element::click

[Xeverous]

This is a bit werid to me:

All element event reaction functions return bool to indicate whether the event was handled or ignored, except 2:

• drag returns void
• click returns element*

For the first, is there any motivation behind it? Why not inform parent elements of dragging acceptance?

For the second - isn't this redundant due to element* hit_test(context const&, point)? The are very few uses of the return value and currently all of them are either null pointer checks or forwards to the caller just because the function returns something. This means that the interface could be reduced to return bool with no impact on implementation.

lib/include/elements/element/button.hpp:256:      auto r = basic_latching_button<Base>::click(ctx, btn);
                                        257-      this->do_click(ctx, this->value(), was_selected);
                                        258-      return r;                             // forward
lib/include/elements/element/indirect.hpp:190:      return this->get().click(ctx, btn); // forward
lib/src/element/composite.cpp:70:               if (info.element->click(ectx, btn))     // used as bool
lib/src/element/composite.cpp:83:            if (e.click(ectx, btn))                    // used as bool
lib/src/element/popup.cpp:60:      auto r = floating_element::click(new_ctx, btn);
                          61-      if (btn.down && ((r == nullptr) || hit))             // used as bool
lib/src/element/port.cpp:318:      return port_element::click(ctx, btn);                // forward
lib/src/element/proxy.cpp:82:      auto r = subject().click(sctx, btn);
                          83-      restore_subject(sctx);
                          84-      return r;                                            // forward

[djowel]

Good point, actually. I will analyze and think about it some more. Added in the TODO list: #216

[djowel]

Implemented and pushed in develop.

6bc02ca

[djowel]

For the first, is there any motivation behind it? Why not inform parent elements of dragging acceptance?

Ah I missed your first item. Next time, please, one issue at a time. Anyway, it is of no consequence. There is no need to inform the parent elements of dragging acceptance. If you have a use-case for it, I'd like to know more.

[Xeverous]

If you have a use-case for it, I'd like to know more.

Generally, I would refrain from blocking information from child elements. This is a different topic, but composites do not forward some events if the child is outside click bounds - what if I want to make an element that reacts to mouse/keys regardless of its position?