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Qt's meta-object system provides the signals and slots mechanism for inter-object communication, run-time type information, and the dynamic property system. The meta-object system is based on three things: • The class provides a base class for objects that can take advantage of the meta-object system. • The macro inside the private section of the class declaration is used to enable meta-object features, such as dynamic properties, signals, and slots. • The ( moc) supplies each subclass with the necessary code to implement meta-object features. The moc tool reads a C++ source file. If it finds one or more class declarations that contain the macro, it produces another C++ source file which contains the meta-object code for each of those classes.
This generated source file is either #include'd into the class's source file or, more usually, compiled and linked with the class's implementation. In addition to providing the mechanism for communication between objects (the main reason for introducing the system), the meta-object code provides the following additional features: • () returns the associated for the class.
The Meta-Object Compiler, moc, is the program that handles Qt's C++ extensions. The moc tool reads a C++ header file. If it finds one or more class declarations that contain the Q_OBJECT macro, it produces a C++ source file containing the meta-object code for those classes.
• () returns the class name as a string at run-time, without requiring native run-time type information (RTTI) support through the C++ compiler. • () function returns whether an object is an instance of a class that inherits a specified class within the inheritance tree. • () and () translate strings for.
• () and () dynamically set and get properties by name. • () constructs a new instance of the class. It is also possible to perform dynamic casts using () on classes.
The () function behaves similarly to the standard C++ dynamic_cast(), with the advantages that it doesn't require RTTI support and it works across dynamic library boundaries. Contoh program sederhana kondisi pada cobol 2017. It attempts to cast its argument to the pointer type specified in angle-brackets, returning a non-zero pointer if the object is of the correct type (determined at run-time), or 0 if the object's type is incompatible. For example, let's assume MyWidget inherits from and is declared with the macro.
Templates are a builtin mechanism in C++ that allows the compiler to generate code on the fly, depending on the type of the arguments passed. As such, templates are highly interesting to framework creators, and we do use advanced templates in many places in Qt. However, there are limitations: There are things that you can easily express with templates, and there are things that are impossible to express with templates. A generic vector container class is easily expressible, even with partial specialisation for pointer types, while a function that sets up a graphical user interface based on an XML description given as a string is not expressible as a template. And then there is a gray area in between. Things that you can hack with templates at the cost of code size, readability, portability, usability, extensability, robustness and ultimately design beauty. Both templates and the C preprocessor can be stretched to do incredibility smart and mind boggling things.
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Qt\'s meta-object system provides the signals and slots mechanism for inter-object communication, run-time type information, and the dynamic property system. The meta-object system is based on three things: • The class provides a base class for objects that can take advantage of the meta-object system. • The macro inside the private section of the class declaration is used to enable meta-object features, such as dynamic properties, signals, and slots. • The ( moc) supplies each subclass with the necessary code to implement meta-object features. The moc tool reads a C++ source file. If it finds one or more class declarations that contain the macro, it produces another C++ source file which contains the meta-object code for each of those classes.
This generated source file is either #include\'d into the class\'s source file or, more usually, compiled and linked with the class\'s implementation. In addition to providing the mechanism for communication between objects (the main reason for introducing the system), the meta-object code provides the following additional features: • () returns the associated for the class.
The Meta-Object Compiler, moc, is the program that handles Qt\'s C++ extensions. The moc tool reads a C++ header file. If it finds one or more class declarations that contain the Q_OBJECT macro, it produces a C++ source file containing the meta-object code for those classes.
• () returns the class name as a string at run-time, without requiring native run-time type information (RTTI) support through the C++ compiler. • () function returns whether an object is an instance of a class that inherits a specified class within the inheritance tree. • () and () translate strings for.
• () and () dynamically set and get properties by name. • () constructs a new instance of the class. It is also possible to perform dynamic casts using () on classes.
The () function behaves similarly to the standard C++ dynamic_cast(), with the advantages that it doesn\'t require RTTI support and it works across dynamic library boundaries. Contoh program sederhana kondisi pada cobol 2017. It attempts to cast its argument to the pointer type specified in angle-brackets, returning a non-zero pointer if the object is of the correct type (determined at run-time), or 0 if the object\'s type is incompatible. For example, let\'s assume MyWidget inherits from and is declared with the macro.
Templates are a builtin mechanism in C++ that allows the compiler to generate code on the fly, depending on the type of the arguments passed. As such, templates are highly interesting to framework creators, and we do use advanced templates in many places in Qt. However, there are limitations: There are things that you can easily express with templates, and there are things that are impossible to express with templates. A generic vector container class is easily expressible, even with partial specialisation for pointer types, while a function that sets up a graphical user interface based on an XML description given as a string is not expressible as a template. And then there is a gray area in between. Things that you can hack with templates at the cost of code size, readability, portability, usability, extensability, robustness and ultimately design beauty. Both templates and the C preprocessor can be stretched to do incredibility smart and mind boggling things.
...'>Qt Meta Object Compiler Installation(01.09.2018)Qt\'s meta-object system provides the signals and slots mechanism for inter-object communication, run-time type information, and the dynamic property system. The meta-object system is based on three things: • The class provides a base class for objects that can take advantage of the meta-object system. • The macro inside the private section of the class declaration is used to enable meta-object features, such as dynamic properties, signals, and slots. • The ( moc) supplies each subclass with the necessary code to implement meta-object features. The moc tool reads a C++ source file. If it finds one or more class declarations that contain the macro, it produces another C++ source file which contains the meta-object code for each of those classes.
This generated source file is either #include\'d into the class\'s source file or, more usually, compiled and linked with the class\'s implementation. In addition to providing the mechanism for communication between objects (the main reason for introducing the system), the meta-object code provides the following additional features: • () returns the associated for the class.
The Meta-Object Compiler, moc, is the program that handles Qt\'s C++ extensions. The moc tool reads a C++ header file. If it finds one or more class declarations that contain the Q_OBJECT macro, it produces a C++ source file containing the meta-object code for those classes.
• () returns the class name as a string at run-time, without requiring native run-time type information (RTTI) support through the C++ compiler. • () function returns whether an object is an instance of a class that inherits a specified class within the inheritance tree. • () and () translate strings for.
• () and () dynamically set and get properties by name. • () constructs a new instance of the class. It is also possible to perform dynamic casts using () on classes.
The () function behaves similarly to the standard C++ dynamic_cast(), with the advantages that it doesn\'t require RTTI support and it works across dynamic library boundaries. Contoh program sederhana kondisi pada cobol 2017. It attempts to cast its argument to the pointer type specified in angle-brackets, returning a non-zero pointer if the object is of the correct type (determined at run-time), or 0 if the object\'s type is incompatible. For example, let\'s assume MyWidget inherits from and is declared with the macro.
Templates are a builtin mechanism in C++ that allows the compiler to generate code on the fly, depending on the type of the arguments passed. As such, templates are highly interesting to framework creators, and we do use advanced templates in many places in Qt. However, there are limitations: There are things that you can easily express with templates, and there are things that are impossible to express with templates. A generic vector container class is easily expressible, even with partial specialisation for pointer types, while a function that sets up a graphical user interface based on an XML description given as a string is not expressible as a template. And then there is a gray area in between. Things that you can hack with templates at the cost of code size, readability, portability, usability, extensability, robustness and ultimately design beauty. Both templates and the C preprocessor can be stretched to do incredibility smart and mind boggling things.
...'>Qt Meta Object Compiler Installation(01.09.2018)