view/item

[goldhappywang]

Hi,
I have a problem , I want to the view(like QGraphicsView) zoom in ,at the same time the items can't change,
some one tell me rewrite the paint() ,but I don't know how to do it? I seek to a share of code about the View/Items .
Thanks a lot!

[wysota]

I'm not sure I understand what you want, but assuming you want to zoom the view without zooming the items in it, you want to set QGraphicsItem::ItemIgnoresTransformations flag on each of the items.

[goldhappywang]

I have rewrite new view and items, they are't QGraphicsView and QGrphicsItem
But in the new Frame, I want to zoom the view without zooming the items in it

[wysota]

What's the problem then?

[goldhappywang]

it show blank space in the drawtext() ,in the first it show a QString, and it also scale when the view scale.
the code
begin:

void QzCanvasTagItem::paint(QPainter * painter)
{
      drawText(Rect(), Qt::AlignLeft,_text);
}

void QzCanvasTagItem::paint(QPainter * painter)
{
      drawText(Rect(), Qt::AlignLeft,_text);
}

To copy to clipboard, switch view to plain text mode 

it show a rect with text

after:

void QzCanvasTagItem::paint(QPainter * painter,QWidget *widget)
{
    painter->save();
   QWidget *w;
    w = widget->parentWidget();
 
   QzCanvasView *v;
   v = (QzCanvasView *)w;
    //In there, I don't konw what to do 
   drawText(Rect(), Qt::AlignLeft,_text);
   painter->restore();
}

void QzCanvasTagItem::paint(QPainter * painter,QWidget *widget)
{
    painter->save();
   QWidget *w;
    w = widget->parentWidget();
    
   QzCanvasView *v;
   v = (QzCanvasView *)w;
    //In there, I don't konw what to do 
   drawText(Rect(), Qt::AlignLeft,_text);
   painter->restore();
}

To copy to clipboard, switch view to plain text mode 

it show blank space ,the text disapper
and the Item also scale with view scale

[wysota]

And how is that related to zooming? What is QzCanvasTagItem? What drawText()? What is this code supposed to do?

[goldhappywang]

the QzCanvasTagItem is similar to QGraphicsItem,
QzcanvasView is similar to QGraphicsView
the zoom is similar to scale
but they don't inherit from QGraphicsView and QGraphicsItem,
drawText () ------show a rect with text but the rect don't change with the view scale

[wysota]

What does "similar" mean in this context? How do you use those classes?

Please use [code] tags in your posts.

[goldhappywang]

they are inherit from class Canvas , the QGraphicesView replace the Canvas, I want to achieve the same effect as some function in QGraphiceItem ,
I push a QPushButton the view zoom in or zoom out , but I want the Items on the view the don't zoom

[wysota]

As for now I have seen not a single line of code related to zooming.

[goldhappywang]

yes, zoom in the view ,I have finished it ,It can run,
now I want to ask for help about item,
a list of item on the view ,
for example : QGraphicsView::scale(); one item on the QGraphicsView also scale(),
I want to "QGraphicsView::scale(); one item on the QGraphicsView not scale()"
it don't related to view ,only what to do with item
do you understand?

[wysota]

No, I don't understand

[goldhappywang]

oh,my god!

[faldzip]

I'm also trying hard to understand but I failed with that... :P maybe draw your problem in ms paint or something cause your explanation is a bit messy...

[wysota]

I'm also trying hard to understand but I failed with that... :P maybe draw your problem in ms paint or something cause your explanation is a bit messy...

It would be enough to use full sentences with simple English terms and simple grammar. Expressing full ideas instead of expecting one to guess them helps as well.

[goldhappywang]

I'm sorry for the explanation .
a QGraphicisView object and a QGraphicsItem on the object ,
if QGraphicsView object scale
but the QGraphicsItem does't scale,
what to do it

[wysota]

I already told you at the very beginning - set ItemIgnoresTransformations flag on each of the items.