我想使用 AsyncTask 从 Java 服务器接收 ArrayList(在这种情况下)。可以肯定的是,我从服务器收到了一些东西,我正试图用 Toast 显示它。
代码如下:
public class MainActivity extends Activity {
private DataReceiving dRec;
private DataTransfer dTrans;
private EditText inputData;
private Button sendParametersBtn;
private Button startComputationBtn;
private TextView displayText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
inputData=(EditText) findViewById(R.id.InputText);
sendParametersBtn=(Button) findViewById(R.id.button1);
startComputationBtn=(Button) findViewById(R.id.button2);
displayText=(TextView) findViewById(R.id.textView1);
sendParametersBtn.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
dRec = new DataReceiving();
dRec.execute();
}
});
private class DataReceiving extends AsyncTask<Void, Void, ArrayList>
{
@Override
protected ArrayList doInBackground(Void... params) {
ArrayList b = new ArrayList();
try {
b = receive();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return b;
}
protected void onPostExecute(ArrayList result) {
super.onPostExecute(result);
Toast toast=Toast.makeText(getApplicationContext(), result.toString(), Toast.LENGTH_SHORT);
toast.show();
}
public ArrayList receive () throws IOException, ClassNotFoundException
{
ServerSocket s= new ServerSocket(8888);
Socket incoming =s.accept();
ObjectInputStream ios = new ObjectInputStream(incoming.getInputStream());
ArrayList b = (ArrayList) ios.readObject();
ios.close();
incoming.close();
s.close();
return b;
}
单击 sendParametersBtn 时没有任何反应。PS我可以成功地从Android传输到服务器。所以它不是连接或权限问题。
谢谢你的帮助