how to work with data from two .cpp

Question

Created a project that consists of two windows: in the first window we fill in variables, in the second we display the filled variables. In one executable file (dialog.cpp), I take variables and set parameters for them, take them from the header file (peremennie1.h). After filling them in, I want to output them in an executable file (mainwindow.cpp), BUT this does not happen, they are completely zeroed 0_o.

What am I doing wrong ????

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Here is the whole code, it is very simple there are three buttons and a couple of lines of code, the main thing for me is to understand the mechanism.

File welik_oshibka.pro

QT += core gui greaterThan(QT_MAJOR_VERSION, 4): QT += widgets TARGET = welik_oshibka TEMPLATE = app SOURCES += main.cpp\ mainwindow.cpp \ dialog.cpp \ peremennie1.cpp HEADERS += mainwindow.h \ dialog.h \ peremennie1.h FORMS += mainwindow.ui \ dialog.ui

Peremennie1.h file

  #ifndef PEREMENNIE1_H #define PEREMENNIE1_H class peremennie1 { public: // peremennie1(); explicit peremennie1(); virtual ~peremennie1(); int WRE ; int WRE_PR; int wre_izL; double WRE_DABL; int *K2I_IZ; }; #endif // PEREMENNIE1_H

peremennie1.cpp

  #include "peremennie1.h" peremennie1::peremennie1() { WRE = 0; WRE_PR = 0; wre_izL = 0; WRE_DABL = 0; // массивчик K2I_IZ=0; } peremennie1::~peremennie1() { if(K2I_IZ) delete []K2I_IZ; }

Dialog.h file

 #ifndef DIALOG_H #define DIALOG_H #include <QDialog> namespace Ui { class Dialog; } class Dialog : public QDialog { Q_OBJECT public: explicit Dialog(QWidget *parent = 0); ~Dialog(); private slots: void on_pushButton_clicked(); void on_pushButton_2_clicked(); signals: void signal_dialog_show(); private: Ui::Dialog *ui; }; #endif // DIALOG_H

Dialog.cpp file

 #include "dialog.h" #include "ui_dialog.h" #include "peremennie1.h" #include "QDebug" peremennie1 per; Dialog::Dialog(QWidget *parent) : QDialog(parent), ui(new Ui::Dialog) { ui->setupUi(this); } Dialog::~Dialog() { delete ui; } void Dialog::on_pushButton_clicked() { qDebug() << "per.WRE = " << per.WRE; qDebug() << "per.WRE_PR =" << per.WRE_PR; qDebug() << "per.wre_izL =" << per.wre_izL; qDebug() << "per.WRE_DABL =" << per.WRE_DABL; emit signal_dialog_show(); this->hide(); } void Dialog::on_pushButton_2_clicked() { // тут заполняем данные per.WRE = 25; per.WRE_PR = 26; per.wre_izL = 27; per.WRE_DABL = 28.55; ui->label->setText("zapolnili"); }

Main.cpp file

 #include "mainwindow.h" #include <QApplication> int main(int argc, char *argv[]) { QApplication a(argc, argv); MainWindow w; // w.show(); return a.exec(); }

Mainwindows.h file

  #ifndef MAINWINDOW_H #define MAINWINDOW_H #include <QMainWindow> namespace Ui { class MainWindow; } class MainWindow : public QMainWindow { Q_OBJECT public: explicit MainWindow(QWidget *parent = 0); ~MainWindow(); public slots: void select_peremennie1(); private slots: void on_pushButton_clicked(); void on_pushButton_2_clicked(); void on_pushButton_3_clicked(); private: Ui::MainWindow *ui; }; #endif // MAINWINDOW_H

Mainwindows.cpp file

 #include "mainwindow.h" #include "ui_mainwindow.h" #include "dialog.h" #include "peremennie1.h" #include "QDebug" Dialog *glsso1_d = 0; peremennie1 *per = new peremennie1; MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent), ui(new Ui::MainWindow) { ui->setupUi(this); // this->hide(); // Инициализировать диалоги выбора режима и типа антенны glsso1_d = new Dialog(this); glsso1_d->show(); qDebug() << "!!!per->WRE = " << per->WRE; qDebug() << "!!!per->WRE_PR =" << per->WRE_PR; qDebug() << "!!!per->wre_izL =" << per->wre_izL; qDebug() << "!!!per->WRE_DABL =" << per->WRE_DABL; // штука что бы прыгать между кнопками connect(glsso1_d, SIGNAL(signal_dialog_show()), this, SLOT(select_peremennie1())); } // выбирается режим в котором будет работать основной блок программы void MainWindow::select_peremennie1() { this->show(); } MainWindow::~MainWindow() { delete ui; } void MainWindow::on_pushButton_clicked() { // возвращаем диалог glsso1_d->show(); this->hide(); } void MainWindow::on_pushButton_2_clicked() { ui->spinBox->setValue(per->WRE); ui->spinBox_2->setValue(per->WRE_PR); ui->spinBox_3->setValue(per->wre_izL); ui->doubleSpinBox->setValue(per->WRE_DABL); } void MainWindow::on_pushButton_3_clicked() { qDebug() << "!!!+_+!!!per->WRE = " << per->WRE; qDebug() << "!!!+_+!!!per->WRE_PR =" << per->WRE_PR; qDebug() << "!!!+_+!!!per->wre_izL =" << per->wre_izL; qDebug() << "!!!+_+!!!per->WRE_DABL =" << per->WRE_DABL; }

Dialog.ui file

 <?xml version="1.0" encoding="UTF-8"?> <ui version="4.0"> <class>Dialog</class> <widget class="QDialog" name="Dialog"> <property name="geometry"> <rect> <x>0</x> <y>0</y> <width>305</width> <height>352</height> </rect> </property> <property name="windowTitle"> <string>Dialog</string> </property> <widget class="QPushButton" name="pushButton"> <property name="geometry"> <rect> <x>80</x> <y>60</y> <width>111</width> <height>41</height> </rect> </property> <property name="text"> <string>задаем данные</string> </property> </widget> <widget class="QPushButton" name="pushButton_2"> <property name="geometry"> <rect> <x>80</x> <y>150</y> <width>111</width> <height>71</height> </rect> </property> <property name="text"> <string>заполняем данные</string> </property> </widget> <widget class="QLabel" name="label"> <property name="geometry"> <rect> <x>90</x> <y>260</y> <width>111</width> <height>31</height> </rect> </property> <property name="text"> <string/> </property> </widget> </widget> <resources/> <connections/> </ui>

Mainwindows.ui file

 <?xml version="1.0" encoding="UTF-8"?> <ui version="4.0"> <class>MainWindow</class> <widget class="QMainWindow" name="MainWindow"> <property name="geometry"> <rect> <x>0</x> <y>0</y> <width>400</width> <height>300</height> </rect> </property> <property name="windowTitle"> <string>MainWindow</string> </property> <widget class="QWidget" name="centralWidget"> <widget class="QPushButton" name="pushButton"> <property name="geometry"> <rect> <x>40</x> <y>20</y> <width>101</width> <height>51</height> </rect> </property> <property name="text"> <string>возвращение</string> </property> </widget> <widget class="QPushButton" name="pushButton_2"> <property name="geometry"> <rect> <x>40</x> <y>110</y> <width>75</width> <height>23</height> </rect> </property> <property name="text"> <string>вывод</string> </property> </widget> <widget class="QLabel" name="label"> <property name="geometry"> <rect> <x>160</x> <y>100</y> <width>61</width> <height>21</height> </rect> </property> <property name="text"> <string>WRE</string> </property> </widget> <widget class="QLabel" name="label_2"> <property name="geometry"> <rect> <x>160</x> <y>130</y> <width>71</width> <height>21</height> </rect> </property> <property name="text"> <string>WRE_PR</string> </property> </widget> <widget class="QLabel" name="label_3"> <property name="geometry"> <rect> <x>160</x> <y>160</y> <width>61</width> <height>21</height> </rect> </property> <property name="text"> <string>WRE_izl</string> </property> </widget> <widget class="QLabel" name="label_4"> <property name="geometry"> <rect> <x>160</x> <y>190</y> <width>71</width> <height>21</height> </rect> </property> <property name="text"> <string>WRE_DABL</string> </property> </widget> <widget class="QSpinBox" name="spinBox"> <property name="enabled"> <bool>false</bool> </property> <property name="geometry"> <rect> <x>250</x> <y>100</y> <width>42</width> <height>22</height> </rect> </property> </widget> <widget class="QSpinBox" name="spinBox_2"> <property name="enabled"> <bool>false</bool> </property> <property name="geometry"> <rect> <x>250</x> <y>130</y> <width>42</width> <height>22</height> </rect> </property> </widget> <widget class="QSpinBox" name="spinBox_3"> <property name="enabled"> <bool>false</bool> </property> <property name="geometry"> <rect> <x>250</x> <y>160</y> <width>42</width> <height>22</height> </rect> </property> </widget> <widget class="QDoubleSpinBox" name="doubleSpinBox"> <property name="enabled"> <bool>false</bool> </property> <property name="geometry"> <rect> <x>240</x> <y>190</y> <width>62</width> <height>22</height> </rect> </property> </widget> <widget class="QPushButton" name="pushButton_3"> <property name="geometry"> <rect> <x>40</x> <y>150</y> <width>75</width> <height>23</height> </rect> </property> <property name="text"> <string>разведка</string> </property> </widget> </widget> <widget class="QMenuBar" name="menuBar"> <property name="geometry"> <rect> <x>0</x> <y>0</y> <width>400</width> <height>21</height> </rect> </property> </widget> <widget class="QToolBar" name="mainToolBar"> <attribute name="toolBarArea"> <enum>TopToolBarArea</enum> </attribute> <attribute name="toolBarBreak"> <bool>false</bool> </attribute> </widget> <widget class="QStatusBar" name="statusBar"/> </widget> <layoutdefault spacing="6" margin="11"/> <resources/> <connections/> </ui>

Alexey Sarovsky Alexey Sarovsky 1,325 6 15 · Answer 1 · 2017-03-02T14:07:18

When you include a header file, this is, if roughly, a simple substitution of the entire file into the place where the include directive is written. That is, included in two places, in two places you had the string int var; . To use the same variable in several places, you need to declare it in one place as usual ( int var; ), and in others extern int var; Something like this.

Do not be offended at me please, but this is not the answer.
You did not say where to insert this code and how to insert it.
For example, to build a ship for flights between the stars, you need to install a nuclear star engine there.
Just wherever I tried to shove it extern everywhere he gave me an error

Answer 2 · 2017-03-02T14:07:31

In different translation units (read .cpp files) you work with different instance variables of the peremennie1 class.

In dialog.cpp you define one global variable:

 peremennie1 per;

and in mainwindows.cpp - the second (and for some reason you place it in the "heap"):

 peremennie1 *per = new peremennie1;

Define this variable somewhere in one place and access it from different objects.

For example, define your variable in the function main and pass it to your MainWindow object:

 int main(int argc, char *argv[]) { QApplication a(argc, argv); peremennie1 per; MainWindow w; w.setContext(&per); w.show(); return a.exec(); }

Define the setContext(peremennie1* per) method setContext(peremennie1* per) and the field peremennie1* m_per in the MainWindow class:

 class Mainwindow ... { private: peremennie1* m_per = nullptr; ... public: void setContext(peremennie1* per) { m_per = per; } };

Further from the MainWindow methods, access this variable via the local m_per pointer.

You can pass this variable to your Dialog class in a similar way.

How would I understand what you are saying but I do not understand how to do it.

timob256 timob256 1.219 one ten 32 · Accepted Answer · 2017-03-02T16:14:07

aleks.andr and Alexey Sarovsky thank you for your answers. But I still give a detailed answer.

in peremennie1.h

  #ifndef PEREMENNIE1_H #define PEREMENNIE1_H class peremennie1 { public: // peremennie1(); explicit peremennie1(); virtual ~peremennie1(); int WRE ; int WRE_PR; int wre_izL; double WRE_DABL; int *K2I_IZ; }; extern peremennie1 per;

In the dialog.cpp file, replace the code (with this: 3)

 #include "dialog.h" #include "ui_dialog.h" #include "peremennie1.h" #include "mainwindow.h" #include "QDebug" Dialog::Dialog(QWidget *parent) : QDialog(parent), ui(new Ui::Dialog) { ui->setupUi(this); } Dialog::~Dialog() { delete ui; } void Dialog::on_pushButton_clicked() { qDebug() << "per.WRE = " << per.WRE; qDebug() << "per.WRE_PR =" << per.WRE_PR; qDebug() << "per.wre_izL =" << per.wre_izL; qDebug() << "per.WRE_DABL =" << per.WRE_DABL; emit signal_dialog_show(); this->hide(); } void Dialog::on_pushButton_2_clicked() { // тут заполняем данные per.WRE = 25; per.WRE_PR = 26; per.wre_izL = 27; per.WRE_DABL = 28.55; ui->label->setText("zapolnili"); }

In the mainwindow.cpp file

delete the line

 peremennie1 *per = new peremennie1;

And replace the strings with the call per-> WRE with this variant per.WRE.

Example: It was

 void MainWindow::on_pushButton_2_clicked() { ui->spinBox->setValue(per->WRE); ui->spinBox_2->setValue(per->WRE_PR); ui->spinBox_3->setValue(per->wre_izL); ui->doubleSpinBox->setValue(per->WRE_DABL); } void MainWindow::on_pushButton_3_clicked() { qDebug() << "!!!+_+!!!per->WRE = " << per->WRE; qDebug() << "!!!+_+!!!per->WRE_PR =" << per->WRE_PR; qDebug() << "!!!+_+!!!per->wre_izL =" << per->wre_izL; qDebug() << "!!!+_+!!!per->WRE_DABL =" << per->WRE_DABL; }

It became

 void MainWindow::on_pushButton_2_clicked() { ui->spinBox->setValue(per.WRE); ui->spinBox_2->setValue(per.WRE_PR); ui->spinBox_3->setValue(per.wre_izL); ui->doubleSpinBox->setValue(per.WRE_DABL); } void MainWindow::on_pushButton_3_clicked() { qDebug() << "!!!+_+!!!per.WRE = " << per.WRE; qDebug() << "!!!+_+!!!per.WRE_PR =" << per.WRE_PR; qDebug() << "!!!+_+!!!per.wre_izL =" << per.wre_izL; qDebug() << "!!!+_+!!!per.WRE_DABL =" << per.WRE_DABL; }

how to work with data from two .cpp

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