CODEWITHSUNDEEP
c++linuxqtrosqvtkwidget
miaa
miaa

Reputation: 21

Issue with QVTKWidget in Qt Ros workspace

I am new to Qt and ROS. I am working on Qt Creator 4.8.0. I have created a catkin workspace in Qt and a mainwindow was created. And I am trying to add QVTKWidget to the mainwindow. It was successfully built but when it is run, an error message is displayed.

Code: mainwindow.cpp

vtkWidget = new QVTKWidget;
ui.verticalLayout->addWidget(vtkWidget);
ui.verticalLayout->update();
ren = vtkRenderer::New();
vtkWidget->GetRenderWindow()->AddRenderer(ren);
ren->SetBackground(1.0,0,0);
ren->Render();

Error:realloc(): invalid pointer: 0x00007facb5723820 ***
======= Backtrace: =========
/lib/x86_64-linux-gnu/libc.so.6(+0x777e5)[0x7facb37d77e5]
/lib/x86_64-linux-gnu/libc.so.6(+0x85d80)[0x7facb37e5d80]
/lib/x86_64-linux-gnu/libc.so.6(realloc+0x22f)[0x7facb37e48ef]
/usr/lib/x86_64-linux-gnu/libQt5Core.so.5(_ZN9QListData7reallocEi+0x1f)[0x7facada009cf]
/usr/lib/x86_64-linux-gnu/libQt5Core.so.5(_ZN9QListData6appendEi+0x81)[0x7facada00aa1]
/usr/lib/x86_64-linux-gnu/libQt5Core.so.5(+0x1d6d78)[0x7facadaccd78]
/usr/lib/x86_64-linux-gnu/libQt5Core.so.5(_Z21qRegisterResourceDataiPKhS0_S0_+0x2e6)[0x7facadac8b16]
/usr/lib/x86_64-linux-gnu/libQt5Core.so.5(+0x7bcc3)[0x7facad971cc3]
/lib64/ld-linux-x86-64.so.2(+0x106ba)[0x7facb6c5a6ba]
/lib64/ld-linux-x86-64.so.2(+0x107cb)[0x7facb6c5a7cb]
/lib64/ld-linux-x86-64.so.2(+0xc6a)[0x7facb6c4ac6a]

Upvotes: 1

Views: 80

Answers (1)

p-a-o-l-o
p-a-o-l-o

Reputation: 10057

You should check if vtkWidget->GetRenderWindow() returns a valid pointer, before calling AddRenderer on it, so instead of

vtkWidget->GetRenderWindow()->AddRenderer(ren);

try

vtkRenderWindow * window = vtkWidget->GetRenderWindow();
if(window != nullptr)
{
     window->AddRenderer(ren);
     //etc.

Same check should be applied to the vtkRenderer as well:

ren = vtkRenderer::New();
if(ren != nullptr)
{
    //etc.

If you happen to spot some null pointer, see if this post helps.

Upvotes: 1

Related Questions