Changing a label in Qt
I'm trying to make a simple program consisting of a button and a label. When the button is pressed, it should change the label text to whatever is in a QString variable inside the program. Here's my code so far:
This is my widget.h file:
class Widget : public QWidget
{
Q_OBJECT
public:
Widget(QWidget *parent = 0);
~Widget();
private:
Ui::WidgetClass *ui;
QString test;
private slots:
void myclicked();
};
And here's the implementation of the Widget class:
#include "widget.h"
#in开发者_StackOverflowclude "ui_widget.h"
Widget::Widget(QWidget *parent)
: QWidget(parent), ui(new Ui::WidgetClass)
{
ui->setupUi(this);
test = "hello world";
connect(ui->pushButton, SIGNAL(clicked()), ui->label, SLOT(myclicked()));
}
Widget::~Widget()
{
delete ui;
}
void Widget::myclicked(){
ui->label->setText(test);
}
It runs but when the button is clicked, nothing happens. What am I doing wrong?
Edit: after i got it working, the text in the label was larger than the label itself, so the text got clipped. I fixed it by adding ui->label->adjustSize()
to the definition of myclicked().
You are connecting the signal to the wrong object. myclicked() is not a slot of QLabel, it is a slot of your Widget class. The connection string should be:
connect(ui->pushButton, SIGNAL(clicked()), this, SLOT(myclicked()));
Take a look at the console output of your program. There should be an error message saying something like:
Error connecting clicked() to myclicked(): No such slot defined in QLabel
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