How to access ui from another class in qt C++

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Hi,

I have a requirement that I need to access ui from another class. I have to assign a png to a label from that class. For this I have created a function in my widget.cpp to assign the png to the label. And from another class(ApplicationWindow) I have created a widget class object and through that object I am calling widget class function. Here the problem is I am able to access the widget class fucntion but unable to assign the png to label. Can you please provide the solution for this.

What I have tried:

Widget.cpp

void Widget::Display_image()
{
qDebug()<<"In Display function";
QPixmap pixmap("/root/rfid.png");
ui->label_image->setPixmap(pixmap);
ui->label_image->setScaledContents( true );
ui->label_image->setSizePolicy( QSizePolicy::Ignored, QSizePolicy::Ignored );

}

ApplicationWindow.cpp

void ApplicationWindow::closeApp()
{
Widget obj; // from here I need to access ui
obj.Display_image();

}

Here Iam able to print "In Display function" with qDebug but label not displaying image.

Posted 27-Mar-19 19:43pm

Member 13740197

Updated 27-Mar-19 21:35pm

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KarstenK · Accepted Answer · 2019-03-27T21:35:00

Solution 1

You need to access the correct object like a member from the ApplicationWindow. Your Widget is a local object and gets destroyed after leaving the function.

Using some pointers often helps.

Posted 27-Mar-19 21:35pm

KarstenK

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Member 13740197 24-Apr-19 1:43am

Hi
After using pointers also I am unable to access ui. Below is which I have used.

Widget *obj;
obj->Display_image();

also tried below

Widget *obj = new Widget();
obj->Display_image();

Can you please provide me the solution.