Android腾讯微博客户端开发5:利用FootView实现ListView滑动动态加载实现分页
老规矩，先上图
这张图片左边部分和右边部分还是有很大的不同，不是指内容上，是指布局上，左边的是我今天写这次代码之前的布局，root是用的RelativeLayout，右边是用的FrameLayout，体现在界面上就是右边的list内容可以顶到最上面，而左边的list是在上面的topBar下面。
看布局代码：布局代码还用到了include，主要是用来重用布局的。
把图片往下拉，此时还未到加载到数据的最底部。
继续往下拉，ok，见底了，看到更多的提示了嘛，点击他
出现进度条提示
加载完毕之后显示新的一页，继续往下拉，又会看见更多提示，然后如此循环。主要是利用了隐藏。
下面看看主的Activity的代码：
下面的布局文件是你所看见的更多提示和下方的进度条布局文件：
这张图片左边部分和右边部分还是有很大的不同，不是指内容上，是指布局上，左边的是我今天写这次代码之前的布局，root是用的RelativeLayout，右边是用的FrameLayout，体现在界面上就是右边的list内容可以顶到最上面，而左边的list是在上面的topBar下面。
看布局代码：布局代码还用到了include，主要是用来重用布局的。
<?xml version="1.0" encoding="utf-8"?> <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent"> <LinearLayout android:orientation="vertical" android:background="#ffffffff" android:layout_width="fill_parent" android:layout_height="fill_parent"> <ListView android:id="@id/android:list" android:paddingTop="45.0dip" android:paddingBottom="50.0dip" android:layout_width="fill_parent" android:cacheColorHint="#00000000" android:fadingEdge="none" android:fastScrollEnabled="false" android:clipToPadding="false" android:layout_height="wrap_content" android:divider="@drawable/list_divider"/> <TextView android:text="" android:textSize="20.0sp" android:textColor="#ff5a5a5a" android:gravity="center_horizontal" android:layout_width="fill_parent" android:layout_height="wrap_content" android:paddingTop="15.0dip" android:visibility="invisible"/> </LinearLayout> <include android:id="@+id/home_top" layout="@layout/top_panel" android:layout_width="fill_parent" android:layout_height="wrap_content" /> </FrameLayout>
把图片往下拉，此时还未到加载到数据的最底部。
继续往下拉，ok，见底了，看到更多的提示了嘛，点击他
出现进度条提示
加载完毕之后显示新的一页，继续往下拉，又会看见更多提示，然后如此循环。主要是利用了隐藏。
下面看看主的Activity的代码：
public class HomeTimeLineActivity extends ListActivity implements OnItemClickListener,OnItemLongClickListener{
private DataHelper dataHelper;
private UserInfo user;
private MyWeiboSync weibo;
private ListView listView;
private HomeAdapter adapter;
private JSONArray array;
private AsyncImageLoader asyncImageLoader;
private Handler handler;
private ProgressDialog progressDialog;
private View top_panel;
private Button top_btn_left;
private Button top_btn_right;
private TextView top_title;
private LinearLayout list_footer;
private TextView tv_msg;
private LinearLayout loading;
private List<JSONObject> list;//微博数据列表
private ExecutorService executorService;
private static int PAGE_SIZE = 5;//每页显示的微博条数
private int TOTAL_PAGE = 0;//当前已经记在的微博页数
private static int THREADPOOL_SIZE = 5;//线程池的大小
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.home);
setUpViews();
setUpListeners();
dataHelper = DataBaseContext.getInstance(getApplicationContext());
weibo = WeiboContext.getInstance();
List<UserInfo> userList = dataHelper.GetUserList(false);
SharedPreferences preferences = getSharedPreferences("default_user",Activity.MODE_PRIVATE);
String nick = preferences.getString("user_default_nick", "");//取得默认账号信息
if (nick != "") {
user = dataHelper.getUserByName(nick,userList);
top_title.setText(nick);//顶部工具栏昵称
}
weibo.setAccessTokenKey(user.getToken());
weibo.setAccessTokenSecrect(user.getTokenSecret());
progressDialog = new ProgressDialog(HomeTimeLineActivity.this);// 生成一个进度条
progressDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
progressDialog.setTitle("请稍等");
progressDialog.setMessage("正在读取数据中!");
handler = new GetHomeTimeLineHandler();
executorService.submit(new GetHomeTimeLineThread());//耗时操作,开启一个新线程获取数据
progressDialog.show();
}
private void setUpViews(){
list_footer = (LinearLayout)LayoutInflater.from(HomeTimeLineActivity.this).inflate(R.layout.list_footer, null);
tv_msg = (TextView)list_footer.findViewById(R.id.tv_msg);
loading = (LinearLayout)list_footer.findViewById(R.id.loading);
listView = getListView();
top_panel = (View)findViewById(R.id.home_top);
top_btn_left = (Button)top_panel.findViewById(R.id.top_btn_left);
top_btn_right = (Button)top_panel.findViewById(R.id.top_btn_right);
top_title = (TextView)top_panel.findViewById(R.id.top_title);
listView.addFooterView(list_footer);//这儿是关键中的关键呀，利用FooterVIew分页动态加载
list = new ArrayList<JSONObject>();
executorService = Executors.newFixedThreadPool(THREADPOOL_SIZE);
}
private void setUpListeners(){
listView.setOnItemClickListener(this);
listView.setOnItemLongClickListener(this);
top_btn_right.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(HomeTimeLineActivity.this,AddWeiboActivity.class);
startActivity(intent);
}
});
tv_msg.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
//Toast.makeText(HomeTimeLineActivity.this, "我将消失了", Toast.LENGTH_SHORT).show();
executorService.submit(new GetHomeTimeLineThread());
tv_msg.setVisibility(View.GONE);//隐藏更多提示的TextView
loading.setVisibility(View.VISIBLE);//显示最下方的进度条
}
});
}
class GetHomeTimeLineHandler extends Handler {
@Override
public void handleMessage(Message msg) {
adapter = new HomeAdapter(HomeTimeLineActivity.this, list);
listView.setAdapter(adapter);
listView.setSelection((TOTAL_PAGE-1)*PAGE_SIZE+1);//设置最新获取一页数据成功后显示数据的起始数据
progressDialog.dismiss();// 关闭进度条
loading.setVisibility(View.GONE);//隐藏下方的进度条
tv_msg.setVisibility(View.VISIBLE);//显示出更多提示TextView
}
}
class GetHomeTimeLineThread extends Thread {
@Override
public void run() {
refreshList();
Message msg = handler.obtainMessage();//通知线程来处理范围的数据
handler.sendMessage(msg);
}
}
private void refreshList(){
String jsonStr = weibo.getHomeMsg(weibo.getAccessTokenKey(), weibo.getAccessTokenSecrect(), PageFlag.PageFlag_First, (TOTAL_PAGE+1)*PAGE_SIZE);
try {
JSONObject dataObj = new JSONObject(jsonStr).getJSONObject("data");
array = dataObj.getJSONArray("info");
if(array!=null&&array.length()>0){
TOTAL_PAGE++;
list.clear();
int lenth =array.length();
for(int i = 0;i<lenth;i++){
list.add(array.optJSONObject(i));
}
}
} catch (JSONException e) {
e.printStackTrace();
}
}
class HomeAdapter extends BaseAdapter {
private Context context;
private LayoutInflater inflater;
private List<JSONObject> list;
public HomeAdapter(Context context, List<JSONObject> list) {
super();
this.context = context;
this.list = list;
this.inflater = LayoutInflater.from(context);
}
@Override
public int getCount() {
return list.size();
}
@Override
public Object getItem(int position) {
return list.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
asyncImageLoader = new AsyncImageLoader();
HomeViewHolder viewHolder = new HomeViewHolder();
JSONObject data = (JSONObject)list.get(position);
JSONObject source = null;
convertView = inflater.inflate(R.layout.home_list_item, null);
try {
source = data.getJSONObject("source");
} catch (JSONException e1) {
e1.printStackTrace();
}
viewHolder.home_headicon = (ImageView) convertView.findViewById(R.id.home_headicon);
viewHolder.home_nick = (TextView) convertView.findViewById(R.id.home_nick);
viewHolder.home_hasimage = (ImageView) convertView.findViewById(R.id.home_hasimage);
viewHolder.home_timestamp = (TextView) convertView.findViewById(R.id.home_timestamp);
viewHolder.home_origtext = (TextView) convertView.findViewById(R.id.home_origtext);
viewHolder.home_source = (TextView) convertView.findViewById(R.id.home_source);
if(data!=null){
try {
convertView.setTag(data.get("id"));
//viewHolder.home_headicon.setImageDrawable(ImageUtil.getDrawableFromUrl(data.getString("head")+"/100"));//同步加载图片
viewHolder.home_nick.setText(data.getString("nick"));
viewHolder.home_timestamp.setText(TimeUtil.converTime(Long.parseLong(data.getString("timestamp"))));
//viewHolder.home_origtext.setText(data.getString("origtext"), TextView.BufferType.SPANNABLE);
/*Spannable spannable = (Spannable)viewHolder.home_origtext.getText();//加高亮显示
spannable.setSpan(new BackgroundColorSpan(Color.RED), 0, 1, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);*/
SpannableString spannable = new SpannableString(data.getString("origtext"));
//把字符串解析成本地表情
spannable = TextUtil.getImageSpannableString(spannable, RegexUtil.getStartAndEndIndex(data.getString("origtext"), Pattern.compile("\\/[\u4e00-\u9fa5a-zA-Z]{1,3}")), getResources());
viewHolder.home_origtext.setText(spannable);
if(source!=null){
viewHolder.home_source.setText(source.getString("nick")+":"+source.getString("origtext"));
viewHolder.home_source.setBackgroundResource(R.drawable.home_source_bg);
}
//异步加载图片
Drawable cachedImage = asyncImageLoader.loadDrawable(data.getString("head")+"/100",viewHolder.home_headicon, new ImageCallback(){
@Override
public void imageLoaded(Drawable imageDrawable,ImageView imageView, String imageUrl) {
imageView.setImageDrawable(imageDrawable);
}
});
if (cachedImage == null) {
viewHolder.home_headicon.setImageResource(R.drawable.icon);
} else {
viewHolder.home_headicon.setImageDrawable(cachedImage);
}
if(data.getJSONArray("image")!=null){
viewHolder.home_hasimage.setImageResource(R.drawable.hasimage);
}
} catch (JSONException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
return convertView;
}
}
static class HomeViewHolder {
private ImageView home_headicon;
private TextView home_nick;
private TextView home_timestamp;
private TextView home_origtext;
private TextView home_source;
private ImageView home_hasimage;
}
@Override
public boolean onItemLongClick(AdapterView<?> arg0, View arg1, int position,long arg3) {
CharSequence [] items = null;
try {
items= new CharSequence[]{"转播","对话","点评","收藏",((JSONObject)array.opt(position)).getString("nick"),"取消"};
} catch (JSONException e) {
e.printStackTrace();
}
new AlertDialog.Builder(HomeTimeLineActivity.this).setTitle("选项").setItems(items,new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
switch (which) {
case 0: {
}
break;
case 1: {
}
break;
case 2: {
}
break;
case 3: {
}
break;
case 4: {
}
break;
case 5: {
}
break;
default:
break;
}
}
}).show();
return false;
}
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int position, long arg3) {
JSONObject weiboInfo = (JSONObject)array.opt(position);
Intent intent = new Intent(HomeTimeLineActivity.this, WeiboDetailActivity.class);
try {
intent.putExtra("weiboid", weiboInfo.getString("id"));
startActivity(intent);
} catch (JSONException e) {
e.printStackTrace();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu){
super.onCreateOptionsMenu(menu);
MenuInflater menuInflater = getMenuInflater();
menuInflater.inflate(R.menu.home_timeline_menu, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.menu_settings: {
}
break;
case R.id.menu_official: {
}
break;
case R.id.menu_feedback: {
}
break;
case R.id.menu_account: {
Intent intent = new Intent(HomeTimeLineActivity.this,
AccountActivity.class);
startActivity(intent);
}
break;
case R.id.menu_about: {
Intent intent = new Intent(HomeTimeLineActivity.this,
AddWeiboActivity.class);
startActivity(intent);
}
break;
case R.id.menu_quit: {
}
break;
default:
break;
}
return true;
}
}
下面的布局文件是你所看见的更多提示和下方的进度条布局文件：
<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout android:layout_width="fill_parent" android:layout_height="wrap_content" android:minHeight="?android:listPreferredItemHeight"
xmlns:android="http://schemas.android.com/apk/res/android">
<TextView android:textSize="16.0sp" android:textColor="#ff545454" android:gravity="center" android:id="@id/tv_msg" android:layout_width="fill_parent" android:layout_height="fill_parent" android:text="更多"/>
<LinearLayout android:gravity="center" android:layout_gravity="center" android:orientation="horizontal" android:id="@id/loading" android:layout_width="fill_parent" android:layout_height="fill_parent">
<ProgressBar android:layout_gravity="center_vertical" android:id="@id/footprogress" android:layout_width="wrap_content" android:layout_height="wrap_content" android:indeterminateBehavior="repeat" style="?android:progressBarStyleSmallInverse" />
<TextView android:textColor="#ff000000" android:gravity="left|center" android:padding="3.0px" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="读取中" />
</LinearLayout>
</LinearLayout>