I need to create a login dialog like this 

[![enter image description here](https://i.stack.imgur.com/3MJEH.png)](https://i.stack.imgur.com/3MJEH.png) [![enter image description here](https://i.stack.imgur.com/Qrkwx.png)](https://i.stack.imgur.com/Qrkwx.png)

image files: `eyeOn.png`, `eyeOff.png`

Requirements:

* password is shown only when we CLICK AND HOLD the eyeOn icon (even when we click and hold and drag the mouse to area outside of the dialog, the password is still shown), when we release the mouse, password is covered again.
* while password is shown, the eye icon is eyeOn. While password is covered, the eye icon is eyeOff.

I have just built the layout.

```
QGridLayout *mainlogin = new QGridLayout();

QLabel *usernameLabel = new QLabel;
usernameLabel->setWordWrap(true);
usernameLabel->setText("Username");
mainlogin->addWidget(usernameLabel, 0, 0);

QComboBox *usernameLineEdit = new QComboBox;
usernameLineEdit->setEditable(true);
usernameLabel->setBuddy(usernameLineEdit);
mainlogin->addWidget(usernameLineEdit, 0, 1);

QLabel *capslockShow = new QLabel;
capslockShow->setWordWrap(true);
capslockShow->setText(" ");
mainlogin->addWidget(capslockShow, 1, 1);

QLabel *passwordLabel = new QLabel;
passwordLabel->setWordWrap(true);
passwordLabel->setText("Password");
mainlogin->addWidget(passwordLabel, 2, 0);
QLineEdit *passwordLineEdit = new QLineEdit;
passwordLineEdit->setEchoMode(QLineEdit::Password);
QAction *myAction = passwordLineEdit->addAction(QIcon(":/eyeOff.png"), QLineEdit::TrailingPosition);
passwordLabel->setBuddy(passwordLineEdit);
mainlogin->addWidget(passwordLineEdit, 2, 1);

```

What should I do next? Pls help me with code snippet.
['https://Stackoverflow.com/questions/51192832', 'https://Stackoverflow.com', 'https://Stackoverflow.com/users/4196709/']
The solution is to add a `QAction` to the `QLineEdit`, this will create a `QToolButton` that we can obtain from the `associatedWidgets()` (it will be the second widget since the first one is the one associated with `clearButton`). Already having the `QToolButton` you must use the `pressed` and `released` signal.

**passwordlineedit.h**

```
#ifndef PASSWORDLINEEDIT_H
#define PASSWORDLINEEDIT_H

#include <QAction>
#include <QLineEdit>
#include <QToolButton>

class PasswordLineEdit: public QLineEdit
{
public:
    PasswordLineEdit(QWidget *parent=nullptr);
private slots:
    void onPressed();
    void onReleased();
protected:
    void enterEvent(QEvent *event);
    void leaveEvent(QEvent *event);
    void focusInEvent(QFocusEvent *event);
    void focusOutEvent(QFocusEvent *event);
private:
    QToolButton *button;
};

#endif // PASSWORDLINEEDIT_H

```

**passwordlineedit.cpp**

```
#include "passwordlineedit.h"

PasswordLineEdit::PasswordLineEdit(QWidget *parent):
    QLineEdit(parent)
{
    setEchoMode(QLineEdit::Password);
    QAction *action = addAction(QIcon(":/eyeOff"), QLineEdit::TrailingPosition);
    button = qobject_cast<QToolButton *>(action->associatedWidgets().last());
    button->hide();
    button->setCursor(QCursor(Qt::PointingHandCursor));
    connect(button, &QToolButton::pressed, this, &PasswordLineEdit::onPressed);
    connect(button, &QToolButton::released, this, &PasswordLineEdit::onReleased);
}

void PasswordLineEdit::onPressed(){
    QToolButton *button = qobject_cast<QToolButton *>(sender());
    button->setIcon(QIcon(":/eyeOn"));
    setEchoMode(QLineEdit::Normal);
}

void PasswordLineEdit::onReleased(){
    QToolButton *button = qobject_cast<QToolButton *>(sender());
    button->setIcon(QIcon(":/eyeOff"));
    setEchoMode(QLineEdit::Password);
}

void PasswordLineEdit::enterEvent(QEvent *event){
    button->show();
    QLineEdit::enterEvent(event);
}

void PasswordLineEdit::leaveEvent(QEvent *event){
    button->hide();
    QLineEdit::leaveEvent(event);
}

void PasswordLineEdit::focusInEvent(QFocusEvent *event){
    button->show();
    QLineEdit::focusInEvent(event);
}

void PasswordLineEdit::focusOutEvent(QFocusEvent *event){
    button->hide();
    QLineEdit::focusOutEvent(event);
}

```

The complete example can be downloaded from the following [link](https://github.com/eyllanesc/stackoverflow/tree/master/questions/51192832).
Rather than trying to make use of the `QAction` returned by `QLineEdit::addAction` you could probably use a [`QWidgetAction`](http://doc.qt.io/qt-5/qwidgetaction.html) for this when combined with a suitable event filter...

```
class eye_spy: public QWidgetAction {
  using super = QWidgetAction;
public:
  explicit eye_spy (QLineEdit *control, QWidget *parent = nullptr)
    : super(parent)
    , m_control(control)
    , m_on(":/eyeOn")
    , m_off(":/eyeOff")
    , m_pixmap_size(50, 50)
    {
      m_label.setScaledContents(true);
      m_control->setEchoMode(QLineEdit::Password);
      m_label.setPixmap(m_off.pixmap(m_pixmap_size));
      m_label.installEventFilter(this);
      setDefaultWidget(&m_label);
    }
protected:
  virtual bool eventFilter (QObject *obj, QEvent *event) override
    {
      if (event->type() == QEvent::MouseButtonPress) {
        m_control->setEchoMode(QLineEdit::Normal);
        m_label.setPixmap(m_on.pixmap(m_pixmap_size));
      } else if (event->type() == QEvent::MouseButtonRelease) {
        m_control->setEchoMode(QLineEdit::Password);
        m_label.setPixmap(m_off.pixmap(m_pixmap_size));
      }
      return(super::eventFilter(obj, event));
    }
private:
  QLineEdit *m_control;
  QLabel     m_label;
  QIcon      m_on;
  QIcon      m_off;
  QSize      m_pixmap_size;
};

```

Now, rather than...

```
QAction *myAction = passwordLineEdit->addAction(QIcon(":/eyeOff.png"), QLineEdit::TrailingPosition);

```

Use...

```
eye_spy eye_spy(passwordLineEdit);
passwordLineEdit->addAction(&eye_spy, QLineEdit::TrailingPosition);

```

Seems to provide the desired behaviour.