109 lines
2.7 KiB
Clojure
109 lines
2.7 KiB
Clojure
|
|
=== Objectif ===
|
|
:** Understand ewol basic [class[ewol::Object]]
|
|
:** Use [class[ewol::Object]] correctly
|
|
|
|
== Basis of the ewol::Object ==
|
|
|
|
An object in Ewol is a simple class : [class[ewol::Object]] This object is the basis of all element in the ewol system.
|
|
This is designed to manage many common things:
|
|
|
|
:** Unique ID
|
|
:** Name
|
|
:** Parameters
|
|
:** Signal generation
|
|
:** Xml configuration
|
|
:** Removing
|
|
:** Perodic calling
|
|
|
|
[note]
|
|
Please do not compare with the gObject basic class...
|
|
[/note]
|
|
|
|
|
|
== Create an Object: ==
|
|
|
|
Creating an object is really simple:
|
|
|
|
[code style=c++]
|
|
std::shared_ptr<ewol::Button> tmpButon = ewol::Button::create();
|
|
APPL_INFO("We just create a button widget with unique ID=" << tmpButon->getId() << " name='" << tmpButon->getName() << "'");
|
|
[/code]
|
|
|
|
Note that all object created are std::shared_ptr.
|
|
|
|
|
|
Set the name of the object:
|
|
|
|
[code style=c++]
|
|
tmpButon->setName("my widget name");
|
|
APPL_INFO("We just create an Object with ID=" << tmpButon->getId() << " name='" << tmpButon->getName() << "'");
|
|
[/code]
|
|
|
|
|
|
== Remove an Object: ==
|
|
|
|
Simply use the function:
|
|
[code style=c++]
|
|
tmpButon->destroy();
|
|
[/code]
|
|
|
|
This function request his parrent to remove the std::shared_ptr it keep on it.
|
|
And when all std::shared_ptr is removed the object will be really removed.
|
|
|
|
At his point we can think an object is allive all the time someone keep a reference on it, then when you are not a parrent of the object, do not keep a std::shared_ptr but a std::weak_ptr.
|
|
|
|
[note]
|
|
If some Object is not removed when you close the application, the system inform you with displaying all object already alive.
|
|
[/note]
|
|
|
|
|
|
== Retrieve an Object: ==
|
|
|
|
In Ewol this is possible to get a object with his name.
|
|
|
|
=== Find a global Object (ouside an Object) ===
|
|
|
|
[code style=c++]
|
|
#include <ewol/context/Context.h>
|
|
|
|
std::shared_ptr<ewol::Object> tmpObject = ewol::getContext().getEObjectManager().getObjectNamed("obj Name");
|
|
if (tmpObject == NULL) {
|
|
APPL_ERROR("The Object does not exist");
|
|
}
|
|
[/code]
|
|
|
|
=== Find a global Object (inside an Object) ===
|
|
|
|
[code style=c++]
|
|
std::shared_ptr<ewol::Object> tmpObject = getObjectNamed("obj Name");
|
|
if (tmpObject == NULL) {
|
|
APPL_ERROR("The Object does not exist");
|
|
}
|
|
[/code]
|
|
|
|
=== Find a sub-object ===
|
|
|
|
[code style=c++]
|
|
std::shared_ptr<ewol::Object> tmpObject = getSubObjectNamed("obj Name");
|
|
if (tmpObject == NULL) {
|
|
APPL_ERROR("The Object does not exist");
|
|
}
|
|
[/code]
|
|
|
|
=== retriving your object type ===
|
|
|
|
It could be really interesting to retrive your own instance:
|
|
|
|
[code style=c++]
|
|
std::shared_ptr<ewol::Object> tmpObject ...;
|
|
|
|
std::shared_ptr<appl::MyOwnObject> myObject = std::dynamic_pointer_cast<appl::MyOwnObject>(tmpObject);
|
|
[/code]
|
|
|
|
== conclusion ==
|
|
|
|
TODO ...
|
|
|
|
|