).show();

// 诉它数据加载完毕;

break;

}

case WHAT_DID_REFRESH: {

String body = (String) msg.obj;

mStrings.add(0, body);

mAdapter.notifyDataSetChanged();

// 告诉它更新完毕

break;

}

case WHAT_DID_MORE: {

String body = (String) msg.obj;

mStrings.add(body);

mAdapter.notifyDataSetChanged();

break;

}

}

}

};

@Override

public void onItemClick(AdapterView<?> parent, View view, int position,

long id) {

Toast.makeText(this, "啊，你点中我了 " + position, Toast.LENGTH_SHORT).show();

}

// 模拟数据

private String[] mStringArray = { "Abbaye de Belloc"/*

 * ,

 * "Abbaye du Mont des Cats"

 * , "Abertam",

 * "Abondance",

 * "Ackawi", "Acorn",

 * "Adelost",

 * "Affidelice au Chablis"

 * , "Afuega'l Pitu",

 * "Airag", "Airedale",

 * "Aisy Cendre",

 * "Allgauer Emmentaler"

 * , "Alverca",

 * "Ambert",

 * "American Cheese"

 */};

private void loadData() {

new Thread(new Runnable() {

@Override

public void run() {

try {

Thread.sleep(0000);

} catch (InterruptedException e) {

e.printStackTrace();

}

List<String> strings = new ArrayList<String>();

for (String body : mStringArray) {

strings.add(body);

}

Message msg = mUIHandler.obtainMessage(WHAT_DID_LOAD_DATA);

msg.obj = strings;

msg.sendToTarget();

}

}).start();

}

}

4、零碎小东西

资源文件

pull_down_head.xml

<?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: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/head_arrowImageView"

                android:layout_width="wrap_content"

                android:layout_height="wrap_content"

                android:layout_gravity="center"

                android:src="@drawable/pull_down_arrow" />

            <!-- 进度条 -->

            <ProgressBar

                android:id="@+id/head_progressBar"

                style="?android:attr/progressBarStyleSmall"

                android:layout_width="wrap_content"

                android:layout_height="wrap_content"

                android:layout_gravity="center"

                android:visibility="gone" />

        </FrameLayout>

        <!-- 提示、最近更新 -->

        <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/head_tipsTextView"

                android:layout_width="wrap_content"

                android:layout_height="wrap_content"

                android:text="下拉刷新"

                android:textColor="#000000"

                android:textSize="20sp" />

            <!-- 最近更新 -->

            <TextView

                android:id="@+id/head_lastUpdatedTextView"

                android:layout_width="wrap_content"

                android:layout_height="wrap_content"

                android:text="上次更新"

                android:textColor="#000000"

                android:textSize="10sp" />

        </LinearLayout>

    </RelativeLayout>

</LinearLayout>

pull_down_footer.xml

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="fill_parent"

    android:layout_height="wrap_content"

    android:paddingBottom="10dp"

    android:paddingTop="10dp" >

    <TextView

        android:id="@+id/pulldown_footer_text"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_centerInParent="true"

        android:text="更多"

        android:textSize="15dp" />

    <ProgressBar

        android:id="@+id/pulldown_footer_loading"

        style="@android :style/Widget.ProgressBar.Small.Inverse"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:layout_centerVertical="true"

        android:layout_marginLeft="20dp"

        android:visibility="gone" />

</RelativeLayout>