Interactive text formatting in QGraphicsTextItem

[olelukoie]

I've got a problem with interactive text formatting inside a QGraphicsTextItem (more correctly inside my own QGraphicsTextItem-derived class).

I have created the same toolbar as in diagramscene example with five controls - two combos and three buttons - and implemented my own text formatting methods using QTextCursor to apply new formatting to selected text fragments only.

The problem is that when I click on the toolbar on font or font size combo the item on the scene looses focus (and thus looses text selection) and formatting doesn't applies to the text. At the same time simple buttons (bold, italic etc) work OK. It seems that I've missed some option that prevents item from loosing its focus when the mouse pointer leaves the scene or something like this.

Can anybody help me to solve this? Thanks in advance.

PS. I've looked at textedit demo and found that it connects combos' activated() signals to custom slots. It this a solution to this problem? Is there a more advanced example (than the buggy diagramscene) on how to interactively format text inside QGraphicsTextItem?

[wysota]

Try setting focus policy of those troublesome widgets to NoFocus.

[olelukoie]

Try setting focus policy of those troublesome widgets to NoFocus.

You mean combo boxes? I've already tried this and found that then I loose the "editable" ability for them (combo box still allows me to select its current value with a mouse but keyboard input doesn't work). It's not critical for font selection but very important for font size combo box.

[wysota]

I don't know how you would expect it to work then... You either have focus in one item or the other, not in both at once... What you can do is to remember the previously focused item so that you know what to apply the formatting on.

[olelukoie]

I don't know how you would expect it to work then... You either have focus in one item or the other, not in both at once...

I have created a couple of screenshots that demonstrate the behavior I need. The first one is an MS Visio diagram and the second one is an OOo Draw diagram.

As you can see on these shots the text cursor (caret) is in font size combo box and it is possible to edit its value with keyboard while the shape on the "scene" remains visually active, selected and seems doesn't loose focus so the text selection is not cleared and displayed using "active" colors.

[wysota]

"Visually active" means "selected". Selection and focus are two different things. Multiple things can be selected but only one can have keyboard focus.

[olelukoie]

"Visually active" means "selected". Selection and focus are two different things. Multiple things can be selected but only one can have keyboard focus.

Mmm, well, I see... Do you mean that an item can be selected and not have focus at the same time? What should I do to achieve this? How to keep an item selected when focus leaves the scene? By default QGraphicsTextItem becomes inactive when I select combo box on the toolbar. Diagramscene demo doesn't show this ability. Furthermore, in this demo the text item exits text editing mode when it looses focus thus loosing the text selection. I've tried to override focus in and focus out event handlers of the item but it didn't help. Should I reimplement some scene events (currently I only reimplement some items' and view's events and use the standard scene)? Can you point me to the working example?

[wysota]

Mmm, well, I see... Do you mean that an item can be selected and not have focus at the same time? What should I do to achieve this?

Nothing. Selection and focus are two separate mechanisms controled by two different flags.

By default QGraphicsTextItem becomes inactive when I select combo box on the toolbar.

Because it loses focus and was never selected. If you select it, it will stay that way until you deselect it.

Diagramscene demo doesn't show this ability. Furthermore, in this demo the text item exits text editing mode when it looses focus thus loosing the text selection.

Was it ever selected?

[olelukoie]

Was it ever selected?

Surely yes. Run diagramscene demo, create text item, enter some text, select some portion of this text and click inside the font size combo box. Text selection would be cleared (lost). My question is how to keep it so that formatting changes apply to selected text fragment only and not to the whole text of the item.

[olelukoie]

So can anybody help me or point to a working example?

[wysota]

We still haven't seen a minimal compilable example reproducing the problem