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Qlineedit with some default text for which the cursor should not move?

QT creates a line with text using the setText () method.

  • But the cursor moves for the default text. I want the cursor to not be able to move for the default text.

  • my lineedit type is set as password. Therefore, the default text (“Password”) also appears as “********”. Whenever a user enters a type, it must be changed as a password, and when there is no text or until the user has typed some text, qlineedit should display the plain text “password”

Any idea to fix the two above issues? enter image description here

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4 answers

, , QLineEdit .

..

QCustomLineEdit::QCustomLineEdit(QWidget *parent) :
    QLineEdit(parent)
{
    connect(this, SIGNAL(textChanged(QString)), this, SLOT(onTextChanged(QString)));
    connect(this, SIGNAL(cursorPositionChanged(int,int)), this, SLOT(onCursorPositionChanged(int,int)));

    setEchoMode(QLineEdit::Password);   // Echo mode in your case..

    m_echoMode = echoMode();            // Member variable to store original echo mode..
    m_placeHolderText = "Password";     // Member variable..
    m_isPlaceHolderActive = true;       // Member varible..

    // Default case..
    setPlaceholderText("");
    setStyleSheet("QCustomLineEdit{color: gray;}");
    setEchoMode(QLineEdit::Normal);
    setText(__placeHolderText);
}

keyPressEvent..

void QCustomLineEdit::keyPressEvent(QKeyEvent *e)
{
    if(m_isPlaceHolderActive)
    {
        if(e->key() == Qt::Key_Delete || e->key() == Qt::Key_Backspace)
            e->accept();
        else
            QLineEdit::keyPressEvent(e);

        return;
    }

    QLineEdit::keyPressEvent(e);
}

.

void QCustomLineEdit::onCursorPositionChanged(int /*oldPos*/, int newPos)
{
    if(m_isPlaceHolderActive)
    {
        if(newPos != 0)
            setCursorPosition(0);
    }
}

.

void QCustomLineEdit::onTextChanged(const QString &text)
{
    if(m_isPlaceHolderActive)
    {
        if(text.compare(m_placeHolderText) != 0)
        {
            m_isPlaceHolderActive = false;

            // Remove the 'placeHolderText' from 'text' itself..
            QString temp = text;
            temp = temp.mid(0, text.lastIndexOf(m_placeHolderText));

            setStyleSheet("QCustomLineEdit{color: black;}");
            setEchoMode(m_echoMode);
            setText(temp);
        }
        else
        {
            setEchoMode(QLineEdit::Normal);
            setText(m_placeHolderText);
            setStyleSheet("QCustomLineEdit{color: gray;}");
            setCursorPosition(0);
        }
    }
    else
    {
        if(text.isEmpty())
        {
            m_isPlaceHolderActive = true;
            setStyleSheet("QCustomLineEdit{color: gray;}");
            setEchoMode(QLineEdit::Normal);
            setText(m_placeHolderText);
        }
    }
}

, . (). , .

+3

ui->lineEdit->setPlaceholderText("password");
ui->lineEdit->setReadOnly(1);

on_lineEdit_selectionChanged() SLOT

ui->lineEdit->setText("");
ui->lineEdit->setEchoMode(QLineEdit::Password);
ui->lineEdit->setReadOnly(0);
+6

1, Qt 5.0 , setPlaceholderText , . https://codereview.qt-project.org/#change,45326

+2

, pyqt, , , , python ++.

self.searchEditText = QtGui.QLineEdit()
self.searchEditText.setPlaceholderText("Search for word")
+2

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