ewol/doc/tutorial/011_ObjectConfig.bb
2014-09-09 21:15:50 +02:00

99 lines
2.7 KiB
Clojure

=== Objectif ===
:** Understand ewol::Object configuration parameter
:** Create an configurable object
== Configuration using ==
All [class[ewol::Object]] have a configuration of parameters (the object name is a parameter), Then we need to set get and use xml to update parameters.
=== Set a Parameter ===
[note]
Using getter and setter is really better, and faster.
[/note]
==== With a string configuration ====
[code style=c++]
if (tmpObject->parameterSet("name", "new name of object") == false) {
APPL_ERROR("Can not set object parameter");
}
[/code]
==== whith the object name ====
[code style=c++]
if (parameterSetOnWidgetNamed("objectName", "value", "16.2") == false) {
APPL_ERROR("Can not set object parameter");
}
[/code]
=== Get Parameter ===
[code style=c++]
std::string val = tmpObject->parameterGet("name");
APPL_INFO("Get Object property : name='" << val << "'");
[/code]
== Implement configuration ==
[code style=c++]
#include <ewol/object/Object.h>
namespace appl {
class MyObj : public ewol::Object {
protected:
//! @brief Constructor
MyObj(void) :
m_value(*this, "value", false, "Value of the parameter (descrition string)") {
// nothing to do..
}
void init() {
ewol::Object::init();
}
public:
//! @brief Destructor
virtual ~MyObj(void) { }
DECLARE_FACTORY(MyObj);
private:
ewol::object::Param<bool> m_value; //!< Internal Object value
public:
//! @brief Setter
void setValue(bool _val) {
m_value.set(_val);
}
//! @brief Getter
bool getValue() const {
return m_value.get();
}
public: // herited function:
void onParameterChangeValue(const ewol::object::ParameterRef& _paramPointer) {
if (_paramPointer == m_value) {
APPL_DEBUG("The internal value has change, new value is : '" << m_value.get() << "'");
}
}
}
}
[/code]
In the contructor we need to add:
[code style=c++]
m_value(*this, "value", false, "Value of the parameter (descrition string)")
[/code]
:** [b]'*this':[/b] Reference the main class to call it chen value change.
:** [b]"value":[/b] Is the name of the parameter.
:** [b]false:[/b] The default value.
:** [b]"....."[/b] Description of the parameter (optionnal).
The function [b]onParameterChangeValue[/b] is called only the parameter change (no historic has been registered)
The last point is that the m_value.get() is an inline fuction then it take no more CPU cycle to access the value than normal variable.
Some other parameter are availlable :
:** ewol::object::Param<T> Basic parameter.
:** ewol::object::ParamRange<T> For numeric parameter that range value are check befor setting new value.
:** ewol::object::ParamList<T> For List of parameter values.