I haven't read your code-snippet, but here is how i would do it:
When the user wants to login, do a showDialog(idDialogLogin),
containing the username/password fields Login/Cancel buttons.
When Login is pressed, dismiss the dialog and start a progress-dialog
and the actual logging in. Handle this through an AsyncTask:
onPreExecute shows the progress dialog. The background task does the
actual logging in (through http). onPostExecute either hides it
(successful login) or just does a showDialog(idDialogLogin) again of
the login-dialog on an unsuccessful login.
When cancel is pressed, just dismiss the dialog.
On Jan 25, 9:47 am, qmwestview <qmwestv...@googlemail.com> wrote:
> Hi there,
>
> I am having a problem about repeating Login dialog (an AlertDialog)
> and progress dialog, coordinating with http thread. I suppose
> repetitive Login dialog (if fail, continue) handling should be common
> and straightforward. I guess my approach must be wrong somewhere. I
> already spent 2 days on this and am desperate. So please help.
>
> The usecase is like this:
>
> I have a main activity.
>
> User starts the app, the main activity starts.
> Show a login dialog (generated by the main thread, i.e. from onCreate
> ()). The main thread then starts a wait_thread, which will wait for
> http to return data and check the data and decide what to do.
>
> After user input username/password and press login, a progress dialog
> starts.
>
> The progress dialog starts an http_thread to talk to the server and
> get replies. Once done, it will notify the waiting thread.
>
> If the user type in the right username password first time, the code
> works fine.
>
> But it always fail for 2nd time Login, i.e. When first login fail
> (wrong username/password), the wait_thread will generate 2nd Login
> dialog to let user repeat the login process. But after user hit the
> login on this 2nd Login dialog, the system always crashes.
>
> The exception here is:
>
> ERROR/AndroidRuntime(21880): Uncaught handler: thread main exiting due
> to uncaught exception
> ERROR/AndroidRuntime(21880): android.view.ViewRoot
> $CalledFromWrongThreadException: Only the original thread that created
> a view hierarchy can touch its views.
>
> The followings are part of the code.
> ...
> public class Test extends Activity implements Constants,Runnable{
> ...
>
> @Override
> public void onCreate(Bundle savedInstanceState) {
> ...
> showDialog(DIALOG_LOGIN); //
> startHttpWaitThread();
> }
>
> private void startHttpWaitThread(){
> try {
> Thread dialogThread = new Thread(this);
> dialogThread.start();
> } catch(Exception e){
> //showDialog(DIALOG_LOGIN);
> }
> }
> /* �...@override
> public void onStart() {
> super.onStart();
> } */
>
> public void run(){
> Looper.prepare();
>
> try {
> synchronized(httpReplyData){ // httpReplyData holds all needed
> data returned from server
> httpReplyData.wait();
> }
> } catch(Exception e) {
> e.printStackTrace();
> }
> if
> (httpReplyData.getHttpResult()!=HTTP_REPLY_STATUS_CODE_OK_200)
> showDialog(DIALOG_LOGIN);
> Looper.loop();
> }
>
> @Override
> protected Dialog onCreateDialog(int id) {
> switch (id) {
> case DIALOG_LOGIN:
> return getLoginDialog(this);//,
> case DIALOG_LOGIN_PROGRESS:
> return new LoginProgressDialog
> (ctxForLoginProgressDialog);// }
> return null;
> }
>
> private Dialog getLoginDialog(Context ctx) {//, String name,
> String pwd){
> ...
> dialogBuilder.setPositiveButton(R.string.login, new
> DialogInterface.OnClickListener() {
> public void onClick(DialogInterface dialog, int
> whichButton) {
> networkService.startHttpThread
> (HTTP_REQUEST_LOGIN_INDEX, getUsername(), getPassword()); //
> networkService is the HTTP manager
> showDialog(DIALOG_LOGIN_PROGRESS); //
> startHttpWaitThread();
> }
> });
> return dialogBuilder.create();
> }
>
> private class LoginProgressDialog extends ProgressDialog
> implements Constants{
> //private ProgressThread progressThread;
> public LoginProgressDialog(Context ctx){
> super(ctx);
> ...
> }
> }
>
> }
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~
> I also tried second approach, which moves the wait_thread into
> progress dialog class/object, following Google’s “Creating a
> ProgressDialog” (http://developer.android.com/guide/topics/ui/
> dialogs.html#ProgressDialog). The 2nd login dialog is started by the
> progress dialog. Its wait() method gets called ONLY once (that is
> before 3nd showDialog(DIALOG_LOGIN) gets called). Seems to me the
> unfinished progressDialog’s thread blocks new progressDialog to be
> generated, I mean, when new showDialog(DIALOG_LOGIN_PROGRESS) called,
> the system will continue to use last progressDialog which has already
> responded to the first notify call and won’t respond to the notify
> call any more. So although the http thread handles well and call
> notify in due time, no one is waiting for that notify. Thus the system
> just hungs, while progress dialog is doing it animation endlessly.
>
> The followings are part of the code:
> …
> public class Test {// extends Activity implements Constants {
> ...
> @Override
> public void onCreate(Bundle savedInstanceState) {
> ...
> showDialog(DIALOG_LOGIN); //
> }
>
> ...
> @Override
> protected Dialog onCreateDialog(int id) {
> switch (id) {
> case DIALOG_LOGIN:
> return getLoginDialog(this);//
> case DIALOG_LOGIN_PROGRESS:
> return new LoginProgressDialog(ctxForLoginProgressDialog);//
> }
> return null;
> }
> private Dialog getLoginDialog(Context ctx) {//, String name,
> String pwd){
> ...
> dialogBuilder.setPositiveButton(R.string.login, new
> DialogInterface.OnClickListener() {
> public void onClick(DialogInterface dialog, int
> whichButton) {
> ...
>
> networkService.startHttpThread(HTTP_REQUEST_LOGIN_INDEX,
> username, password);
> showDialog(DIALOG_LOGIN_PROGRESS); //
> }
> });
> return dialogBuilder.create();
> }
>
> private class LoginProgressDialog extends ProgressDialog
> implements Constants{
> private ProgressThread progressThread;
> public LoginProgressDialog(Context ctx){
> ...
> progressThread = new ProgressThread(handler);
> progressThread.start();
> }
> final Handler handler = new Handler() {
> public void handleMessage(Message msg) {
> int httpStatusCode =
> msg.getData().getInt("httpStatusCode");
>
> if (httpStatusCode == HTTP_REPLY_STATUS_CODE_OK_200){
> dismissDialog
> (DIALOG_LOGIN_PROGRESS);
> } else showDialog(DIALOG_LOGIN);
> }
> };
> private class ProgressThread extends Thread {
> Handler handler;
> ProgressThread(Handler handler){
> this.handler = handler;
> }
> public void run() {
> try {
> synchronized(httpReplyData){
> httpReplyData.wait();
> }
> } catch(Exception e) {
> e.printStackTrace();
> }
> Message msg = handler.obtainMessage();
> Bundle b = new Bundle();
> b.putInt("httpStatusCode", httpReplyData.getHttpResult
> ());
> msg.setData(b);
> handler.sendMessage(msg);
> }
> }
> }}
>
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> How should I correct the logic? Any help would be truly appreciated
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