Error in changing the colour of the item of a listwidget

[Ahmed Abdellatif]

I am trying to do some operation of the selected item in a list widget if a pushbutton is clicked. this is done using the following code

void Dialog::on_pushButton_clicked()
{
    if(MyListWidget->currentItem()->isSelected())
    {
        MyListWidget->currentItem()->setText("YOU");
        QString my_text= MyListWidget->currentItem()->text();
        qDebug()<<my_text;
 
        MyListWidget->currentItem()->setBackgroundColor(Qt::green);
    }
    else return;
}

void Dialog::on_pushButton_clicked()
{
    if(MyListWidget->currentItem()->isSelected())
    {
        MyListWidget->currentItem()->setText("YOU");
        QString my_text= MyListWidget->currentItem()->text();
        qDebug()<<my_text;

        MyListWidget->currentItem()->setBackgroundColor(Qt::green);
    }
    else return;
}

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The program works well if we select an item before pressing the pushbutton,the problem occurs if no item is selected before clicking the button, the programme is crashed

[admkrk]

What happens if you just remove the else statement?

[Ginsengelf]

Hi, just guessing, but I think MyListWidget->currentItem() will return NULL.

A debugger will help you to determine the position and reason of the crash.

Ginsengelf

[high_flyer]

Try this:

void Dialog::on_pushButton_clicked()
{
    QListWidgetItem *pCurrItem = MyListWidget->currentItem();
    if(pCurrItem && pCurrItem->isSelected())
    {
        pCurrItem->setText("YOU");
        QString my_text= pCurrItem->text();
        qDebug()<<my_text;
 
        pCurrItem->setBackgroundColor(Qt::green);
    }   
}

void Dialog::on_pushButton_clicked()
{
    QListWidgetItem *pCurrItem = MyListWidget->currentItem();
    if(pCurrItem && pCurrItem->isSelected())
    {
        pCurrItem->setText("YOU");
        QString my_text= pCurrItem->text();
        qDebug()<<my_text;

        pCurrItem->setBackgroundColor(Qt::green);
    }   
}

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