Compile problem

Q139 · wrote on 1 Sept 2019, 16:43

Hello guys,

Im getting this error when attempting to compile: U:\proj\dfw\mainwindow.cpp:-1: error: undefined reference to `void ui_sync_and_save::addUiItem<int>(QObject*, int&, uiItemMath, double)'

mainWin .h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
#include "../usual/ui_sync_and_save.h"

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:


    explicit MainWindow(QWidget *parent = nullptr);
    ~MainWindow();
   ui_sync_and_save test;
   int val=0;
private slots:

private:
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H


}

MainWindow::~MainWindow()
{
    delete ui;
}

mainWin .cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    test.addUiItem(ui->checkBox,val);//compile problem occurs here<<<<<

}

MainWindow::~MainWindow()
{
    delete ui;
}

include .h

#ifndef UI_SYNC_AND_SAVE_H
#define UI_SYNC_AND_SAVE_H

#include <QObject>
#include "QSettings"

using namespace std;

enum uiOp{
    valToUi,
    valFromUi,
    fileFromUi,
    fileToUiAndPtr
};

enum uiItemMath{
   noCorrection,add,rem,multip,divide
};

class ui_sync_and_save : public QObject
{
   // Q_OBJECT
public:

    ui_sync_and_save();



    enum uiItems{
        spinBox,doubleSpinBox,checkBox,radioButton,dateTimeEdit
    };

    struct uiItem{
        QObject*ptr;
        void*valPtr;
        bool writeLock=0;
        uiItems type;
        uiItemMath mathOp;
        double mathVal;
    };
    vector<uiItem>uiItems;

    template <typename S>
    void addUiItem(QObject*uiItem,S&setVariable,uiItemMath correctionOp=noCorrection,double correctionVal=0);
    void syncUiVals(QObject *target=NULL, uiOp op=uiOp::valFromUi);

    QSettings uiSet;
    void saveUiValsToFile(QString path);
    void loadUiValsFromFile(QString path);

    bool setWriteLock(QObject*uiItem, bool lock);

    template <typename Val>
    QString n(Val num,char decimals=2){
       if(typeid(num)==typeid(double)){
           return QString::number(num,'f',decimals);
       }else{
           return QString::number(num);
       }
    }

private:
    template <typename V>
    V valCorrection(V val,uiItem&itm,uiOp op=valFromUi);

public slots:
    void syncSingleVal();

signals:
    QString errorMsg(QString error){
        return error;
    }
};

#endif // UI_SYNC_AND_SAVE_H

include .cpp

#include "ui_sync_and_save.h"
#include "QDoubleSpinBox"
#include "QSpinBox"
#include "QCheckBox"
#include "QRadioButton"
#include "QDateTimeEdit"

ui_sync_and_save::ui_sync_and_save()
{

}

template<typename S>//possibly template related mistake here<<<<<<<<
void ui_sync_and_save::addUiItem(QObject *uiItem, S &setVar, uiItemMath mathOp, double mathVal)
{
    ui_sync_and_save::uiItem item;
     item.ptr=uiItem;
     item.valPtr=&setVar;
     item.mathOp=mathOp;
     item.mathVal=mathVal;

         QDoubleSpinBox*dsBox=qobject_cast<QDoubleSpinBox*>(item.ptr);
         if (dsBox != NULL){
             item.type=doubleSpinBox;
             connect(dsBox, SIGNAL(valueChanged(double)), this, SLOT(syncSingleVal()));
             uiItems.emplace_back(item);
             return;
         }

         QSpinBox*sBox=qobject_cast<QSpinBox*>(item.ptr);
         if (sBox != NULL){
             item.type=spinBox;
             connect(sBox, SIGNAL(valueChanged(int)), this, SLOT(syncSingleVal()));
             uiItems.emplace_back(item);
             return;
         }

         QCheckBox*cBox=qobject_cast<QCheckBox*>(item.ptr);
         if (cBox != NULL){
             item.type=checkBox;
             connect(cBox, SIGNAL(stateChanged(int)), this, SLOT(syncSingleVal()));
             uiItems.emplace_back(item);
             return;
         }
         QRadioButton*rBut=qobject_cast<QRadioButton*>(item.ptr);
         if (rBut != NULL){
             item.type=radioButton;
             connect(rBut, SIGNAL(pressed()), this, SLOT(syncSingleVal()));
             uiItems.emplace_back(item);
             return;
         }


         QDateTimeEdit*dtEdit=qobject_cast<QDateTimeEdit*>(item.ptr);
         if (dtEdit != NULL){
             item.type=dateTimeEdit;
             connect(dtEdit, SIGNAL(dateTimeChanged(QDateTime)), this, SLOT(uuendaSet()));
             uiItems.emplace_back(item);
             return;
         }

       emit errorMsg("UiItemCastsFailed");

}


#ifdef QT_DEBUG
    int nullCounter=0;
#endif
    void ui_sync_and_save::syncUiVals(QObject *target,uiOp op)
    {

    #ifdef QT_DEBUG
        if(op==uiOp::valFromUi && target==NULL){
            nullCounter++;
            if(nullCounter>1)
                emit errorMsg("loopTroughUiItems NULL passed "+n(nullCounter)+" times.. Could use only once for initialization and set loading");
        }
    #endif


        bool found=0;

        for(auto &item:uiItems){

            if((target!=NULL && item.ptr!=target)||(item.writeLock&&op==uiOp::valFromUi)){
                continue;
            }else{
                found=1;
            }

            switch (item.type) {

            case spinBox:{
                QSpinBox*sBox=qobject_cast<QSpinBox*>(item.ptr);
                if (sBox != NULL){
                    int*p=(int*)item.valPtr;
                    switch (op){
                     case uiOp::valToUi:
                        sBox->setValue(valCorrection(*p,item,uiOp::valToUi));
                        continue;
                     case uiOp::valFromUi:
                        *p=valCorrection(sBox->value(),item);  ;
                        continue;
                     case uiOp::fileFromUi:
                         uiSet.setValue(sBox->objectName(), sBox->value());
                        continue;
                     case uiOp::fileToUiAndPtr:
                        sBox->setValue(uiSet.value(sBox->objectName()).toInt());
                        continue;
                    }
                }}
            case doubleSpinBox:{
                QDoubleSpinBox*dsBox=qobject_cast<QDoubleSpinBox*>(item.ptr);
                if (dsBox != NULL){
                    double*p=(double*)item.valPtr;
                    switch (op){
                     case uiOp::valToUi:
                        dsBox->setValue(valCorrection(*p,item,uiOp::valToUi));
                        continue;
                     case uiOp::valFromUi:
                        *p=valCorrection(dsBox->value(),item);
                        continue;
                     case uiOp::fileFromUi:
                         uiSet.setValue(dsBox->objectName(), dsBox->value());
                        continue;
                     case uiOp::fileToUiAndPtr:
                        dsBox->setValue(uiSet.value(dsBox->objectName()).toDouble());
                        continue;
                    }
                }}
            case checkBox:{
                QCheckBox*cBox=qobject_cast<QCheckBox*>(item.ptr);
                if (cBox != NULL){
                    bool*p=(bool*)item.valPtr;
                    switch (op){
                     case uiOp::valToUi:
                        cBox->setChecked(*p);
                        continue;
                     case uiOp::valFromUi:
                        *p=cBox->isChecked();
                        continue;
                     case uiOp::fileFromUi:
                         uiSet.setValue(cBox->objectName(), cBox->isChecked());
                        continue;
                     case uiOp::fileToUiAndPtr:
                        cBox->setChecked(uiSet.value(cBox->objectName()).toBool());
                        continue;
                    }
                }}

            case radioButton:{

                QRadioButton*rBut=qobject_cast<QRadioButton*>(item.ptr);
                if (rBut != NULL){
                    bool*p=(bool*)item.valPtr;
                    switch (op){
                     case uiOp::valToUi:
                        rBut->setChecked(*p);
                        continue;
                     case uiOp::valFromUi:
                        *p=rBut->isChecked();
                        continue;
                     case uiOp::fileFromUi:
                         uiSet.setValue(rBut->objectName(), rBut->isChecked());
                        continue;
                     case uiOp::fileToUiAndPtr:
                        rBut->setChecked(uiSet.value(rBut->objectName()).toBool());
                        continue;
                    }
                }
            }
            case dateTimeEdit:{

                QDateTimeEdit*dtEdit=qobject_cast<QDateTimeEdit*>(item.ptr);
                if (dtEdit != NULL){
                    QDateTime*p=(QDateTime*)item.valPtr;
                    switch (op){
                     case uiOp::valToUi:
                        dtEdit->setDateTime(*p);
                        continue;
                     case uiOp::valFromUi:
                        *p=dtEdit->dateTime();
                        continue;
                     case uiOp::fileFromUi:
                        uiSet.setValue(dtEdit->objectName(), dtEdit->dateTime());
                        continue;
                     case uiOp::fileToUiAndPtr:
                        dtEdit->setDateTime(uiSet.value(dtEdit->objectName()).toDateTime());
                        continue;
                    }
                }}
            default:{
                emit errorMsg("ui CaseNotDefined or type and passed ptr mismatch, nam: "+item.ptr->objectName());
                continue;
            }
            }

            if(!found)
               emit errorMsg("ui ptr not found , nam:"+item.ptr->objectName());


        }

         if(op==uiOp::fileToUiAndPtr){
             syncUiVals(NULL,uiOp::valFromUi);
             #ifdef QT_DEBUG
                  nullCounter--;
             #endif
         }

    }

    void ui_sync_and_save::syncSingleVal(){
         syncUiVals(sender());//should return ptr of signal caller widget
    }

    void ui_sync_and_save::saveUiValsToFile(QString path)
    {
        uiSet.setPath(QSettings::IniFormat,QSettings::UserScope, path);
        syncUiVals(NULL,uiOp::fileFromUi);
    }

    void ui_sync_and_save::loadUiValsFromFile(QString path)
    {
        uiSet.setPath(QSettings::IniFormat,QSettings::UserScope, path);
        syncUiVals(NULL,uiOp::fileToUiAndPtr);
    }

    bool ui_sync_and_save::setWriteLock(QObject *uiItem,bool lock)
    {
        for(auto &item:uiItems){
            if(item.ptr==uiItem){
              item.writeLock=lock;
              return 1;
            }
        }
        return 0;
    }



    template<typename V>
    V ui_sync_and_save::valCorrection(V val, uiItem &itm,uiOp op)
    {
            switch (itm.mathOp) {
            noCorrection:
            return val;
            add:
            if(op=valFromUi){
                return val-itm.mathVal;
            }else{
                return val+itm.mathVal;
            }
            rem:
            if(op=valFromUi){
                return val+itm.mathVal;
            }else{
                return val-itm.mathVal;
            }
            multip:
            if(op=valFromUi){
                return val/itm.mathVal;
            }else{
                return val*itm.mathVal;
            }
            div:
            if(op=valFromUi){
                return val*itm.mathVal;
            }else{
                return val/itm.mathVal;
            }

            }

    }

All help is welcome.

Chris Kawa · wrote on 1 Sept 2019, 17:32

Templates are instantiated at the call site, so their body needs to be available at that point. The error says it's not.
To fix this and as a general rule of thumb - move your template implementation to the header file.

Q139 · wrote on 1 Sept 2019, 20:06

Wonderful , also had some problems with using signals improperly.