QTreeView no show inside QDockWidget

[d_stranz]

I put the declaration of QTreeView into the header file, and it works!!!

That's still the wrong way to do it, Qt-wise. You should create the tree view instance on the heap, not the stack:

QTreeView * w = new QTreeView( swatch1 );
w->setModel(&model);
swatch1->setWidget( w );
w->setEnabled(true);

QTreeView * w = new QTreeView( swatch1 );
w->setModel(&model);
swatch1->setWidget( w );
w->setEnabled(true);

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If you need access to the tree widget from outside the methond where you create it, then put the "QTreeView * w;" declaration as a member variable of the class in the header file.