Idea for sorting values from QLineEdits?

[stampede]

You are sorting the list, but you don't use it anymore later. Just display the numbers from this list to line edits, using a for loop like high_flyer suggested. You can use QString::number() method, no need for temporary QString objects here.
I'll give you some hints about the "for" loop:

QList<double> list;
    for( /*something*/ {
        double number = ...
        list << number;
    }                                                                            
    qSort(list.begin(), list.end(), qGreater<double>());
    // and display:
    for( /*something*/ ){
        in[/*?*/]->setText( QString::number(/*??*/) );
    }

QList<double> list;
    for( /*something*/ {
        double number = ...
        list << number;
    }                                                                            
    qSort(list.begin(), list.end(), qGreater<double>());
    // and display:
    for( /*something*/ ){
        in[/*?*/]->setText( QString::number(/*??*/) );
    }

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[ewwen]

Hi, thanks for your reply!

Well even if I fill, it doesn´t work.

QList<double> list;
        for(int i = 0; i < Num; ++i) {
        double number[i] = in[i]->text().toDouble(&ok);
        list << number[0] << number[1] << number[2] << number[3] << number[4];
        }
 
     qSort(list.begin(), list.end(), qGreater<double>());
        for(int i = 0; i < Num; ++i){
        in[i]->setText( QString::number());
       }

QList<double> list;
        for(int i = 0; i < Num; ++i) {
        double number[i] = in[i]->text().toDouble(&ok);
        list << number[0] << number[1] << number[2] << number[3] << number[4];
        }

     qSort(list.begin(), list.end(), qGreater<double>());
        for(int i = 0; i < Num; ++i){
        in[i]->setText( QString::number());
       }

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I don´t get the values, which I want to display in in[i] again after sorting.

This works better:

QList<double> list;
     bool ok;
     double number1 = in[0]->text().toDouble(&ok);
     double number2 = in[1]->text().toDouble(&ok);
     double number3 = in[2]->text().toDouble(&ok);
     double number4 = in[3]->text().toDouble(&ok);
     double number5 = in[4]->text().toDouble(&ok);
     list << number1 << number2 << number3 << number4 << number5;
 
     qSort(list.begin(), list.end(), qGreater<double>());

QList<double> list;
     bool ok;
     double number1 = in[0]->text().toDouble(&ok);
     double number2 = in[1]->text().toDouble(&ok);
     double number3 = in[2]->text().toDouble(&ok);
     double number4 = in[3]->text().toDouble(&ok);
     double number5 = in[4]->text().toDouble(&ok);
     list << number1 << number2 << number3 << number4 << number5;

     qSort(list.begin(), list.end(), qGreater<double>());

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but there I still have the problem to display the ordered values...

Can anyone give me an advice, where to search or what to consider? (I tried several attempts now, but no one worked)

[high_flyer]

You are confusing all kinds of stuff, and you clearly have no understanding of how basic variable deceleration works.
You should really first learn basic programming concepts, and C syntax before you start programming with C++ and Qt.

your original code could not even compile!

QList<double> list;
        for(int i = 0; i < Num; ++i) {
           list << in[i]->text().toDouble(&ok);
        }
 
     qSort(list.begin(), list.end(), qGreater<double>());
        for(int i = 0; i < Num; ++i){
        in[i]->setText( QString::number(list.at(i)));
       }

QList<double> list;
        for(int i = 0; i < Num; ++i) {
           list << in[i]->text().toDouble(&ok);
        }

     qSort(list.begin(), list.end(), qGreater<double>());
        for(int i = 0; i < Num; ++i){
        in[i]->setText( QString::number(list.at(i)));
       }

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[ewwen]

Hi high_flyer, thanks for your help! Now everything runs and I finally understood the problem...

I´m still learning to programme and not everything I try, I find in books or tutorials. You are a professional and I am a beginner.

[high_flyer]

ewwen, that is ok to learn, everyone was a beginner once.
But you are tackling Qt, which prerequisites C++ knowledge, where as you are still in your first steps with C/C++ syntax and principals, thus doing anything with Qt will only make it more difficult.
You should first concentrate on C/C++, and once you are comfortable with the language and basic concepts, you will find Qt very helpful.
Otherwise you will find Qt hard confusing and frustrating.