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  4. [SOLVED]Remember Last LineEdit data
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[SOLVED]Remember Last LineEdit data

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  • ? Offline
    ? Offline
    A Former User
    wrote on last edited by
    #1

    My App takes input for Id and Birthdate in QLineEdit and sends the form data as http post request.
    Is it possible for the last entered input to stay when app is closed and then restarted??

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    • A Offline
      A Offline
      andre
      wrote on last edited by
      #2

      Of course. Make it persistant via storing it to a file, or using the QSettings class. Either way, you will need to load the information back on the next run.

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      • ? Offline
        ? Offline
        A Former User
        wrote on last edited by
        #3

        Andre , Thanks for the Reply....but i really couldn't make out how can QSettings be used for this purpose...cazn u please help me with some example code? I ll be grateful to you :)

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        • A Offline
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          andre
          wrote on last edited by
          #4

          To effectively use QSettings, it's best to first make sure you use QApplication properly. After creating your QApplication instance, be sure to set the application name, organization, url, etc.

          To store a value, you create a QSettings instance, and use setValue(). You can group values into subgroups if you want, but for the purpose of this excersise, don't bother.

          Then, if you want to read back your value (on first show), you also create a QSettings instance, and use the value() method with an appropriate default value. If there is data found, the default value would be used.

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          • ? Offline
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            A Former User
            wrote on last edited by
            #5

            This the main.cpp file of my application ...Here idline is the pointer to QLineEdit taking input for Id
            @#include<QApplication>
            #include<websis.h>
            #include"gui.h"

            int main(int argc, char *argv[])
            {
            QApplication a(argc, argv);
            a.setApplicationName("Websis Desktop Application");
            a.setOrganizationName("LUG Manipal");
            a.setOrganizationDomain("rajatgupta431@gmail.com");
            qApp->addLibraryPath("C:/Qt/4.8.4/plugins/imageformats");

            QSettings *settings;
            settings = new QSettings;
            
            makegui gogoi;
            QVariant idvar;
            idvar.setValue(gogoi.idline->text());
            settings->setValue("Id",&idvar);
            gogoi.idline->setText(settings->value("id","not set").toString());
            
            return a.exec&#40;&#41;;
            

            }
            @
            Results are not as expected...Please look into it :)

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            • A Offline
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              andre
              wrote on last edited by
              #6

              You're not telling us what is "expected", so it is hard to judge where your code deviates from your plan

              Just use a QSettings object on the stack (line 14 & 15)

              What is makegui gogoi; doing? (line 17)

              Why do you set a pointer to a QVariant in your settings? (line 20)

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              • M Offline
                M Offline
                mlong
                wrote on last edited by
                #7

                Also, you're using "Id" in line 20, and "id" in line 21.

                Software Engineer
                My views and opinions do not necessarily reflect those of anyone -- living or dead, real or fictional -- in this universe or any other similar multiverse node. Void where prohibited. Your mileage may vary. Caveat emptor.

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                • ? Offline
                  ? Offline
                  A Former User
                  wrote on last edited by
                  #8

                  [quote author="Andre" date="1363711273"]# You're not telling us what is "expected", so it is hard to judge where your code deviates from your plan

                  Just use a QSettings object on the stack (line 14 & 15)

                  What is makegui gogoi; doing? (line 17)

                  Why do you set a pointer to a QVariant in your settings? (line 20)[/quote]

                  Expected is that , when user closes and restarts the application , the QLineEdit fiels already has the previously Entered Text...makegui gogoi ; declares the object of the class makegui that is responsible for making the gui part and then calling other neseccary funtions.....

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                  • ? Offline
                    ? Offline
                    A Former User
                    wrote on last edited by
                    #9

                    [quote author="mlong" date="1363711569"]Also, you're using "Id" in line 20, and "id" in line 21.
                    [/quote]

                    Fixed It :)

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                    • M Offline
                      M Offline
                      mlong
                      wrote on last edited by
                      #10

                      You can't just "bind" a QSettings value to a widget, which I think is what you're trying to do. QSettings doesn't work that way.

                      You'll need to store the text from your QLineEdit by calling QSettings::setValue() each time the text changes (either as the user type it, or when you process the values -- however it's done in your gui.) This won't typically be done in main(). It is most likely best handled in your makegui class. Also, at the time you build/initialize your gui is when you'll use QSettings::value() to set your text.

                      Software Engineer
                      My views and opinions do not necessarily reflect those of anyone -- living or dead, real or fictional -- in this universe or any other similar multiverse node. Void where prohibited. Your mileage may vary. Caveat emptor.

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                      • ? Offline
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                        A Former User
                        wrote on last edited by
                        #11

                        [quote author="Andre" date="1363698916"]Of course. Make it persistant via storing it to a file, or using the QSettings class. Either way, you will need to load the information back on the next run.[/quote]
                        Am unable to use QSettings for this...Can u guide me with the other Way of storing in A text file and then retrieving it from there?

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                        • A Offline
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                          andre
                          wrote on last edited by
                          #12

                          Using a text file is not going to be any easier.

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                          • ? Offline
                            ? Offline
                            A Former User
                            wrote on last edited by
                            #13

                            Can I get a line of code that saves text of QLineedit and on restarting the app , it is retrieved ?
                            Please help , its very important for my project ...

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                            • A Offline
                              A Offline
                              andre
                              wrote on last edited by
                              #14

                              No. The point is, that there isn't any such one line of code.

                              You've already been given many hints, but you refuse to take the hints given.

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                              • ? Offline
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                                A Former User
                                wrote on last edited by
                                #15

                                This is What was needed, its Done :)
                                @//read
                                QSettings settings("settingName");
                                QString aValue=settings.value("aKey").toString();

                                //write
                                QSettings settings("settingName");
                                QString somevalue=textedit.text();
                                settings.setValue("aKey",somevalue);
                                @

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