QPointerEvent throws error

Christian Ehrlicher

@curiosity said in QPointerEvent throws error:

void onCurrentTextChanged(const QString &text)...

This is a free function... How does this even compile?

Please provide your full relevant code which actually compiles.

curiosity

@Christian-Ehrlicher
but i am using this as a slot. Please check the connect statement

Christian Ehrlicher

void MainWindow::onCurrentTextChanged() and void onCurrentTextChanged() are two different functions. Provide your full code including the header.

curiosity

This post is deleted!

Christian Ehrlicher

And now please format your code with the code (</>) tags so it is readable for others.
Your header does not match the source - this does not compile. And then you have a local variable echoLabel but connect the member later on...

curiosity

@Christian-Ehrlicher
//NewWidget.cpp

#include "NewWidget.h"
#include <iostream>
using namespace std;

#include <QComboBox>
#include <QGridLayout>
#include <QGroupBox>
#include <QLabel>
#include <QLineEdit>
#include <QtWidgets>


Window::Window(QWidget *parent) QWidget(parent)
{
    QGroupBox *echoGroup = new QGroupBox(tr("Echo"));

QLabel *echoLabel = new QLabel(tr("Mode:"));
QComboBox *echoComboBox = new QComboBox;
echoComboBox->addItem(tr("Normal"));
echoComboBox->addItem(tr("Password"));
echoComboBox->addItem(tr("PasswordEchoOnEdit"));
echoComboBox->addItem(tr("No Echo"));


echoLineEdit = new QLineEdit;
echoLineEdit->setPlaceholderText("Placeholder Text");

QLabel *passwordLabel = new QLabel(tr("Password entered is :"));
passwordLineEdit = new QLineEdit;

QGroupBox *validatorGroup = new QGroupBox(tr("Validator"));

QLabel *validatorLabel = new QLabel(tr("Type:"));
QComboBox *validatorComboBox = new QComboBox;
validatorComboBox->addItem(tr("No validator"));
validatorComboBox->addItem(tr("Integer validator"));
validatorComboBox->addItem(tr("Double validator"));

validatorLineEdit = new QLineEdit;
validatorLineEdit->setPlaceholderText("Placeholder Text");

QGroupBox *alignmentGroup = new QGroupBox(tr("Alignment"));

QLabel *alignmentLabel = new QLabel(tr("Type:"));
QComboBox *alignmentComboBox = new QComboBox;
alignmentComboBox->addItem(tr("Left"));
alignmentComboBox->addItem(tr("Centered"));
alignmentComboBox->addItem(tr("Right"));

alignmentLineEdit = new QLineEdit;
alignmentLineEdit->setPlaceholderText("Placeholder Text");/>

connect(echoComboBox,&QComboBox::editTextChanged, this, &Window::onCurrentTextChanged);

connect(validatorComboBox, static_cast<void (QComboBox::*)(int)>(&QComboBox::activated),this, &Window::validatorChanged);
connect(alignmentComboBox, static_cast<void (QComboBox::*)(int)>(&QComboBox::activated), this, &Window::alignmentChanged);

QGridLayout *echoLayout = new QGridLayout;
echoLayout->addWidget(echoLabel, 0, 0);
echoLayout->addWidget(echoComboBox, 0, 1, Qt::AlignLeft);
echoLayout->addWidget(echoLineEdit, 1, 0, 1, 2);
echoLayout->addWidget(passwordLabel, 2, 0);
echoLayout->addWidget(passwordLineEdit, 2, 2, 1, 2 );
echoLayout->setRowStretch(0, 5);
echoGroup->setLayout(echoLayout);

QGridLayout *validatorLayout = new QGridLayout;
validatorLayout->addWidget(validatorLabel, 0, 0);
validatorLayout->addWidget(validatorComboBox, 0, 1);
validatorLayout->addWidget(validatorLineEdit, 1, 0, 1, 2);
validatorGroup->setLayout(validatorLayout);

QGridLayout *alignmentLayout = new QGridLayout;
alignmentLayout->addWidget(alignmentLabel, 0, 0);
alignmentLayout->addWidget(alignmentComboBox, 0, 1);
alignmentLayout->addWidget(alignmentLineEdit, 1, 0, 1, 2);
alignmentGroup-> setLayout(alignmentLayout);


QGridLayout *grid = new QGridLayout;
grid->addWidget(createFirstGroup(), 0, 1);
grid->heightForWidth(10);
grid->setRowStretch(0,50);

//setWindowTitle(tr("Radio Buttons"));


QGridLayout *layout = new QGridLayout;
layout->addWidget(echoGroup, 0, 0);
layout->addWidget(validatorGroup, 1, 0);
layout->addWidget(alignmentGroup, 2, 0);
layout->addWidget(createFirstGroup(), 0, 1);
//layout->addWidget(accessGroup, 1, 1);
setLayout(layout);

setWindowTitle(tr("Line Edits"));

}

QGroupBox *Window::createFirstGroup()
{
    QGroupBox *groupBox = new QGroupBox(tr("Radio Buttons group"));

    QRadioButton *radio1 = new QRadioButton(tr("&Radio button 1"));
    QRadioButton *radio2 = new QRadioButton(tr("R&adio button 2"));
    QRadioButton *radio3 = new QRadioButton(tr("Ra&dio button 3"));

    radio1->setChecked(true);

    QVBoxLayout *vbox = new QVBoxLayout;
    vbox->addWidget(radio1);
    vbox->addWidget(radio2);
    vbox->addWidget(radio3);
    vbox->addStretch(1);
    groupBox->setLayout(vbox);
    resize(100, 200);

    return groupBox;
}

void Window::echoChanged(int index)
{
    switch (index) {
    case 0:
        echoLineEdit->setEchoMode(QLineEdit::Normal);
        break;
    case 1:
        echoLineEdit->setEchoMode(QLineEdit::Password);
        break;
    case 2:
        echoLineEdit->setEchoMode(QLineEdit::PasswordEchoOnEdit);
        break;
    case 3:
        echoLineEdit->setEchoMode(QLineEdit::NoEcho);
        break;
    }
}

void Window::validatorChanged(int index)
{
    switch (index) {
    case 0:
        validatorLineEdit->setValidator(nullptr);
        break;
    case 1:
        validatorLineEdit->setValidator(new QIntValidator(
            validatorLineEdit));
        break;
    case 2:
        validatorLineEdit->setValidator(new QDoubleValidator(-999.0,
            999.0, 2, validatorLineEdit));
        break;
    }

    validatorLineEdit->clear();
}

void Window::alignmentChanged(int index)
{
    switch (index) {
    case 0:
        alignmentLineEdit->setAlignment(Qt::AlignLeft);
        break;
    case 1:
        alignmentLineEdit->setAlignment(Qt::AlignCenter);
        break;
    case 2:
        alignmentLineEdit->setAlignment(Qt::AlignRight);
        break;
    }
}

void Window::onCurrentTextChanged(const QString &text)
{
qDebug() << QString(" entered text is ")<< text;
passwordLineEdit->setPlaceholderText("Password entered is : ");
passwordLineEdit->setText(text);
passwordLineEdit->show();
passwordLineEdit->setEchoMode(QLineEdit::PasswordEchoOnEdit);
}

curiosity

@Christian-Ehrlicher

I tried formatting it. but this was how it shoed up after posting NewWidget.cpp

#ifndef WINDOW_H
#define WINDOW_H

#include <QWidget>
#include <QLineEdit>
#include <QDebug>

QT_BEGIN_NAMESPACE
class QLineEdit;
class QGroupBox;
QT_END_NAMESPACE


class Window : public QWidget
{
    Q_OBJECT

public:
    QLineEdit *passwordLineEdit;

    Window(QWidget *parent = nullptr);

private:
    QLineEdit *echoLineEdit;
    QLineEdit *validatorLineEdit;
    QLineEdit *alignmentLineEdit;

public slots:
    void echoChanged(int);
    void validatorChanged(int);
    void alignmentChanged(int);
    QGroupBox *createFirstGroup();

};

#endif

//Main.cpp

#include <QApplication>

#include "NewWidget.h"

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);
    Window window;
    window.show();
    return app.exec();
}

code is compiling and running.. except that it is not echoing the text entered

Christian Ehrlicher

Please read my post carefully and fix the errors in your code.

Christian Ehrlicher

This post is deleted!

JonB

@curiosity
There is an awful lot of code (and discussion) here, I am lost as to where you are at. In the following order:

connect(echoComboBox,&QComboBox::editTextChanged, this, [](const QString &text) { qDebug() << "text:" << text; } );
Does this work?
connect(echoComboBox,&QComboBox::editTextChanged, this, &Window::onCurrentTextChanged);
Where Window::onCurrentTextChanged(const QString &text) slot has qDebug() << "text:" << text; as its first statement.
Does this work?
Once those are working. If text does not show from passwordLineEdit->setText(text); where you have gone passwordLineEdit->setEchoMode(QLineEdit::PasswordEchoOnEdit); try without PasswordEchoOnEdit, I don't know if that interferes with what you can do or see when you mark a line edit as being for password entry.

Christian Ehrlicher

@JonB It can not work. See my comment about local and member variable. C++ basic stuff.

JonB

@Christian-Ehrlicher
Hi Christian. Per your comment I did try searching this page for echoLabel (got a bit confused in the formatting), I thought I saw it was a local newed variable. But that's not to do with connecting?

Did you mean echoCombobox? But that is also newed and in scope when connect()ed, and I did not come across a member variable of that name instead? Maybe I mis-searched....

Maybe I should leave you to it, you have perhaps copied the code and played with it.

Christian Ehrlicher

@JonB You might be right. The code formatting (and useless reposting instead editing the former post) and the difference between the source and the header which makes the whole stuff uncompilable as the header is missing the slot definition for onCurrentTextChanged() confused me. Wonder (every time again) what's so hard writing a minimal and compileable example.

JonB

@Christian-Ehrlicher
If you are correct OP will not even get past my point #1. That is why I suggest they follow those in order and we will know where they do/do not get to :)

curiosity

@Christian-Ehrlicher @JonB
sorry for the typos.. please read as the " this was how it showed*** up after posting NewWidget.cpp

JonB

@curiosity I don't know where you are at now, but if you answer where you get to in the 3 steps I suggested earlier we may know where whatever issue lies.

curiosity

@JonB

your point 1 isnt working.. i have a break point inside my connect statement and i tried debugging.

i have following error

"mincore\com\oleaut32\dispatch\ups.cpp(2122)\OLEAUT32.dll!00007FFCE48BA726: (caller: 00007FFCE48B9B39) ReturnHr(1) tid(3250) 8002801D Library not registered."

   QObject::connect(echoComboBox, &QComboBox::currentTextChanged, this,  [&](const QString &text) {
       qDebug() << "text:" << text;/* i have a breakpoint here which is not getting hit also text is not printed to console*/
         Window::onCurrentTextChanged(text);

       echoLineEdit->show();
   });

curiosity

@JonB
Its working now.. the signal was emitted from QCombobox.but it should have been

   QObject::connect(echoLineEdit, &QLineEdit::textChanged, this,  [&](const QString &text) {
       Window::onCurrentTextChanged(text);
       echoLineEdit->show();
   });

Now it is working as expected

Pl45m4

@curiosity said in QPointerEvent throws error:

Now it is working as expected

Great, then mark the topic as solved.

Beside the discussion about syntax and other stuff and I believe it was mentioned here before....
your lambda is not needed and the content does not make too much sense.

Window::onCurrentTextChanged(text);

In what scope this is called? If you are in Window and you pass this to your labda, you don't need the fully qualified function name.

echoLineEdit->show();

Calling show() after the text has changed is not needed unless you never insert text manully but always set text programmatically with setText(...).
But even then, connecting to slot onCurrentTextChanged(text) in Window would be way easier.

curiosity

@Pl45m4

if you say that lambda is not needed, in which context do we use lambda for connect statements