您好，在下面的代码点击登录按钮与互联网工作fine.suppose没有互联网连接，它没有工作我想显示diaglog没有互联网连接。
任何人都可以帮助我解决这个问题。
Login1.java
public class Login1 extends Activity {
protected static final int NOT_CONNECTED_TO_SERVICE = 0;
protected static final int FILL_BOTH_USERNAME_AND_PASSWORD = 1;
public static final String AUTHENTICATION_FAILED = "0";
public static final String FRIEND_LIST = "FRIEND_LIST";
protected static final int MAKE_SURE_USERNAME_AND_PASSWORD_CORRECT = 2 ;
protected static final int NOT_CONNECTED_TO_NETWORK = 3;
private EditText usernameText;
private EditText passwordText;
private Button cancelButton;
private IAppManager imService;
public static final int SIGN_UP_ID = Menu.FIRST;
public static final int EXIT_APP_ID = Menu.FIRST + 1;
private ServiceConnection mConnection = new ServiceConnection() {
public void onServiceConnected(ComponentName className, IBinder service) {
imService = ((IMService.IMBinder)service).getService();
if (imService.isUserAuthenticated() == true)
{
Intent i = new Intent(Login1.this, FriendList.class);
startActivity(i);
Login1.this.finish();
}
}
public void onServiceDisconnected(ComponentName className) {
imService = null;
Toast.makeText(Login1.this, R.string.local_service_stopped,
Toast.LENGTH_SHORT).show();
}
};
Boolean isInternetPresent = false;
ConnectionDetector cd;
private ProgressDialog progressDialog;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
startService(new Intent(Login1.this, IMService.class));
setContentView(R.layout.login_screen);
setTitle("Login");
Button loginButton = (Button) findViewById(R.id.login);
cancelButton = (Button) findViewById(R.id.cancel_login);
usernameText = (EditText) findViewById(R.id.userName);
passwordText = (EditText) findViewById(R.id.password);
loginButton.setOnClickListener(new OnClickListener(){
@SuppressWarnings("deprecation")
public void onClick(View arg0)
{
new LoadViewTask().execute();
isInternetPresent = cd.isConnectingToInternet();
if (!isInternetPresent) {
showAlertDialog(Login1.this, "No Internet Connection",
"You don't have internet connection.", true);
return;
}
if (imService == null) {
Toast.makeText(getApplicationContext(),R.string.not_connected_to_service, Toast.LENGTH_LONG).show();
return;
}
else if (imService.isNetworkConnected() == false)
{
Toast.makeText(getApplicationContext(),R.string.not_connected_to_network, Toast.LENGTH_LONG).show();
showDialog(NOT_CONNECTED_TO_NETWORK);
}
else if (usernameText.length() > 0 &&
passwordText.length() > 0)
{
Thread loginThread = new Thread(){
private Handler handler = new Handler();
@Override
public void run() {
String result = null;
try {
result = imService.authenticateUser(usernameText.getText().toString(), passwordText.getText().toString());
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
if (result == null || result.equals(AUTHENTICATION_FAILED))
{
handler.post(new Runnable(){
public void run() {
Toast.makeText(getApplicationContext(),R.string.make_sure_username_and_password_correct, Toast.LENGTH_LONG).show();
}
});
}
else {
handler.post(new Runnable(){
public void run() {
Intent i = new Intent(Login1.this, FriendList.class);
startActivity(i);
Login1.this.finish();
}
});
}
}
};
loginThread.start();
}
else {
Toast.makeText(getApplicationContext(),R.string.fill_both_username_and_password, Toast.LENGTH_LONG).show();
}
}
});
cancelButton.setOnClickListener(new OnClickListener(){
public void onClick(View arg0)
{
imService.exit();
finish();
}
});
}
@Override
protected Dialog onCreateDialog(int id)
{
int message = -1;
switch (id)
{
case NOT_CONNECTED_TO_SERVICE:
message = R.string.not_connected_to_service;
break;
case FILL_BOTH_USERNAME_AND_PASSWORD:
message = R.string.fill_both_username_and_password;
break;
case MAKE_SURE_USERNAME_AND_PASSWORD_CORRECT:
message = R.string.make_sure_username_and_password_correct;
break;
case NOT_CONNECTED_TO_NETWORK:
message = R.string.not_connected_to_network;
break;
default:
break;
}
if (message == -1)
{
return null;
}
else
{
return new AlertDialog.Builder(Login1.this)
.setMessage(message)
.setPositiveButton(R.string.OK, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
}
})
.create();
}
}
@Override
protected void onPause()
{
unbindService(mConnection);
super.onPause();
}
@Override
protected void onResume()
{
bindService(new Intent(Login1.this, IMService.class), mConnection , Context.BIND_AUTO_CREATE);
super.onResume();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
boolean result = super.onCreateOptionsMenu(menu);
menu.add(0, SIGN_UP_ID, 0, R.string.sign_up);
menu.add(0, EXIT_APP_ID, 0, R.string.exit_application);
return result;
}
@Override
public boolean onMenuItemSelected(int featureId, MenuItem item) {
switch(item.getItemId())
{
case SIGN_UP_ID:
Intent i = new Intent(Login1.this, SignUp.class);
startActivity(i);
return true;
case EXIT_APP_ID:
cancelButton.performClick();
return true;
}
return super.onMenuItemSelected(featureId, item);
}
@SuppressWarnings("deprecation")
public void showAlertDialog(Context context, String title, String message, Boolean status) {
AlertDialog alertDialog = new AlertDialog.Builder(context).create();
alertDialog.setTitle(title);
alertDialog.setMessage(message);
alertDialog.setIcon((status) ? R.drawable.success : R.drawable.fail);
alertDialog.setButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
}
});
alertDialog.show();
}
private class LoadViewTask extends AsyncTask<Void, Integer, Void>
{
//Before running code in separate thread
@Override
protected void onPreExecute()
{
progressDialog = ProgressDialog.show(Login1.this,"Loading...",
"Loading application View, please wait...", false, false);
progressDialog.show();
}
@Override
protected Void doInBackground(Void... params)
{
try
{
synchronized (this)
{
int counter = 0;
while(counter <= 4)
{
this.wait(850);
counter++;
publishProgress(counter*25);
}
}
}
catch (InterruptedException e)
{
e.printStackTrace();
}
return null;
}
@Override
protected void onProgressUpdate(Integer... values)
{
progressDialog.setProgress(values[0]);
}
@Override
protected void onPostExecute(Void result)
{
progressDialog.dismiss();
}
}
答案 0 :(得分：1)
添加此功能
public static boolean CheckInternet(Context context) {
ConnectivityManager connec = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
android.net.NetworkInfo wifi = connec.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
android.net.NetworkInfo mobile = connec.getNetworkInfo(ConnectivityManager.TYPE_MOBILE);
return wifi.isConnected() || mobile.isConnected();
}
此功能检查wifi或移动网络（如果可用），如果否，则返回true
并替换它：
if (!isInternetPresent) {
showAlertDialog(Login1.this, "No Internet Connection",
"You don't have internet connection.", true);
return;
}
通过此代码：
if (!CheckInternet(this)) {
new AlertDialog.Builder(this)
alertDialog.setTitle("Info");
alertDialog.setMessage("Internet not available, Cross check your internet connectivity and try again");
alertDialog.setIcon(android.R.drawable.ic_dialog_alert);
alertDialog.setButton("OK", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
finish();
}
});
alertDialog.show();
return;
}
答案 1 :(得分：0)
正如你所说：
我想显示diaglog，没有互联网连接。
使用此功能：
public static boolean isNetworkAvailable() {
ConnectivityManager cm = (ConnectivityManager) getApplicationContext().getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netInfo = cm.getActiveNetworkInfo();
return netInfo != null && netInfo.isConnectedOrConnecting();
}
并在您的代码中检查互联网连接：
if (!isNetworkAvailable()) {
// show your dialog here
}