在Android中ListView下拉刷新、上拉載入更多示例一文中，Maxwin兄給出的控件比較強大，前面有詳細介紹，但是有個不足就是，里面使用了一些資源文件，包括圖片，String，layout，這樣不利于封裝打包，下面我將源碼進行改進，所有布局全部用代碼實現，這樣直接將src和assets打包成jar就成了一個非常方便以后使用的擴展ListView控件，代碼如下：

XListView：

/*** @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 com.home.view;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 yprivate Scroller mScroller; // used for scroll backprivate OnScrollListener mScrollListener; // user's scroll listener// the interface to trigger refresh and load more.private IXListViewListener mListViewListener;// -- header viewprivate 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 heightprivate boolean mEnablePullRefresh = true;private boolean mPullRefreshing = false; // is refreashing.// -- footer viewprivate 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 durationprivate 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 viewmHeaderView = new XListViewHeader(context);mHeaderViewContent = (RelativeLayout) mHeaderView.findViewById(XListViewHeader.RELAYOUT_ID);mHeaderTimeView = (TextView) mHeaderView.findViewById(XListViewHeader.HEAD_TIME_VIEW_ID);addHeaderView(mHeaderView);// init footer viewmFooterView = new XListViewFooter(context);// init header height mHeaderView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {@Overridepublic void onGlobalLayout() {mHeaderViewHeight = mHeaderViewContent.getHeight();getViewTreeObserver().removeGlobalOnLayoutListener(this);}});}@Overridepublic 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);} else {mPullLoading = false;mFooterView.show();mFooterView.setState(XListViewFooter.STATE_NORMAL);// both "pull up" and "click" will invoke load more.mFooterView.setOnClickListener(new OnClickListener() {@Overridepublic 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) { // 未處于刷新狀態，更新箭頭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();}}@Overridepublic 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();System.out.println("數據監測：" + getFirstVisiblePosition() + "---->"+ getLastVisiblePosition());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; // resetif (getFirstVisiblePosition() == 0) {// invoke refreshif (mEnablePullRefresh&& mHeaderView.getVisiableHeight() > mHeaderViewHeight) {mPullRefreshing = true;mHeaderView.setState(XListViewHeader.STATE_REFRESHING);if (mListViewListener != null) {mListViewListener.onRefresh();}}resetHeaderHeight();}if (getLastVisiblePosition() == mTotalItemCount - 1) {// invoke load more.if (mEnablePullLoad&& mFooterView.getBottomMargin() > PULL_LOAD_MORE_DELTA) {startLoadMore();}resetFooterHeight();}break;}return super.onTouchEvent(ev);}@Overridepublic void computeScroll() {if (mScroller.computeScrollOffset()) {if (mScrollBack == SCROLLBACK_HEADER) {mHeaderView.setVisiableHeight(mScroller.getCurrY());} else {mFooterView.setBottomMargin(mScroller.getCurrY());}postInvalidate();invokeOnScrolling();}super.computeScroll();}@Overridepublic void setOnScrollListener(OnScrollListener l) {mScrollListener = l;}@Overridepublic void onScrollStateChanged(AbsListView view, int scrollState) {if (mScrollListener != null) {mScrollListener.onScrollStateChanged(view, scrollState);}}@Overridepublic void onScroll(AbsListView view, int firstVisibleItem,int visibleItemCount, int totalItemCount) {// send to user's listenermTotalItemCount = 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();} }

XListViewFooter：

package com.home.view;import android.content.Context; import android.util.AttributeSet; import android.view.Gravity; import android.view.View; import android.widget.LinearLayout; import android.widget.ProgressBar; import android.widget.RelativeLayout; 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 RelativeLayout mContentView;private ProgressBar 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("松開載入更多");} else if (state == STATE_LOADING) {mProgressBar.setVisibility(View.VISIBLE);} else {mHintView.setVisibility(View.VISIBLE);mHintView.setText("查看更多");}}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;// 根布局LinearLayout moreView = new LinearLayout(mContext);moreView.setLayoutParams(new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));// 將根布局加到該LinearLayout中 addView(moreView);// 根布局里面的相對布局mContentView = new RelativeLayout(mContext);LinearLayout.LayoutParams linearLp1 = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);mContentView.setPadding(10, 10, 10, 10);// 將相對布局relayout加到moreView根布局中 moreView.addView(mContentView, linearLp1);// 進度條mProgressBarmProgressBar = new ProgressBar(mContext);RelativeLayout.LayoutParams relativeLp1 = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);relativeLp1.addRule(RelativeLayout.CENTER_IN_PARENT);mProgressBar.setVisibility(View.INVISIBLE);// 將mProgressBar加入相對布局relayout中 mContentView.addView(mProgressBar, relativeLp1);// 查看更多的TextViewmHintView = new TextView(mContext);mHintView.setText("查看更多");mHintView.setGravity(Gravity.CENTER);RelativeLayout.LayoutParams relativeLp2 = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);relativeLp2.addRule(RelativeLayout.CENTER_IN_PARENT);// 將其加入相對布局relayout中 mContentView.addView(mHintView, relativeLp2);}}

XListViewHeader：

package com.home.view;import java.io.IOException; import java.io.InputStream;import android.content.Context; import android.content.res.AssetManager; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.util.AttributeSet; import android.view.Gravity; import android.view.View; import android.view.ViewGroup; 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.RelativeLayout; 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 static final int LINEAROUT_1_ID = 1;public static final int RELAYOUT_ID = 2;public static final int HEAD_TIME_VIEW_ID = 3;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) {// 根布局mContainer = new LinearLayout(context);mContainer.setGravity(Gravity.BOTTOM);// 初始情況，設置下拉刷新view高度為0LinearLayout.LayoutParams linearLp1 = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, 0);// 將根布局加入該LinearLayout中 addView(mContainer, linearLp1);setGravity(Gravity.BOTTOM);// 里面的相對布局RelativeLayout relayout = new RelativeLayout(context);relayout.setId(RELAYOUT_ID);LinearLayout.LayoutParams linearLp2 = new LinearLayout.LayoutParams(LayoutParams.MATCH_PARENT, 60);// 將里面的相對布局加入根布局中 mContainer.addView(relayout, linearLp2);// 相對布局里的子線性布局1LinearLayout linear1 = new LinearLayout(context);linear1.setId(LINEAROUT_1_ID);RelativeLayout.LayoutParams relativeLp1 = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);relativeLp1.addRule(RelativeLayout.CENTER_IN_PARENT);linear1.setGravity(Gravity.CENTER);linear1.setOrientation(LinearLayout.VERTICAL);// 將子布局linear1加入relayout中 relayout.addView(linear1, relativeLp1);// 下拉刷新提示TextViewmHintTextView = new TextView(context);mHintTextView.setText("下拉刷新");LinearLayout.LayoutParams linearLp3 = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);// 將TextView加入linear1中 linear1.addView(mHintTextView, linearLp3);// 子線性布局1（linear1）里的線性布局linear12LinearLayout linear12 = new LinearLayout(context);LinearLayout.LayoutParams linearLp4 = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);linearLp4.setMargins(0, 3, 0, 0);// 將linear12加入linear1中 linear1.addView(linear12, linearLp4);// 提示時間TextViewTextView tv = new TextView(context);tv.setText("上次更新時間：");tv.setTextSize(12);// 將提示時間TextView加入linear12 linear12.addView(tv, linearLp3);// 時間值TextViewTextView tv2 = new TextView(context);tv2.setId(HEAD_TIME_VIEW_ID);tv2.setTextSize(12);// 將時間值TextView加入linear12 linear12.addView(tv2, linearLp3);// ImageViewmArrowImageView = new ImageView(context);RelativeLayout.LayoutParams relativeLp2 = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,ViewGroup.LayoutParams.WRAP_CONTENT);relativeLp2.rightMargin = 20;relativeLp2.addRule(RelativeLayout.CENTER_VERTICAL);relativeLp2.addRule(RelativeLayout.LEFT_OF, LINEAROUT_1_ID);mArrowImageView.setImageBitmap(readAssetImage(context));// 將ImageView加到相對布局relayout中 relayout.addView(mArrowImageView, relativeLp2);// ProgressBarmProgressBar = new ProgressBar(context);RelativeLayout.LayoutParams relativeLp3 = new RelativeLayout.LayoutParams(45, 45);relativeLp3.addRule(RelativeLayout.LEFT_OF, LINEAROUT_1_ID);relativeLp3.addRule(RelativeLayout.CENTER_VERTICAL);relativeLp3.rightMargin = 20;mProgressBar.setVisibility(View.INVISIBLE);// 將mProgressBar加到相對布局relayout中 relayout.addView(mProgressBar, relativeLp3);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) { // 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("下拉刷新");break;case STATE_READY:if (mState != STATE_READY) {mArrowImageView.clearAnimation();mArrowImageView.startAnimation(mRotateUpAnim);mHintTextView.setText("松開刷新數據");}break;case STATE_REFRESHING:mHintTextView.setText("正在加載...");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.getHeight();}/*** 讀取assets里面文件名為xlistview_arrow.png的圖片** @param context* @return bitmap*/private Bitmap readAssetImage(Context context) {AssetManager asset = context.getAssets();InputStream assetFile = null;Bitmap bitmap = null;try {assetFile = asset.open("xlistview_arrow.png");bitmap = BitmapFactory.decodeStream(assetFile);} catch (IOException e) {e.printStackTrace();}return bitmap;}}

然后將使用到的那張圖片放在assets目錄下和src一起打包即可。

轉載于:https://www.cnblogs.com/qiuyang1/p/3979808.html

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