我编写了一个代码来获取与 YouTube 中特定用户相关的所有视频，如下所示：
import java.util.ArrayList;
import java.util.Collection;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.conn.DefaultClientConnection;
import org.apache.http.protocol.HTTP;
import org.apache.http.util.EntityUtils;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONTokener;
import com.example.tstnetconnwithjson.tables.custome;
import com.example.tstnetconnwithjson.tables.videos;
import android.os.AsyncTask;
import android.os.Bundle;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.app.ProgressDialog;
import android.content.DialogInterface;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
public class MainActivity extends Activity {
Button search; ;
TextView name ;
ListView listview ;
ArrayList<videos > videolist;
ArrayAdapter< videos > adapter ;
AlertDialog.Builder alert ;
ProgressDialog progressdialog ;
EditText name;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
videolist = new ArrayList<videos>();
adapter = new ArrayAdapter<videos>(this, android.R.layout.simple_list_item_1 , android.R.id.text1,videolist);
name=(EditText) findViewById(R.id.editText1);
alert = new Builder(this);
alert.setTitle("Warnning" ) ;
alert.setMessage("You want to connect to the internet ..? " );
alert.setNegativeButton("No ", null);
alert.setPositiveButton("Ok", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface arg0, int arg1) {
String username=name.getText().toString();
new connection().execute("https://gdata.youtube.com/feeds/api/videos?author="+username+"&v=2&alt=jsonc");
}
});
progressdialog = new ProgressDialog(this);
progressdialog.setMessage("Wait Loading .... ");
progressdialog.setCancelable(false);
search = (Button) findViewById(R.id.button1);
name = (TextView) findViewById(R.id.textView1);
listview = (ListView) findViewById(R.id.listView1);
listview.setAdapter(adapter);
search.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
alert.show();
}
});
}
class connection extends AsyncTask<String, Integer, String>{
@Override
protected void onPreExecute() {
progressdialog.show();
super.onPreExecute();
}
@Override
protected String doInBackground(String... arg0) {
String s = GetUrlBody(arg0[0]);
return s;
}
@Override
protected void onPostExecute(String result) {
try{
JSONObject jo =(JSONObject) new JSONTokener(result).nextValue();
JSONObject feed = jo.optJSONObject("data");
JSONArray entry = feed.optJSONArray("items");
for(int i = 0 ; i<entry.length() ; i++){
String title = entry.getJSONObject(i).getString("title");
String thumbURL = entry.getJSONObject(i).getJSONObject("thumbnail").getString("sqDefault");
Log.d("after get image", "ok")
String url;
try {
url = entry.getJSONObject(i).getJSONObject("player").getString("mobile");
} catch (JSONException ignore) {
url = entry.getJSONObject(i).getJSONObject("player").getString("default");
}
String description = entry.getJSONObject(i).getString("description");
Log.d("after get description", "ok");
videos videoobject=new videos();
videoobject.setDecscrption(description);
videoobject.setImageurl(thumbURL);
videoobject.setVediourl(url);
videoobject.setVideoname(title);
videolist.add(videoobject);
}
listview.setAdapter(new custome(MainActivity.this,videolist));
Log.d("AFTER set custome ", "before notify changes");
adapter.notifyDataSetChanged();
}catch(Exception exception) {
Log.d("exception ", "nock nock nock....");
Log.e("json ", exception.getMessage());
}
progressdialog.dismiss();
super.onPostExecute(result);
}
String GetUrlBody (String Url ){
HttpClient client = new DefaultHttpClient();
HttpGet gethttp = new HttpGet(Url);
try{
HttpResponse response = client.execute(gethttp);
if(response.getStatusLine().getStatusCode() == 200){
String save =
EntityUtils.toString(response.getEntity(), HTTP.UTF_8);
return save;
}else {
return "Not Found";
}
}catch(Exception exception){}
return null;
}
}
}
客户类从基本适配器扩展，以便将图像视图设置为视频图像和文本视图设置为视频标题的列表视图。在 log cat 消息中，结果存在，但我的列表视图返回空。谁能告诉我为什么？这是服装列表视图的代码：
public class custome extends BaseAdapter {
ArrayList<videos> data=new ArrayList<videos>();
android.content.Context context1;
android.widget.TextView name;
ImageView picture;
public custome(Context context,ArrayList<videos>arrayList) {
// TODO Auto-generated constructor stub
context=context;
arrayList=data;
}
public int getCount() {
// TODO Auto-generated method stub
return data.size();
}
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return data.get(arg0);
}
public long getItemId(int arg0) {
// TODO Auto-generated method stub
return arg0;
}
public View getView(int arg0, View arg1, ViewGroup arg2) {
View view=arg1;
if(view==null)
{
LayoutInflater layoutInflater=(LayoutInflater) _c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view=layoutInflater.inflate(R.layout.listvideo,null);
}
name=(TextView) view.findViewById(R.id.textView1);
picture=(ImageView) view.findViewById(R.id.imageView1);
videos video = data.get(arg0);
name.setText(video.getVideoname());
URL url = null;
try {
url = new URL(video.getImageurl());
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Bitmap bitmap = null;
try {
bitmap = BitmapFactory.decodeStream(url.openConnection().getInputStream());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
picture.setImageBitmap(bitmap);
return view;
}
}