編輯：關於Android編程
本文主要是貼出xlistview的源代碼和一個使用實例，沒有過多講解
使用實例，MainActivity
public class MainActivity extends Activity {
private LinkedList listItems = null;
private XListView listView = null;
private ArrayAdapter adapter;
private String[] mStrings = { Aaaaaa, Bbbbbb, Cccccc, Dddddd, Eeeeee,
Ffffff, Gggggg, Hhhhhh, Iiiiii, Jjjjjj, Kkkkkk, Llllll, Mmmmmm,
Nnnnnn, };
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (XListView)findViewById(R.id.mlist);
listView.setXListViewListener(new IXListViewListener() {
@Override
public void onRefresh() {
new GetDataTask(true).execute();
}
@Override
public void onLoadMore() {
new GetDataTask(false).execute();
}
});
listItems = new LinkedList();
listItems.addAll(Arrays.asList(mStrings));
adapter = new ArrayAdapter(this, android.R.layout.simple_list_item_1, listItems);
listView.setAdapter(adapter);
listView.setPullLoadEnable(true);
}
private class GetDataTask extends AsyncTask {
private boolean isDropDown;
public GetDataTask(boolean isDropDown){
this.isDropDown = isDropDown;
}
@Override
protected String[] doInBackground(Void... params) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
;
}
return mStrings;
}
@Override
protected void onPostExecute(String[] result) {
if (isDropDown) {
listItems.addFirst(Added after drop down);
adapter.notifyDataSetChanged();
listView.stopRefresh();
} else {
listItems.add(Added after on bottom);
adapter.notifyDataSetChanged();
listView.stopLoadMore();
}
super.onPostExecute(result);
}
}
}
public class XListView extends ListView implements OnScrollListener {
private float mLastY = -1; // save event y
/**
* 用於下拉後，滑動返回
*/
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;
/**
* 下拉頭部
*/
private XListViewHeader mHeaderView;
/**
* 下拉頭主體，用於計算頭部的高度
* 當不能刷新時，被隱藏
*/
private RelativeLayout mHeaderViewContent;
/**
* 下拉箭頭
*/
private TextView mHeaderTimeView;
/**
* 下拉頭部的高度
*/
private int mHeaderViewHeight;
/**
* 能否下拉刷新
*/
private boolean mEnablePullRefresh = true;
/**
* 是否正在刷新,false表示正在刷新
*/
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;
/**
* 頭部滑動返回
*/
private final static int SCROLLBACK_HEADER = 0;
/**
* footer滑動返回
*/
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);
//初始化下拉頭
mHeaderView = new XListViewHeader(context);
mHeaderViewContent = (RelativeLayout) mHeaderView
.findViewById(R.id.xlistview_header_content);
mHeaderTimeView = (TextView) mHeaderView
.findViewById(R.id.xlistview_header_time);
addHeaderView(mHeaderView);
//初始化底部
mFooterView = new XListViewFooter(context);
//初始化下拉頭高度
mHeaderView.getViewTreeObserver().addOnGlobalLayoutListener(
new OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
mHeaderViewHeight = mHeaderViewContent.getHeight();//獲得下拉頭的高度
getViewTreeObserver()
.removeGlobalOnLayoutListener(this);
}
});
}
@Override
public void setAdapter(ListAdapter adapter) {
/*
* 將上拉加載更多footer加入listview的底部
* 並且保證只加入一次
*/
if (mIsFooterReady == false) {
mIsFooterReady = true;
addFooterView(mFooterView);//listview原生方法
}
super.setAdapter(adapter);
}
/**
* 設置下拉刷新功能是否開啟
* @param enable
*/
public void setPullRefreshEnable(boolean enable) {
mEnablePullRefresh = enable;
if (!mEnablePullRefresh) {//不開啟，隱藏頭部
mHeaderViewContent.setVisibility(View.INVISIBLE);
} else {
mHeaderViewContent.setVisibility(View.VISIBLE);
}
}
/**
* 設置上拉加載更多功能是否開啟
* 如果要開啟，必須主動調用這個函數
* @param enable
*/
public void setPullLoadEnable(boolean enable) {
mEnablePullLoad = enable;
if (!mEnablePullLoad) {//如果不開啟
mFooterView.hide();//隱藏footer
mFooterView.setOnClickListener(null);//取消監聽
//make sure pull up don't show a line in bottom when listview with one page
//保證listview的item之間的分割線消失(最後一條)
setFooterDividersEnabled(false);//listview原生方法
} 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.
* 停止刷新，重置頭部
*/
public void stopRefresh() {
if (mPullRefreshing == true) {
mPullRefreshing = false;
resetHeaderHeight();
}
}
/**
* stop load more, reset footer view.
* 停止加載更多，重置footer
*/
public void stopLoadMore() {
if (mPullLoading == true) {
mPullLoading = false;
mFooterView.setState(XListViewFooter.STATE_NORMAL);
}
}
/**
* set last refresh time
* 設置最後一次下來刷新時間
* @param time
*/
public void setRefreshTime(String time) {
mHeaderTimeView.setText(time);
}
private void invokeOnScrolling() {
if (mScrollListener instanceof OnXScrollListener) {
OnXScrollListener l = (OnXScrollListener) mScrollListener;
l.onXScrolling(this);
}
}
/**
* 更新頭部高度
* 這個函數用於下拉時，記錄下拉了多少
* @param delta
*/
private void updateHeaderHeight(float delta) {
mHeaderView.setVisiableHeight((int) delta
+ mHeaderView.getVisiableHeight());
if (mEnablePullRefresh && !mPullRefreshing) {//未處於刷新狀態，更新箭頭
if (mHeaderView.getVisiableHeight() > mHeaderViewHeight) {
mHeaderView.setState(XListViewHeader.STATE_READY);
} else {
mHeaderView.setState(XListViewHeader.STATE_NORMAL);
}
}
//滑動到頭部
setSelection(0); // scroll to top each time
}
/**
* reset header view's height.
* 重置頭部高度
*/
private void resetHeaderHeight() {
int height = mHeaderView.getVisiableHeight();
if (height == 0) // not visible.
return;
// refreshing and header isn't shown fully. do nothing.
//正在刷新，或者頭部沒有完全顯示，返回
if (mPullRefreshing && height <= mHeaderViewHeight) {
return;
}
int finalHeight = 0; // 默認最終高度，也就是說要讓頭部消失
// is refreshing, just scroll back to show all the header.
//正在刷新，並且下拉頭部完全顯示
if (mPullRefreshing && height > mHeaderViewHeight) {
finalHeight = mHeaderViewHeight;
}
mScrollBack = SCROLLBACK_HEADER;
//從當前位置，返回到頭部被隱藏
mScroller.startScroll(0, height, 0, finalHeight - height,
SCROLL_DURATION);
// trigger computeScroll
invalidate();
}
/**
* 更新footer離底部的距離
* @param delta
*/
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上拉足夠高才去加載
// more.
mFooterView.setState(XListViewFooter.STATE_READY);
} else {
mFooterView.setState(XListViewFooter.STATE_NORMAL);
}
}
mFooterView.setBottomMargin(height);
// setSelection(mTotalItemCount - 1); // scroll to bottom
}
/**
* 重置footer位置
*/
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) {//獲得觸摸時的y坐標
mLastY = ev.getRawY();
}
switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
mLastY = ev.getRawY();
break;
case MotionEvent.ACTION_MOVE:
final float deltaY = ev.getRawY() - mLastY;//下拉或者上拉了多少offset
mLastY = ev.getRawY();
if (getFirstVisiblePosition() == 0
&& (mHeaderView.getVisiableHeight() > 0 || deltaY > 0)) {//第一個item可見並且頭部部分顯示或者下拉操作,則表示處於下拉刷新狀態
// 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)) {//最後一個item可見並且footer被上拉顯示或者上拉操作,則表示處於上拉刷新狀態
// last item, already pulled up or want to pull up.
updateFooterHeight(-deltaY / OFFSET_RADIO);
}
break;
default://action_up
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.
* 下拉和上拉監聽器
*/
public interface IXListViewListener {
public void onRefresh();
public void onLoadMore();
}
}
public class XListViewHeader extends LinearLayout {
/**
* 下拉布局主體
*/
private LinearLayout mContainer;
/**
* 下拉箭頭
*/
private ImageView mArrowImageView;
/**
* 環形進度條
*/
private ProgressBar mProgressBar;
/**
* 提示文本
*/
private TextView mHintTextView;
private int mState = STATE_NORMAL;
private Animation mRotateUpAnim;
private Animation mRotateDownAnim;
/**
* 動畫時間
*/
private final int ROTATE_ANIM_DURATION = 180;
public final static int STATE_NORMAL = 0;//普通狀態
public final static int STATE_READY = 1;//下拉准備刷新
public final static int STATE_REFRESHING = 2;//正在加載
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) {
// 初始情況，設置下拉刷新view高度為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);
//旋轉動畫
mRotateUpAnim = new RotateAnimation(0.0f, -180.0f,
Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
0.5f);
//設置動畫時間
mRotateUpAnim.setDuration(ROTATE_ANIM_DURATION);
//動畫終止時停留在最後一幀,也就是保留動畫以後的狀態
mRotateUpAnim.setFillAfter(true);
//旋轉動畫
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) {// 顯示進度
mArrowImageView.clearAnimation();
mArrowImageView.setVisibility(View.INVISIBLE);
mProgressBar.setVisibility(View.VISIBLE);
} else {// 顯示箭頭圖片
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;
}
/**
* 設置下拉頭有效高度
* @param height
*/
public void setVisiableHeight(int height) {
if (height < 0)
height = 0;
LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) mContainer
.getLayoutParams();
lp.height = height;
mContainer.setLayoutParams(lp);
}
/**
* 獲得下拉頭有效高度
* @return
*/
public int getVisiableHeight() {
return mContainer.getLayoutParams().height;
}
}
public class XListViewFooter extends LinearLayout {
public final static int STATE_NORMAL = 0;//普通狀態
public final static int STATE_READY = 1;//上拉准備刷新
public final static int STATE_LOADING = 2;//正在加載
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);
}
/**
* 設置狀態
* @param state
*/
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);
}
}
/**
* 設置footer裡底部的高度
* @param height
*/
public void setBottomMargin(int height) {
if (height < 0) return ;
LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams)mContentView.getLayoutParams();
lp.bottomMargin = height;
mContentView.setLayoutParams(lp);
}
/**
* 獲得footer裡底部的高度
* @return
*/
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);
}
/**
* 初始化布局
* @param context
*/
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);
}
}
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