我想在我的活动中显示一个进度条，其中包含使用套接字测试服务器连接的代码。我希望我的进度条仅在向服务器发送数据时可见。一旦我收到服务器的回复，应该取消进度并显示警告框，并显示消息“服务器忙”。但在我的屏幕上，从服务器收到回复后可以看到进度条。这是我的代码。
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mProgress = (ProgressBar) findViewById(R.id.progressBar1);
mProgress.setProgress(0);
checkdb();
}
private void checkdb() {
String message = "";
try {
serverIpAddress = InetAddress.getByName("192.168.1.133");
Log.d("TCP", "C: Connecting...");
socketObject = new Socket(serverIpAddress, 8221);
String str = "hi";
try {
Log.d("TCP", "C: Sending: '" + str + "'");
PrintWriter out = new PrintWriter(new BufferedWriter(
new OutputStreamWriter(socketObject.getOutputStream())), true);
out.println(str);
inputStream = socketObject.getInputStream();
inputDataStream = new DataInputStream(inputStream);
message = inputDataStream.readUTF();
Log.d("TCP", "C: Reply: '" + message + "'");
}
catch(IOException e)
{
Log.e("TCP", "S: Error", e);
}catch (Exception e) {
Log.e("TCP", "S: Error", e);
}
finally {
socketObject.close();
Log.e("TCP", "S: Error");
}
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
Log.e("TCP", "C: UnknownHostException", e);
e.printStackTrace();
}
catch(IOException e)
{
Log.e("TCP", "S: Error:", e);
//Code to show Alert box with message "IOException"
}
}
那么在我从服务器获得回复之前应该如何让我的进度条可见。如果我得到答复，则应取消进度条。 任何人请帮助我...
答案 0 :(得分：2)
以下是我在使用AsyncTask对用户进行身份验证时实现进度条的方法。看看这是否可以帮助你
private class LoginTask extends AsyncTask<String, Integer, Boolean>{
private final ProgressDialog dialog = new ProgressDialog(LoginActivity.this);
public LoginTask(LoginActivity activity) {
}
@Override
protected void onPreExecute() {
this.dialog.setMessage("Please wait..");
this.dialog.setIndeterminate(true) ;
this.dialog.setCancelable(false);
this.dialog.show();
}
@Override
protected Boolean doInBackground(String... params) {
try {
Thread.sleep(5000); //Execute long running task
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
@Override
protected void onPostExecute(Boolean result) {
if (this.dialog.isShowing()) { this.dialog.dismiss(); }
LoginActivity.this.processAuthenticationResult(result.booleanValue());
}
}
从我的LoginActivity中调用它，如下所示
new LoginTask(LoginActivity.this).execute(new String[]{userName, password});
答案 1 :(得分：0)
只需使用mProgress.setVisibility(View.GONE)或mProgress.setVisibility(View.VISIBLE)隐藏并显示您的小部件。
为避免您的主要用户活动被阻止，您需要在单独的线程中执行连接部分并使用Handler来更新它。代码就像：
在连接线程中通知UI活动......
mHandler.obtainMessage(Main_screen.MESSAGE_PGROGRESS_CHANGE_UPDATE, state, -1)
.sendToTarget();
在UI活动中：
private final Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
if (DEBUG)
Log.i(this.getClass().getSimpleName(),
"-> "
+ Thread.currentThread().getStackTrace()[2]
.getMethodName());
switch (msg.what) {
case MESSAGE_PGROGRESS_CHANGE_UPDATE:
if (DEBUG)
Log.i(this.getClass().getSimpleName(),
" MESSAGE_PGROGRESS_CHANGE_UPDATE: " + msg.arg1);
// do your update of progressbar or whatever here
break;
case MESSAGE_PGROGRESS_CHANGE_SYNCHRINIZATION:
if (DEBUG)
Log.i(this.getClass().getSimpleName(),
" MESSAGE_PGROGRESS_CHANGE_SYNCHRINIZATION: " + msg.arg1);
// do your update of progressbar or whatever here
break;
答案 2 :(得分：0)
<强> HI 您可以使用AsyncTask在后台进行服务器通信，并将结果显示在屏幕上。我希望这段代码可以帮助你。
public class PlasmaViewReDirectionTask extends
AsyncTask<Void, String, String> {
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
// showDialog("Fetching Video Url........");
favDialog = new Dialog(PlasmaView.this,
android.R.style.Theme_Translucent_NoTitleBar_Fullscreen);
favDialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
favDialog.getWindow().setFlags(
WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
favDialog.setContentView(R.layout.busypopup);
loadMessage = (TextView) favDialog
.findViewById(R.id.loadingmessgetext);
loadMessage.setText("Communicating with server........");
favDialog.setCancelable(false);
try {
favDialog.show();
} catch (Exception e) {
// TODO Auto-generated catch block
logger.info("Dialog " + e.getMessage());
}
}
@Override
protected String doInBackground(Void... params) {
String message = "";
try {
serverIpAddress = InetAddress.getByName("192.168.1.133");
Log.d("TCP", "C: Connecting...");
socketObject = new Socket(serverIpAddress, 8221);
String str = "hi";
try {
Log.d("TCP", "C: Sending: '" + str + "'");
PrintWriter out = new PrintWriter(new BufferedWriter(
new OutputStreamWriter(socketObject.getOutputStream())), true);
out.println(str);
inputStream = socketObject.getInputStream();
inputDataStream = new DataInputStream(inputStream);
message = inputDataStream.readUTF();
Log.d("TCP", "C: Reply: '" + message + "'");
}
catch(IOException e)
{
Log.e("TCP", "S: Error", e);
}catch (Exception e) {
Log.e("TCP", "S: Error", e);
}
finally {
socketObject.close();
Log.e("TCP", "S: Error");
}
} catch (UnknownHostException e) {
// TODO Auto-generated catch block
Log.e("TCP", "C: UnknownHostException", e);
e.printStackTrace();
}
catch(IOException e)
{
Log.e("TCP", "S: Error:", e);
//Code to show Alert box with message "IOException"
}
return message;
}
@Override
protected void onPostExecute(String result) {
try {
if (favDialog.isShowing()) {
favDialog.dismiss();
favDialog = null;
}
} catch (Exception e1) {
}
Toast.makeText(YourScreen.this, result, Toast.LENGTH_LONG).show();
super.onPostExecute(result);
}
}