我已经用Acitvity改进了这个类，在此之前它是用ListActivity扩展的，这是因为我喜欢在这个类中使用setEmptyView。但是在我改变了这个类扩展了Activity后，它的列表项在点击时无法弹出对话框。有人可以给出一些建议吗？
ThirdActivity.java
public class ThirdActivity extends Activity{
Bundle b;
String user,line,result,datapassed,list;
DefaultHttpClient httpclient;
HttpPost httppost;
HttpResponse response;
InputStream is = null;
BufferedReader reader;
StringBuilder sb;
ArrayList<NameValuePair> nameValuePairs;
ListView lv;
IntentFilter intentFilter;
int notification = 1;
String str = "";
byte[] data;
int dlength;
String[] item = {"Track Location","Remove Friend"};
ArrayAdapter<String> adapter;
ArrayList<String> friend;
TextView emptyText;
public void onCreate(Bundle savedInstancesState)
{
super.onCreate(savedInstancesState);
setContentView(R.layout.list_screen);
user = getIntent().getExtras().getString("user");
Log.d("dg",user);
lv = (ListView) findViewById(R.id.list);
emptyText = (TextView)findViewById(R.id.empty);
getList();
}
}
public void getList(){
new Thread(){
public void run(){
try{
httpclient = new DefaultHttpClient();
httppost = new HttpPost("http://www.kryptoquest.com/tracker/friendlist.php");
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(1);
nameValuePairs.add(new BasicNameValuePair("Username", user));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
response = httpclient.execute(httppost);
is = response.getEntity().getContent();
}catch(Exception e){
Log.e("log_tag", "Error:"+e.toString());
}
//convert response to string
try{
reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
sb = new StringBuilder();
line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
Log.d("test",sb.toString());
is.close();
result = sb.toString();
result = result.substring(0, result.length()-1);
// Log.d("result",result);
friend = new ArrayList<String>(Arrays.asList(result.split("[*]")));
Log.d("size",String.valueOf(friend.size()));
runOnUiThread(new Runnable()
{
public void run(){
adapter = new ArrayAdapter<String>(ThirdActivity.this,android.R.layout.simple_list_item_1,friend);
lv.setAdapter(adapter);
lv.setEmptyView(emptyText);
}
});
}catch(Exception e){
Log.e("log_tag", "Error converting result "+e.toString());
}
}
}.start();
}
public void onItemClick( View v, final int position, long id){
AlertDialog.Builder adb = new AlertDialog.Builder(ThirdActivity.this);
adb.setItems(item, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
Toast.makeText(ThirdActivity.this, item[which], Toast.LENGTH_LONG).show();
if(item[which].equals("Track Location")){
AlertDialog.Builder adb = new AlertDialog.Builder(
ThirdActivity.this);
adb.setIcon(R.drawable.location);
adb.setTitle("Friend Location");
adb.setMessage("Do you want to track "
+ lv.getItemAtPosition(position) + "'s location?");
adb.setPositiveButton("Yes",
new DialogInterface.OnClickListener(){
public void onClick(DialogInterface dialog, int whichButton)
{
new Thread(){
public void run(){
try{
httpclient = new DefaultHttpClient();
httppost = new HttpPost("http://www.kryptoquest.com/tracker/track.php");
nameValuePairs = new ArrayList<NameValuePair>(2);
Log.d("12345678",user);
nameValuePairs.add(new BasicNameValuePair("Targetname", (String) lv.getItemAtPosition(position)));
Log.d("Targetname",(String) lv.getItemAtPosition(position));
nameValuePairs.add(new BasicNameValuePair("Username", user));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
response = httpclient.execute(httppost);
is = response.getEntity().getContent();
}catch(Exception e){
Log.e("log_tag", "Error:"+e.toString());
}
//convert response to string
try{
reader = new BufferedReader(new InputStreamReader(is,"iso-8859-1"),8);
sb = new StringBuilder();
line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
Log.d("test",sb.toString());
is.close();
result = sb.toString();
Intent i = new Intent(ThirdActivity.this,Map.class);
i.putExtra("location", result);
startActivity(i);
}catch(Exception e){
Log.e("log_tag", "Error converting result "+e.toString());
}
}
}.start();
}
});
adb.setNegativeButton("No", null);
adb.show();
}else{
AlertDialog.Builder adb=new AlertDialog.Builder(ThirdActivity.this);
adb.setTitle("Delete?");
adb.setMessage("Are you sure you want to delete " + (String) lv.getItemAtPosition(position));
Log.d("index", String.valueOf(position));
adb.setNegativeButton("Cancel", null);
adb.setPositiveButton("Ok", new AlertDialog.OnClickListener() {
String delete = (String) ((lv.getAdapter()).getItem(position));
public void onClick(DialogInterface dialog, final int which) {
// lv.invalidateViews();
new Thread(){
public void run(){
try{
httpclient = new DefaultHttpClient();
httppost = new HttpPost("http://www.kryptoquest.com/tracker/remove.php");
nameValuePairs = new ArrayList<NameValuePair>(2);
Log.d("12345678",user);
nameValuePairs.add(new BasicNameValuePair("Targetname", (String) lv.getItemAtPosition(position)));
nameValuePairs.add(new BasicNameValuePair("Username", user));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
response = httpclient.execute(httppost);
is = response.getEntity().getContent();
data = new byte[256];
StringBuffer buffer = new StringBuffer();
int len = 0; //100
while (-1 != (len = is.read(data)) )
{
buffer.append(new String(data, 0, len));
}
Log.d("MainActivity", buffer.toString());
if(buffer.charAt(0)=='Y')
{
runOnUiThread(new Runnable()
{
public void run()
{
Toast.makeText(ThirdActivity.this, (String)lv.getItemAtPosition(position)+" has removed from friendlist", Toast.LENGTH_LONG).show();
friend.remove(delete);
adapter.notifyDataSetChanged();
}
});
}
else
{
runOnUiThread(new Runnable()
{
public void run()
{
Toast.makeText(ThirdActivity.this, "Friend remove failed", Toast.LENGTH_LONG).show();
}
});
}
is.close();
}catch(Exception e){
Log.e("log_tag", "Error:"+e.toString());
}
}
}.start();
}});
adb.show();
}
}
});
AlertDialog ad = adb.create();
ad.show();
}
list_screen.xml
<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<ListView android:id="@+id/list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"/>
<TextView android:id="@+id/empty"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:text="@string/no_friend"
android:gravity="center_vertical|center_horizontal"
/>
</LinearLayout>
答案 0 :(得分：2)
因为您尚未将OnItemClickListener设置为ListView。因此，您的onItemClick()永远不会被调用。当您将OnItemClickListener扩展为Activity而不是Activity时，您必须明确地将ListActivity设置为ListView。