我的Android应用程序具有登录功能，它正在从我的在线服务器访问用户信息。它还可以通过电子邮件确认来检测注册用户是否已激活他/她的帐户。
但问题是，我的应用程序在从数据库中检索用户详细信息时几乎关闭了。我看过一些关于ProgressDialog的视频，我不知道它是否可以正确地插入到我的程序中，请帮帮我。 / p>
这是我的代码。
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.firstscreen);
initialise();
bGotoRegister.setOnClickListener(new View.OnClickListener()
{
public void onClick(View view)
{
Intent i = new Intent(getApplicationContext(), Register.class);
startActivity(i);
}
});
}
private void initialise()
{
// TODO Auto-generated method stub
etEmail = (EditText) findViewById(R.id.loginEmail);
etPassword = (EditText) findViewById(R.id.loginPassword);
bLogin = (Button) findViewById(R.id.loginSubmit);
tvEmailError = (TextView) findViewById (R.id.loginEmailError);
tvPasswordError = (TextView) findViewById (R.id.loginPasswordError);
bGotoRegister = (Button) findViewById (R.id.goToRegister);
bLogin.setOnClickListener(this);
}
public void onClick(View v)
{
httpclient = new DefaultHttpClient();
httppost = new HttpPost("http://mysite.com/login.php");
stringEmail = etEmail.getText().toString();
stringPassword = etPassword.getText().toString();
try
{
nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("stringEmail", stringEmail));
nameValuePairs.add(new BasicNameValuePair("stringPassword", stringPassword));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
response = httpclient.execute(httppost);
if(response.getStatusLine().getStatusCode()== 200)
{
entity = response.getEntity();
if(entity != null)
{
InputStream instream = entity.getContent();
JSONObject jsonResponse = new JSONObject(convertStreamToString(instream));
String errorEmail = jsonResponse.getString("errorEmail");
if (errorEmail != "")
{
tvEmailError.setText(errorEmail);
}else{}
String errorPassword = jsonResponse.getString("errorPassword");
if (errorPassword != "")
{
tvPasswordError.setText(errorPassword);
}else{}
String inactiveAccount = jsonResponse.getString("inactiveAccount");
if (inactiveAccount.length() != 0)
{
AlertDialog alert = new AlertDialog.Builder(FirstScreen.this).create();
alert.setCancelable(false);
alert.setMessage("Your account is currently inactive and unusable." + "\nDo you want to send an account activation message to your email now?");
alert.setButton("Yes", new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface arg0, int arg1)
{
httpclient = new DefaultHttpClient();
httppost = new HttpPost("http://mysite.com/activate2.php");
stringEmail = etEmail.getText().toString();
stringPassword = etPassword.getText().toString();
try
{
nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("stringEmail", stringEmail));
nameValuePairs.add(new BasicNameValuePair("stringPassword", stringPassword));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
response = httpclient.execute(httppost);
if(response.getStatusLine().getStatusCode()== 200)
{
entity = response.getEntity();
if(entity != null)
{
InputStream instream = entity.getContent();
JSONObject jsonResponse = new JSONObject(convertStreamToString(instream));
String successActivation = jsonResponse.getString("successActivation");
if (successActivation.length() != 0)
{
//Progress Dialog here.
Toast.makeText(getBaseContext(), "We successfully sent an activation message to your email account. Try to log in again after activating your account.", Toast.LENGTH_LONG).show();
}
else
{
Toast.makeText(getBaseContext(), "Sorry, we are unable to reach your email account.",Toast.LENGTH_SHORT).show();
}
}
}
}
catch (Exception e)
{
e.printStackTrace();
Toast.makeText(getBaseContext(), "Connection to the server is lost. Please check your internet connection.", Toast.LENGTH_SHORT).show();
}
}
});
alert.setButton2("Not now", new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface arg0, int arg1)
{
AlertDialog alert2 = new AlertDialog.Builder(FirstScreen.this).create();
alert2.setCancelable(false);
alert2.setMessage("Are you sure you want to exit?");
alert2.setButton("Yes", new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface arg0, int arg1)
{
finish();
}
});
alert2.setButton2("No", new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface arg0, int arg1)
{
//Do nothing
}
});
alert2.show();
}
});
alert.show();
}else{}
if ((errorEmail.length()==0) && (errorPassword.length()==0)&& (inactiveAccount.length()==0))
{
String dbEmail = jsonResponse.getString("dbEmail");
String dbPassword = jsonResponse.getString("dbPassword");
//---Store dbEmail and dbPassword to SharedPreferences---//
//-------------------------------------------------------//
Intent i = new Intent(getApplicationContext(), Construction.class);
startActivity(i);
finish();
}
}//if (entity!=null)..
}//if response()...
}//try..
catch(Exception e)
{
e.printStackTrace();
Toast.makeText(getBaseContext(), "Connection to the server is lost. Please check your internet connection.", Toast.LENGTH_SHORT).show();
}
}//END onClick()
答案 0 :(得分：0)
您正在主线程上建立HTTP连接，这是在Android中编程的一种糟糕方式。
Web Connection是一种阻塞调用，意味着您的主线程将被点击，直到服务器收到成功或失败的响应。
由于主要线程在网络连接中被阻止，您的应用程序无法响应其他事件，如Touch / tap或任何类型的生命周期事件，也无法更新UI。这就是您的应用程序崩溃/进程对话框中没有显示更新的原因。
我建议您使用AsyncTask进行任何与网络相关的任务，以免主线程被阻止。
答案 1 :(得分：0)
您正在进行网络操作在事件线程中登录和检索详细信息，而不是在事件线程之外的其他线程中或在AsyncTask中执行此操作。
按进度对话框，您可以显示正在进行某些处理。
我正在编写一个示例代码，介绍如何在程序中使用进度对话框，线程和处理程序：
public void onClick(View v)
{
progressDialog=ProgressDialog.show(v.getContext(), "Login", "Logging In...." );
Thread thread= new Thread()
{
public void run()
{
httpclient = new DefaultHttpClient();
httppost = new HttpPost("http://mysite.com/login.php");
stringEmail = etEmail.getText().toString();
stringPassword = etPassword.getText().toString();
try
{
nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("stringEmail", stringEmail));
nameValuePairs.add(new BasicNameValuePair("stringPassword", stringPassword));
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
response = httpclient.execute(httppost);
if(response.getStatusLine().getStatusCode()== 200)
{
entity = response.getEntity();
if(entity != null)
{
InputStream instream = entity.getContent();
JSONObject jsonResponse = new JSONObject(convertStreamToString(instream));
String errorEmail = jsonResponse.getString("errorEmail");
if (errorEmail != "")
{
tvEmailError.setText(errorEmail);
}else{}
String errorPassword = jsonResponse.getString("errorPassword");
if (errorPassword != "")
{
Message msg= errHandler.obtainMessage();
msg.obj=errorPassword;
errHandler.sendMessage(msg);
}else{}
//
}//if (entity!=null)..
}//if response()...
}//try..
catch(Exception e)
{
e.printStackTrace();
Toast.makeText(getBaseContext(), "Connection to the server is lost. Please check your internet connection.", Toast.LENGTH_SHORT).show();
}
}
}
Handler errHandler=new Handler()
{
public void handleMessage(Message msg)
{
progressDialog.dismiss();
String strErr=(String)msg.obj;
tvEmailError.setText(strErr);
}
};