安卓本身的ListView没有刷新功能，要想实现这一功能，就得继承ListView并重写它的方法。同时也要实现其OnScrollListener这一接口。
下拉刷新，需要在原本的ListView上部添加一个Head，ListView本身提供了addHeadView（）这一方法，但是没有实现刷新的功能，我们可以自定义Head的内容，并加上刷新的功能。
上拉加载更多数据与下拉刷新类似，是在ListView的下部添加一个Footer。具体实现代码如下：
import java.text.SimpleDateFormat;
import java.util.Date;
import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.RotateAnimation;
import android.widget.AbsListView;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ProgressBar;
import android.widget.TextView;
public class ReFlashListView extends ListView implements OnScrollListener {
View header;
View footer;
int headerHeight;
int firstVisibleItem; // 当前第一个可见Item的位置
boolean isRemark; // 标记第一个出现的Item
int startY; // 按下时的Y值
int state; // 当前的状态
int scrollState; // 滚动状态
final int NONE = 0; // 正常状态
final int PULL = 1; // 下拉刷新状态
final int RELESE = 2; // 松开释放状态
final int REFLASHING = 3; // 正在刷新状态
IReflashListener iReflashListener;
int totalItemCount;
int lastVisibleItem;
boolean isLoading; //正在加载
private TextView txtViewLoading = null;
private ProgressBar prgBarLoading = null;
public ReFlashListView(Context context) {
super(context);
initView(context);
// TODO Auto-generated constructor stub
}
public ReFlashListView(Context context, AttributeSet attrs) {
super(context, attrs);
initView(context);
// TODO Auto-generated constructor stub
}
public ReFlashListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
initView(context);
// TODO Auto-generated constructor stub
}
// 初始化界面，添加顶部布局至ListView
public void initView(Context context) {
LayoutInflater inflater = LayoutInflater.from(context);
header = inflater.inflate(R.layout.header_layout, null);
footer=inflater.inflate(R.layout.footer_layout, null);
footer.findViewById(R.id.load_layout).setVisibility(View.GONE);
measureView(header);
headerHeight = header.getMeasuredHeight();
topPadding(-headerHeight);
this.addHeaderView(header);
this.addFooterView(footer);
this.setOnScrollListener(this);
txtViewLoading = (TextView)footer.findViewById(R.id.text_loading);
prgBarLoading = (ProgressBar)footer.findViewById(R.id.loading_progress);
}
// 设置header布局的上边距
private void topPadding(int topPadding) {
header.setPadding(header.getPaddingLeft(), topPadding,
header.getPaddingRight(), header.getPaddingBottom());
header.invalidate();
}
// 通知父布局占用的宽，高
private void measureView(View view) {
ViewGroup.LayoutParams p = view.getLayoutParams();
if (p == null) {
p = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.WRAP_CONTENT);
}
int width = ViewGroup.getChildMeasureSpec(0, 0, p.width);
int height;
int tempHeight = p.height;
if (tempHeight > 0) {
height = MeasureSpec.makeMeasureSpec(tempHeight,
MeasureSpec.EXACTLY);
} else {
height = MeasureSpec.makeMeasureSpec(tempHeight,
MeasureSpec.UNSPECIFIED);
}
view.measure(width, height);
}
@Override
public void onScroll(AbsListView view, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
this.firstVisibleItem = firstVisibleItem;
this.totalItemCount=totalItemCount;
this.lastVisibleItem=firstVisibleItem+visibleItemCount;
}
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
this.scrollState = scrollState;
if(totalItemCount==lastVisibleItem && scrollState == SCROLL_STATE_IDLE){
if(!isLoading){
isLoading=true;
footer.findViewById(R.id.load_layout).setVisibility(View.VISIBLE);
iReflashListener.onLoad();
}
}
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
if (firstVisibleItem == 0) {
isRemark = true;
startY = (int) ev.getY();
}
break;
case MotionEvent.ACTION_MOVE:
onMove(ev);
break;
case MotionEvent.ACTION_UP:
if (state == RELESE) {
state = REFLASHING;
//刷新数据
iReflashListener.onReflash();
reflashViewByState();
} else if (state == PULL) {
state = NONE;
isRemark = false;
reflashViewByState();
}
break;
}
return super.onTouchEvent(ev);
}
/*
* 判断移动过程中的操作
*/
private void onMove(MotionEvent e) {
int tempY = (int) e.getY();
int space = tempY - startY;
int topPadding = space - headerHeight;
if (!isRemark) {
return;
}
switch (state) {
case NONE:
if (space > 0) {
state = PULL;
reflashViewByState();
}
break;
case PULL:
topPadding(topPadding);
if (space > headerHeight + 30
&& scrollState == SCROLL_STATE_TOUCH_SCROLL) {
state = RELESE;
reflashViewByState();
}
break;
case RELESE:
topPadding(topPadding);
if (space < headerHeight + 30) {
state = PULL;
reflashViewByState();
} else if (space <= 0) {
state = NONE;
isRemark = false;
reflashViewByState();
}
break;
}
}
/*
* 根据当前状态，改变界面显示
*/
private void reflashViewByState() {
TextView tip = (TextView) header.findViewById(R.id.tip);
ImageView arrow = (ImageView) header.findViewById(R.id.arrow);
ProgressBar progress = (ProgressBar) header.findViewById(R.id.progress);
RotateAnimation anim = new RotateAnimation(0, 180,
RotateAnimation.RELATIVE_TO_SELF, 0.5f,
RotateAnimation.RELATIVE_TO_SELF, 0.5f);
anim.setDuration(500);
anim.setFillAfter(true);
RotateAnimation anim1 = new RotateAnimation(180, 0,
RotateAnimation.RELATIVE_TO_SELF, 0.5f,
RotateAnimation.RELATIVE_TO_SELF, 0.5f);
anim1.setDuration(500);
anim1.setFillAfter(true);
switch (state) {
case NONE:
topPadding(-headerHeight);
arrow.clearAnimation();
break;
case PULL:
arrow.setVisibility(View.VISIBLE);
progress.setVisibility(View.GONE);
tip.setText("下拉可以刷新");
arrow.clearAnimation();
arrow.setAnimation(anim1);
break;
case RELESE:
arrow.setVisibility(View.VISIBLE);
progress.setVisibility(View.GONE);
tip.setText("松开可以刷新");
arrow.clearAnimation();
arrow.setAnimation(anim);
break;
case REFLASHING:
topPadding(50);
arrow.setVisibility(View.GONE);
progress.setVisibility(View.VISIBLE);
arrow.clearAnimation();
tip.setText("正在刷新...");
break;
}
}
public void reflashComplete(){
state=NONE;
reflashViewByState();
isRemark=false;
TextView lastupdatetime=(TextView)header.findViewById(R.id.last_update_time);
SimpleDateFormat format=new SimpleDateFormat("yyyy年MM月dd日 hh:mm:ss");
Date date=new Date(System.currentTimeMillis());
String time=format.format(date);
lastupdatetime.setText(time);
}
public void loadingComplete(){
isLoading=false;
footer.findViewById(R.id.load_layout).setVisibility(View.GONE);
}
public void allDataLoadingComplete(){
isLoading=false;
txtViewLoading.setText("全部数据已经加载完成");
prgBarLoading.setVisibility(View.GONE);
}
public void setInterfacs(IReflashListener iReflashListener){
this.iReflashListener=iReflashListener;
}
public interface IReflashListener{
public void onReflash();
public void onLoad();
}
}
重写ListView实现下拉刷新上拉加载
时间： 2024-09-30 06:45:08