QlineEdit with some default text for which cursor should not be moved?
Solution 1
I managed to do what you want by deriving a class from QLineEdit
as per following..
Constructor..
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);
}
Override 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);
}
Cursor position change event..
void QCustomLineEdit::onCursorPositionChanged(int /*oldPos*/, int newPos)
{
if(m_isPlaceHolderActive)
{
if(newPos != 0)
setCursorPosition(0);
}
}
Text change event..
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);
}
}
}
I have written it very hastily to just show you. Test it yourself and feel free to point any mistake(s) or optimization(s). Hope this helps.
Solution 2
In the constructor put
ui->lineEdit->setPlaceholderText("password");
ui->lineEdit->setReadOnly(1);
And in on_lineEdit_selectionChanged()
SLOT, put
ui->lineEdit->setText("");
ui->lineEdit->setEchoMode(QLineEdit::Password);
ui->lineEdit->setReadOnly(0);
Solution 3
I noticed this question has tag pyqt so I'll put an actual answer related to that tag for those actually looking for a python way instead of c++.
self.searchEditText = QtGui.QLineEdit()
self.searchEditText.setPlaceholderText("Search for word")
Solution 4
For question 1, in Qt 5.0 and higher, setPlaceholderText does what you want. https://codereview.qt-project.org/#change,45326
Mathan Kumar
Updated on July 09, 2022Comments
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Mathan Kumar almost 2 years
In QT, a created
lineEdit
shows a text using thesetText()
method.But the cursor is movable for the default text. I want the cursor should not be movable for the default text.
My
lineEdit
type has been set as password. Hence the default text('Password') is also displayed as '********'. Whenever user types the type has to be changed as password and when there is no text or until the user have not typed any text, thelineEdit
should display the plain text 'password'
Any idea to fix the above two issues?
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Mathan Kumar almost 12 yearsThanks spyke. setPlaceholderText() method works good. But whenever the qlineedit widget gets focussed or mouse clicked on qlineedit, default text get hidden. I want to display the default text even when the cursor is in the widget with the condition that the cursor should not be moved until the user type any text....
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Mathan Kumar almost 12 yearssetPlaceholderText() method works good. But whenever the qlineedit widget gets focussed or mouse clicked on qlineedit, default text get hidden. I want to display the default text even when the cursor is in the widget with the condition that the cursor should not be moved until the user type any text.
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ScarCode almost 12 yearsOk. Remove ui->lineEdit->setText(""); and ui->lineEdit->setEchoMode(QLineEdit::Password); from on_lineEdit_selectionChanged(). And add ui->lineEdit->setEchoMode(QLineEdit::Password); in on_lineEdit_textEdited()
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Mathan Kumar almost 12 years@Ammar : Can i set my lineedit cursor color black when my default text color is grey. Is tat possible?
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Ammar almost 12 years@user971306: If you see the source code of
QLineEdit::paintEvent()
then you will notice that cursor is drawn usingQTextLayout::drawCursor()
function, which uses current pen set inQPainter
, which istext-color
. So you can override thatpaintEvent()
and set the appropriatepen-color
before drawing cursor.. Bit tricky.. :) -
Rachcha over 10 yearsPlease describe in short here what is given in the link. If you want to help, you could put this link in a comment. This doesn't look really like an answer right now.
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answerSeeker about 7 yearsAny python way? I don't really know c++
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Shf about 7 yearsI would add that
setEchoMode(QLineEdit::Password)
is also works really well withsetPlaceholderText
since Qt 5.4 and higher as well