I am trying to learn QT and wanted to set the text of a lineEdit when pressing a push button. I tried using this code
void Notepad::on_pushButton_10_clicked(){
Notepad::lineEdit -> setText("test");
}
but it does not work since lineEdit is not a member of Notepad. How do I reference lineEdit?
Your code will look something like below :
void Notepad::on_pushButton_10_clicked(){
ui->lineEdit->setText("test");
}
provided that you named the lineEdit Widget as the lineEdit.
Related
In a user setting page, in that window i want a combobox that once you have selected something it will change the text of a line edit. for example
someone chose patrick and than the text change to his address and phone number.
im suspecting the code will look something like this:
if Qcombobox == "patrick"{
QlineEdit_phone = "911"
}
i have started to use QT designer and im lost on how Iam connecting slot and signal with object also.
the slot to change the editline by the change of selection through a combobox look like:
void pagesetting::on_comboBox_activated(const QString &arg1)
{
if (arg1=="gmail"){
ui-> lineEdit_port -> setText("465");
ui -> lineEdit_host -> setText("smtp.gmail.com");
}
if (arg1=="yahoo"){
ui-> lineEdit_port -> setText("465");
ui -> lineEdit_host -> setText("smtp.mail.yahoo.com");
}
}
if you use qt designer you still need to delcare everything if you want to play with the object
I have created a Qdialog box using the Qt creator designer as shown below:
When I need to display it, I'm instantiate the class dialogoverwrite (.cpp, .h and .ui)
DialogOverwrite *OverwriteDialog = new DialogOverwrite;
OverwriteDialog->exec();
OverwriteOption = OverwriteDialog->result()
My issue is that I want to get the QDialogButtonBox result but I do not know how. the current code, returning the result of the OverwriteDialog but it's not returning any QDialogButtonBox::Yes, QDialogButtonBox::YesToAll ...
How to catch the QButtonGroup result and not the QDialog result.
In the same way, If I want to change the label value from "File(s) and/or Folder(s)" to another label, how to access to this QLabel ?
Thanks for your help
When you pressed QDialogButton it was emit signal clicked(QAbstractButton*) by catching this signal you can identify which action button pressed.
Please go through following link it would be help you.
Qt: How to implement QDialogButtonBox with QSignalMapper for non-standard button ??
Well the standard way to do this is to handle the result by connecting it. So you could do:
connect(this, SIGNAL(clickedDialogButton(QAbstractButton*)),
SLOT(dialogButton(QAbstractButton* aButton)));
Next you would create a function in your class called dialogButton (for example) and have that handle the result:
void MyUI::dialogButton(QAbstractButton* aButton) {
// Obtain the standard button
StandardButton button = buttonBox−>standardButton(button);
// Switch on the type of button
switch (button) {
case QDialogButtonBox::YesToAll:
// Do the thing you would like to do here
break;
// add some more cases?
}
}
You could also check for the signal given by the QButtonGroup. Something like: void QGroupButton::buttonClicked(QAbstractButton* button) would work in the same way.
I am writing a small QT gui application where there is a QLineEdit in my mainwindow.ui and I want to display the entered text in a separate dialog and or window when a button is pressed.
Now, I have stored the input in a variable, and I am also able to show this string on a label within this same mainwindow,
void MainWindow::on_GoButton_clicked()
{
QString mytext = ui->lineEdit_1->text();
ui->label_1->setText(mytext);
}
Now, I want to open a popup dialog (can be a window also), for example SecDialog;
SecDialog secdialog;
secdialog.setModal(true);
secdialog.exec();
and display the text of mainwindow->mytext string variable in a label of the SecDialog. How can I do that ??? I know it is a basic level question, but I think it will help clear lot of my doubts reagrding moving values of variables in between forms and classes.
Situation
So this is your situation:
From your code, the dialog is a modal dialog:
SecDialog secdialog;
//secdialog.setModal(true); // It's not needed since you already called exec(), and the
// dialog will be automatically set to be modal just like what
// document says in Chernobyl's answer
secdialog.exec();
Solution
To make the dialog display the text from the Window,
the concept is to pass the information(text) from the Window
to the dialog, and use a setter function from the dialog to display it.
Like Floris Velleman's answer, he passed the mytext string (by reference) to a customized dialog constructor and called the setter theStringInThisClass(myString) at once.
The implementation detail of this function is complemented by Chernobyl's answer (use the name setLabelText instead):
void SecDialog::setLabelText(QString str)
{
ui->label->setText(str); // this "ui" is the UI namespace of the dialog itself.
// If you create the dialog by designer, it's from dialog.ui
// Do not confuse with the ui from mainwindow.ui
}
Chernobyl suggested another way which calls the setter in the slot function and it bypasses the need of defining another constructor, but basically the concept is the same:
void MainWindow::on_GoButton_clicked()
{
QString mytext = ui->lineEdit_1->text();
ui->label_1->setText(mytext);
SecDialog secdialog;
secdialog.setLabelText(myText); // display the text in dialog
secdialog.exec();
}
Comment
I try to illustrate the concept as clear as possible, because from my previous experience on your question, you just "copy & paste" codes from answers and took them as your final solution, which is not right. So I hope this summary could help you understand the concept and then you may write your own code.
This task can be easy done with getter/setter method or with signal and slot, but setter is more suitable here. In SecDialog header:
public:
void setLabelText(QString str);
//in cpp
void SecDialog::setLabelText(QString str)
{
ui->label->setText(str);//it is label dialog
}
Usage:
secDialog.setLabelText(myText);
Also line where you set modal to true is not necessary because
This property holds whether show() should pop up the dialog as modal
or modeless. By default, this property is false and show() pops up the
dialog as modeless. Setting his property to true is equivalent to
setting QWidget::windowModality to Qt::ApplicationModal. exec()
ignores the value of this property and always pops up the dialog as
modal.
Assuming SecDialog is a custom class with an interface file as well you might want to pass it as a constructor argument or pass it by using another function.
So in the SecDialog constructor you could have something like:
SecDialog::SecDialog(QWidget* parent, const QString& myString)
: QDialog(parent),
theStringInThisClass(myString)
{}
And then you could call it like:
SecDialog secdialog(this, mytext);
I made another window pop up using:
SecondDialog object;
object.setModal(true);
object.exec();
I added a label on the second dialog using the design form editor. However I would like to use a QString variable from the original dialog to use for that label. Is that possible? And if so how would I do it? Any input would be greatly appreciated.
You should provide a name for the label in your second dialog. You can do it in the designer's Object inspector (upper right corner by default), left column. Then, create a method
void SecondDialog::SetLabelText (QString &text)
{
ui.myLabel->setText (text);
}
Then call it from the first dialog before exec'ing.
how can I make a QLabel to behave like a link? What I mean is that I'd like to be able to click on it and then this would invoke some command on it.
QLabel does this already.
Sample code:
myLabel->setText("Click Here!");
myLabel->setTextFormat(Qt::RichText);
myLabel->setTextInteractionFlags(Qt::TextBrowserInteraction);
myLabel->setOpenExternalLinks(true);
The answer from cmannnett85 is fine if you just want to open a URL when the link is clicked, and you are OK with embedding that URL in the text field of the label. If you want to do something slightly custom, do this:
QLabel * myLabel = new QLabel();
myLabel->setName("myLabel");
myLabel->setText("text");
myLabel->setTextInteractionFlags(Qt::TextBrowserInteraction);
Then you can connect the linkActivated signal of the label to a slot, and do whatever you want in that slot. (This answer assumes you have basic familiarity with Qt's signals and slots.)
The slot might look something like this:
void MainWindow::on_myLabel_linkActivated(const QString & link)
{
QDesktopServices::openUrl(QUrl("http://www.example.com/"));
}