你能帮我弄清楚如何实现Threads,所以当它等待服务器的答案时它不会冻结吗?
我已经尝试了5个小时左右,我简单地找不到在线程中使用它的方法,然后返回它以设置tv.setText();
package zee.rhs.dk;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
public class AndroidClientActivity extends Activity {
private String ip = "90.184.254.246";
private int port = 8081;
private String line;
private TextView tv;
private Button btn;
private Socket socket;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
tv = (TextView) findViewById(R.id.tv);
btn = (Button) findViewById(R.id.btn);
btn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
BufferedReader in = null;
PrintWriter out = null;
try {
socket = new Socket(ip, port);
out = new PrintWriter(socket.getOutputStream(), true);
out.println("update");
in = new BufferedReader(new InputStreamReader(socket
.getInputStream()));
while ((line = in.readLine()) == null) {
}
tv.setText(line);
} catch (UnknownHostException e) {
Toast.makeText(AndroidClientActivity.this,
"Can't reach ip: " + ip, Toast.LENGTH_LONG).show();
e.printStackTrace();
} catch (IOException e) {
Toast.makeText(AndroidClientActivity.this,
"Accept failed at port: " + port, Toast.LENGTH_LONG)
.show();
e.printStackTrace();
} finally {
out.close();
}
}
});
}
}
解决方法:
AsyncTask正是您要找的.从帮助页面:
private class DownloadFilesTask extends AsyncTask<URL, Integer, Long> {
protected Long doInBackground(URL... urls) {
int count = urls.length;
long totalSize = 0;
for (int i = 0; i < count; i++) {
totalSize += Downloader.downloadFile(urls[i]);
publishProgress((int) ((i / (float) count) * 100));
}
return totalSize;
}
protected void onProgressUpdate(Integer... progress) {
setProgressPercent(progress[0]);
}
protected void onPostExecute(Long result) {
showDialog("Downloaded " + result + " bytes");
}
}
请记住,doInBackground在单独的线程中运行,并且doInBackground完成后onPostExecute在UI线程中运行.