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Any One Need Help In SDD ? (1 Viewer)
- Thread starter Ace-Pilot
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Dario
Member
What ever happened to Sam Davis ?
Dario
Member
Haha, yes, it is just that there was a big lull between your postings and we thought you had abandoned us. So, are you writing you IT and IPT textbooks at the moment ? What stages of publication are they at ?
Starting to work on the IPT prelim book. I think you may well be married with children by the time the HSC IPT book comes out, it seems a long way off. I think the Pre IPT will be out term 2 2003 and the HSC IPT book at the end of 2003.
Visual Basic can be both ...
Object orientated is where user can control the program with the use of objects such as active X controls...
and event driven, is programs such as drivers which responds to events such as a mouse driver ...
CORRECT ME IF I'M WRONG ...
Object orientated is where user can control the program with the use of objects such as active X controls...
and event driven, is programs such as drivers which responds to events such as a mouse driver ...
CORRECT ME IF I'M WRONG ...
sunny
meh.
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- HSC
- 2002
In an object oriented program, all aspects of the program are represented as individual entities: an object. Objects interact to form the program and solve the problem.
For example, and instance of the 'car' class might be the 'Honda CR-V' object. This object might have properties like 'paint colour' and 'number of seats'. It will also have methods (actions it can perform) like 'go forward' and 'stop'.
An instance of the 'human' class might be the 'driver' object. This object would have methods like 'step on pedal', and properties like 'hair colour' and 'height' (properties of a person).
To make the car go forward, the 'driver' object needs to interact with the 'Honda CR-V' object. You would have to invoke the 'step on pedal' method, which would call the 'Honda CR-V' objects 'go forward' method. Here the 'driver' object has interacted with the 'Honda CR-V' object to achieve a goal.
To be event driven is almost in all modern languages. I think this is more like a feature of a language, rather than a paradigm. Java is a OO language, but you can still use events (but these events are declared as objects as well).
VB strictly is not an OO language. But it depends on how you use it. When you place a command button on your form you are actually placing an instance of the CommandButton class onto your form. This is not commonly known or even important. You can use VB without even knowing you are using an object. In Java however you have to understand the OO paradigm before you can use it since everything in it has to be an object. In VB you can still program your own objects by using class modules, but even then VB is still not a true OO language.
But if you are talking about using a OO or event driven program, it'll appear to be the same!
Hope it helps
For example, and instance of the 'car' class might be the 'Honda CR-V' object. This object might have properties like 'paint colour' and 'number of seats'. It will also have methods (actions it can perform) like 'go forward' and 'stop'.
An instance of the 'human' class might be the 'driver' object. This object would have methods like 'step on pedal', and properties like 'hair colour' and 'height' (properties of a person).
To make the car go forward, the 'driver' object needs to interact with the 'Honda CR-V' object. You would have to invoke the 'step on pedal' method, which would call the 'Honda CR-V' objects 'go forward' method. Here the 'driver' object has interacted with the 'Honda CR-V' object to achieve a goal.
To be event driven is almost in all modern languages. I think this is more like a feature of a language, rather than a paradigm. Java is a OO language, but you can still use events (but these events are declared as objects as well).
VB strictly is not an OO language. But it depends on how you use it. When you place a command button on your form you are actually placing an instance of the CommandButton class onto your form. This is not commonly known or even important. You can use VB without even knowing you are using an object. In Java however you have to understand the OO paradigm before you can use it since everything in it has to be an object. In VB you can still program your own objects by using class modules, but even then VB is still not a true OO language.
But if you are talking about using a OO or event driven program, it'll appear to be the same!
Hope it helps
Event driven and object oriented are quite different things. Its a bit like comparing apples with say walking.
Event driven means that code is executed in response to some event occurring. For example clicking a button, moving over a form, etc.. VB is certainly an event driven language. This has nothing to do with OO.
In VB, controls have both properties and events, so in a sense these controls seems to be like OO objects, but they are not. In OO you can't change the data (attributes) of an object from outside the object, only the objects methods can alter the data within the object. This means the object (or instance of the object) has total control over its data. In other words the interface between objects is solely via their methods. This is not the case with VB controls, we can alter their properties at will.
You need to read more about this if you're doing the first option Evolution of Programming Languages, its not easy to describe OO in a single paragraph.
Event driven means that code is executed in response to some event occurring. For example clicking a button, moving over a form, etc.. VB is certainly an event driven language. This has nothing to do with OO.
In VB, controls have both properties and events, so in a sense these controls seems to be like OO objects, but they are not. In OO you can't change the data (attributes) of an object from outside the object, only the objects methods can alter the data within the object. This means the object (or instance of the object) has total control over its data. In other words the interface between objects is solely via their methods. This is not the case with VB controls, we can alter their properties at will.
You need to read more about this if you're doing the first option Evolution of Programming Languages, its not easy to describe OO in a single paragraph.
Hey SamD~!
My school is using your HSC SDD book and I was just wondering how long did it take u guys 2 chuck it together??
The content seems ok, but some of the questions & multiple choice q's are a shocker (Sorry Sam).
I s'pose this isn't really a question specific to the software course but, why isn't it possible for a group of teachers / academics to sit down and right one text book which is the pescribed text for all HSC students sitting for the course?
Hope you can add to my pool of useless knowledge
My school is using your HSC SDD book and I was just wondering how long did it take u guys 2 chuck it together??
The content seems ok, but some of the questions & multiple choice q's are a shocker (Sorry Sam).
I s'pose this isn't really a question specific to the software course but, why isn't it possible for a group of teachers / academics to sit down and right one text book which is the pescribed text for all HSC students sitting for the course?
Hope you can add to my pool of useless knowledge
No sure what you mean in regard to the questions?
We've tried to model the questions on those that could be expected in the HSC. This means that often they are somewhat open ended, that is, apart from the Multi choice there is often no one correct answer.
In the first print of the text there were a few misprints, which have been corrected in subsequent reprints.
We've tried to model the questions on those that could be expected in the HSC. This means that often they are somewhat open ended, that is, apart from the Multi choice there is often no one correct answer.
In the first print of the text there were a few misprints, which have been corrected in subsequent reprints.
iptteacherssuck
Member
- Joined
- Aug 10, 2002
- Messages
- 193
seriously..the textbook authors hav eno idea what OOP is. well not u sam davis but other authors...
Firstly,
Object is an instance of class.
So
Class could be "Human"
then an instance of that class, hence Human object could be "Tim"
The object tim has all the characteristic of Human, as it IS a Human class.
Sunny's eg of Driver is quiet misleading IMO.
That is more of inheritance concept.
What you can do is, u make a new class "base on" a different class. So you can make a class called driver based on the class Human. this makes sense cuz All drivers are human. But not all human are drivers.
You can then add methods and properties that are unique t each new classes such as method drive() for driver and cook() for cook. BUT THEY WILL ALL Have methods and properties of Human class. EG, eat(), sleep() etc
There can be many different class with one base. So, driver, cook, iptteachers/morons, sddteachers/less morons, chemteachers etc
Now that called inheritance.inheritting a class to make a new class
Now... Polymorphism.
When you program using objects..there are times when u wanna treat drivers, cook etc as on tpye.reason could be that u wanna make a collection of humans. Then what u can do is treat, driver
as a human class/object. althuogh u loose all the unique methos and properties of the class but u can treat them all like human and its easier to handle the data..and programming becomes simple. you really need to try this in ur own program to see its benefit..
did this help?
Concept of events are something that have been built using the OOP languages. It is nothing more than an array of commands.
When an event is some how invoked, it runs thru that list of commands.
Events are really invoked like a fuction, and is invoked within the objects so you won't know exactly how it is invoked or when it is invoked other than from its name, eg. "OnSleep()". u can probably guess that the event is called when Sleep() method is executed.
When you have an event handler, you are registering commands to that array of commands i spoke abut b4.
So technically u can have 50 event handlers for one event. And u can do this with c# and other oop languages.
VB is not an oop cuz it does'nt have
polymorphism,inheritance.
well not u sam davis but other authors...Firstly,
Object is an instance of class.
So
Class could be "Human"
then an instance of that class, hence Human object could be "Tim"
The object tim has all the characteristic of Human, as it IS a Human class.
Sunny's eg of Driver is quiet misleading IMO.
That is more of inheritance concept.
What you can do is, u make a new class "base on" a different class. So you can make a class called driver based on the class Human. this makes sense cuz All drivers are human. But not all human are drivers.
You can then add methods and properties that are unique t each new classes such as method drive() for driver and cook() for cook. BUT THEY WILL ALL Have methods and properties of Human class. EG, eat(), sleep() etc
There can be many different class with one base. So, driver, cook, iptteachers/morons, sddteachers/less morons, chemteachers etc
Now that called inheritance.inheritting a class to make a new class
Now... Polymorphism.
When you program using objects..there are times when u wanna treat drivers, cook etc as on tpye.reason could be that u wanna make a collection of humans. Then what u can do is treat, driver
as a human class/object. althuogh u loose all the unique methos and properties of the class but u can treat them all like human and its easier to handle the data..and programming becomes simple. you really need to try this in ur own program to see its benefit..
did this help?
Concept of events are something that have been built using the OOP languages. It is nothing more than an array of commands.
When an event is some how invoked, it runs thru that list of commands.
Events are really invoked like a fuction, and is invoked within the objects so you won't know exactly how it is invoked or when it is invoked other than from its name, eg. "OnSleep()". u can probably guess that the event is called when Sleep() method is executed.
When you have an event handler, you are registering commands to that array of commands i spoke abut b4.
So technically u can have 50 event handlers for one event. And u can do this with c# and other oop languages.
VB is not an oop cuz it does'nt have
polymorphism,inheritance.
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I've written a teacher resource kit that contains fully worked answers to all the questions in my text. It also has heaps of other stuff, such as explanations for each of the group tasks, a CD with sample code and demo software, etc... its about 200+ pages long, it sells for about $95.
If you want answers to a specific question in the text, just ask me and I'll reply!
If you want answers to a specific question in the text, just ask me and I'll reply!
Hey Sam~!
i went through your textbook comparing it 2 the syllabus and looks like u 've missed out a couple of points...
In software developers view of hardware i was alright with the points
* Generating outputs to an appropriate output device &
* Specialist devides
not being there clearly outlined like the other points of the syllabus (coz it's fairly self explanitory), but what exactly comes under the point of
* Printer operation? (hardware option topic again)
there is another point from the syllabus that i wasn't too sure about, but can't find it written in my book at the moment! nothing major though~!
Would b great if u could give us a yell b4 our exam
Thanks heaps!
i went through your textbook comparing it 2 the syllabus and looks like u 've missed out a couple of points...
In software developers view of hardware i was alright with the points
* Generating outputs to an appropriate output device &
* Specialist devides
not being there clearly outlined like the other points of the syllabus (coz it's fairly self explanitory), but what exactly comes under the point of
* Printer operation? (hardware option topic again)
there is another point from the syllabus that i wasn't too sure about, but can't find it written in my book at the moment! nothing major though~!
Would b great if u could give us a yell b4 our exam
Thanks heaps!
Actually all that stuff is dealt with in Set 10F Questions 11-15.
When writing the book it seemed very repetitious to go over essentially the same theory for first input then output then printers and then specialist devices, rather I've tried to combine them all. The point is to understand and interpret the effects of the data stream, the type of device being relatively insignificant. I used a mouse and a PABX, however I could equally have used a monitor and some sort of robot.
As printers are, for some unknown reason, explicitly mentioned in the syllabus I've made sure to include questions on this, namely 10F Q13-15.
If you want my suggested answers from the Teacher Resource Kit for these questions then let me know.
When writing the book it seemed very repetitious to go over essentially the same theory for first input then output then printers and then specialist devices, rather I've tried to combine them all. The point is to understand and interpret the effects of the data stream, the type of device being relatively insignificant. I used a mouse and a PABX, however I could equally have used a monitor and some sort of robot.
As printers are, for some unknown reason, explicitly mentioned in the syllabus I've made sure to include questions on this, namely 10F Q13-15.
If you want my suggested answers from the Teacher Resource Kit for these questions then let me know.