Ultra newbie Signal Slot question
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Hi,
Done lots of RTFM, but would hugely appreciate a tiny bit of starter code which would help me get my head around signals and slots.
I have a QString variable in my app class, and an LineEdit widget in the ui. Call these myString and myLineEdit.
I'd like to set up a two-way link as follows: if the user edits the string in the UI, myString should be updated accordingly. Likewise, I'd like a function, e.g. SetString(QString newString) which can be called by other code - updating myString and updating the displayed text in myLineEdit.
The first part I can handle I think, the second part presumably means I have to get 'SetString' to emit a signal which needs to be connected to a slot of myLineEdit. (?)
Struggling somewhat to work out both syntax and best-practice - any advice most welcome, thanks in advance.
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@
class MyClass : public QWidget
{
Q_OBJECT
// ...
public slots:
void setString(const QString &newString);
QString getString() const;signals:
// optional:
myStringChanged(const QString &newString);protected:
QString myString;
}// Now, .cpp file:
MyClass::MyClass(QWidget *parent) : QWidget(parent)
{
connect(myLineEdit, SIGNAL(textChanged(QString)), this, SLOT(setString(QString));
}MyClass::setString(const QString &string)
{
myString = string;if (myLineEdit.text() != string) {
myLineEdit.blockSignals(true);
myLineEdit.setText(string);
myLineEdit.blockSignals(false);
}
}
@This should do all you wanted to be done :) This is of course only one of many ways to do the job.
