上一篇完成用户首页的UI实现，本篇接下来讲功能部分的实现，本页面主要的功能就用户关注的最新微博列表，从上一篇中知道本列表是用ID为Msglist的ListView控件来实现，本篇的主要就讲解如果获取微博列表数据给这个ListView提供显示数据。ListView每一条子数据分别由用户头像、用户昵称、发布时间、是否包含照片、微博内容这五部分组成，根据这五部分定义一个名为WeiBoInfo.java实体类，代码如下：
public class WeiBoInfo {
//文章id
private String id;
public String getId(){
return id;
}
public void setId(String id){
this.id=id;
}
//发布人id
private String userId;
public String getUserId(){
return userId;
}
public void setUserId(String userId){
this.userId=userId;
}
//发布人名字
private String userName;
public String getUserName(){
return userName;
}
public void setUserName(String userName){
this.userName=userName;
}
//发布人头像
private String userIcon;
public String getUserIcon(){
return userIcon;
}
public void setUserIcon(String userIcon){
this.userIcon=userIcon;
}
//发布时间
private String time;
public String getTime(){
return time;
}
public void setTime(String time)
{
this.time=time;
}
//是否有图片
private Boolean haveImage=false;
public Boolean getHaveImage(){
return haveImage;
}
public void setHaveImage(Boolean haveImage){
this.haveImage=haveImage;
}
//文章内容
private String text;
public String getText(){
return text;
}
public void setText(String text){
this.text=text;
}
}
然后在res/layout目录下新建名为weibo.xml的Layout用来控制ListView子项的显示部件，代码很简单不多解释了，直接看下面代码：
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal"> <ImageView android:id="@+id/wbicon" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/usericon" android:layout_margin="8px"> </ImageView> <LinearLayout android:layout_width="fill_parent" android:layout_height="wrap_content" android:orientation="vertical" android:paddingLeft="0px" android:paddingRight="5px" android:layout_marginTop="5px" android:layout_marginBottom="5px"> <RelativeLayout android:layout_width="fill_parent" android:layout_height="wrap_content"> <TextView android:id="@+id/wbuser" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textSize="15px" android:textColor="#424952" android:layout_alignParentLeft="true"> </TextView> <ImageView android:id="@+id/wbimage" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="3px" android:layout_marginRight="5px" android:layout_toLeftOf="@+id/wbtime"> </ImageView> <TextView android:id="@+id/wbtime" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentRight="true" android:textColor="#f7a200" android:textSize="12px"> </TextView> </RelativeLayout> <TextView android:id="@+id/wbtext" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textColor="#424952" android:textSize="13px" android:layout_marginTop="4px"> </TextView> </LinearLayout> </LinearLayout>
接下来为列表控件定义一个数据Adapter，代码如下：
private List<WeiBoInfo> wbList;
//微博列表Adapater
public class WeiBoAdapater extends BaseAdapter{
private AsyncImageLoader asyncImageLoader;
@Override
public int getCount() {
return wbList.size();
}
@Override
public Object getItem(int position) {
return wbList.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
asyncImageLoader = new AsyncImageLoader();
convertView = LayoutInflater.from(getApplicationContext()).inflate(R.layout.weibo, null);
WeiBoHolder wh = new WeiBoHolder();
wh.wbicon = (ImageView) convertView.findViewById(R.id.wbicon);
wh.wbtext = (TextView) convertView.findViewById(R.id.wbtext);
wh.wbtime = (TextView) convertView.findViewById(R.id.wbtime);
wh.wbuser = (TextView) convertView.findViewById(R.id.wbuser);
wh.wbimage=(ImageView) convertView.findViewById(R.id.wbimage);
WeiBoInfo wb = wbList.get(position);
if(wb!=null){
convertView.setTag(wb.getId());
wh.wbuser.setText(wb.getUserName());
wh.wbtime.setText(wb.getTime());
wh.wbtext.setText(wb.getText(), TextView.BufferType.SPANNABLE);
textHighlight(wh.wbtext,new char[]{'#'},new char[]{'#'});
textHighlight(wh.wbtext,new char[]{'@'},new char[]{':',' '});
textHighlight2(wh.wbtext,"http://"," ");
if(wb.getHaveImage()){
wh.wbimage.setImageResource(R.drawable.images);
}
Drawable cachedImage = asyncImageLoader.loadDrawable(wb.getUserIcon(),wh.wbicon, new ImageCallback(){
@Override
public void imageLoaded(Drawable imageDrawable,ImageView imageView, String imageUrl) {
imageView.setImageDrawable(imageDrawable);
}
});
if (cachedImage == null) {
wh.wbicon.setImageResource(R.drawable.usericon);
}else{
wh.wbicon.setImageDrawable(cachedImage);
}
}
return convertView;
}
上面的这个Adapter实现没有什么特别的很普通，不过这个中使用了AsyncImageLoader的方法，这个是用来实现用户头像图标的异步载入显示，这样能提高列表显示的速度，提高用户体验，AsyncImageLoader的代码如下：
public class AsyncImageLoader {
//SoftReference是软引用，是为了更好的为了系统回收变量
private HashMap<String, SoftReference<Drawable>> imageCache;
public AsyncImageLoader() {
imageCache = new HashMap<String, SoftReference<Drawable>>();
}
public Drawable loadDrawable(final String imageUrl,final ImageView imageView, final ImageCallback imageCallback){
if (imageCache.containsKey(imageUrl)) {
//从缓存中获取
SoftReference<Drawable> softReference = imageCache.get(imageUrl);
Drawable drawable = softReference.get();
if (drawable != null) {
return drawable;
}
}
final Handler handler = new Handler() {
public void handleMessage(Message message) {
imageCallback.imageLoaded((Drawable) message.obj, imageView,imageUrl);
}
};
//建立新一个新的线程下载图片
new Thread() {
@Override
public void run() {
Drawable drawable = loadImageFromUrl(imageUrl);
imageCache.put(imageUrl, new SoftReference<Drawable>(drawable));
Message message = handler.obtainMessage(0, drawable);
handler.sendMessage(message);
}
}.start();
return null;
}
public static Drawable loadImageFromUrl(String url){
URL m;
InputStream i = null;
try {
m = new URL(url);
i = (InputStream) m.getContent();
} catch (MalformedURLException e1) {
e1.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
Drawable d = Drawable.createFromStream(i, "src");
return d;
}
//回调接口
public interface ImageCallback {
public void imageLoaded(Drawable imageDrawable,ImageView imageView, String imageUrl);
}
}
完成上述的工作后，接下来就是显示微薄列表，
在HomeActivity的onCreate方法中调用loadList();代码如下：
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.home);
。。。。。。
loadList();
}
private void loadList(){
if(ConfigHelper.nowUser==null)
{
}
else
{
user=ConfigHelper.nowUser;
//显示当前用户名称
TextView showName=(TextView)findViewById(R.id.showName);
showName.setText(user.getUserName());
OAuth auth=new OAuth();
String url = "http://api.t.sina.com.cn/statuses/friends_timeline.json";
List params=new ArrayList();
params.add(new BasicNameValuePair("source", auth.consumerKey));
HttpResponse response =auth.SignRequest(user.getToken(), user.getTokenSecret(), url, params);
if (200 == response.getStatusLine().getStatusCode()){
try {
InputStream is = response.getEntity().getContent();
Reader reader = new BufferedReader(new InputStreamReader(is), 4000);
StringBuilder buffer = new StringBuilder((int) response.getEntity().getContentLength());
try {
char[] tmp = new char[1024];
int l;
while ((l = reader.read(tmp)) != -1) {
buffer.append(tmp, 0, l);
}
} finally {
reader.close();
}
String string = buffer.toString();
//Log.e("json", "rs:" + string);
response.getEntity().consumeContent();
JSONArray data=new JSONArray(string);
for(int i=0;i<data.length();i++)
{
JSONObject d=data.getJSONObject(i);
//Log.e("json", "rs:" + d.getString("created_at"));
if(d!=null){
JSONObject u=d.getJSONObject("user");
if(d.has("retweeted_status")){
JSONObject r=d.getJSONObject("retweeted_status");
}
//微博id
String id=d.getString("id");
String userId=u.getString("id");
String userName=u.getString("screen_name");
String userIcon=u.getString("profile_image_url");
Log.e("userIcon", userIcon);
String time=d.getString("created_at");
String text=d.getString("text");
Boolean haveImg=false;
if(d.has("thumbnail_pic")){
haveImg=true;
//String thumbnail_pic=d.getString("thumbnail_pic");
//Log.e("thumbnail_pic", thumbnail_pic);
}
Date date=new Date(time);
time=ConvertTime(date);
if(wbList==null){
wbList=new ArrayList<WeiBoInfo>();
}
WeiBoInfo w=new WeiBoInfo();
w.setId(id);
w.setUserId(userId);
w.setUserName(userName);
w.setTime(time);
w.setText(text);
w.setHaveImage(haveImg);
w.setUserIcon(userIcon);
wbList.add(w);
}
}
}catch (IllegalStateException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
}
}
if(wbList!=null)
{
WeiBoAdapater adapater = new WeiBoAdapater();
ListView Msglist=(ListView)findViewById(R.id.Msglist);
Msglist.setOnItemClickListener(new OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> arg0, View view,int arg2, long arg3) {
Object obj=view.getTag();
if(obj!=null){
String id=obj.toString();
Intent intent = new Intent(HomeActivity.this,ViewActivity.class);
Bundle b=new Bundle();
b.putString("key", id);
intent.putExtras(b);
startActivity(intent);
}
}
});
Msglist.setAdapter(adapater);
}
}
loadingLayout.setVisibility(View.GONE);
}
上面的loadList() 方法通过新浪Api接口http://api.t.sina.com.cn/statuses/friends_timeline.json获取当前登录用户及其所关注用户的最新微博消息，然后显示到列表中。
这样就完成了用户首页功能的开发。