Learning experiments

[learningexperiments-blog]

jQuery

At the moment I’m doing an attendance app, which was given to me and try to simplify by applying the MVO model. 

Realized I didn’t fully understand jQuery so took a detour and went through some classes. A few things made it much clearer for me. 

E.g. $ is abbreviation for jQuery, jQuery is just a function and object. I understood much better children, parent and siblings of the DOM. E.g. 

If I have the below HTML 

<ul>

<li></li>

</ul>

<ul> is the parent to <li>

[learningexperiments-blog]

Project 4: getElementsById

I think I’m finally making some progress in this project. So from what I have understood querySelectorAll() is slower than e.g. getElementsByTagName(). The biggest difference from what I have understood is that querySelectorAll() is a static node list and getElementsByTagName() is live node list.  A live node list is faster because it doesn’t need to have all the information upfront, whereas a static node list needs it. Thanks for this post to pointing it out. 

[learningexperiments-blog]

Thinking of giving up

I have completed the videos for project 4 at Udacity and started the project. I feel totally lost, and thinking of giving up. 

Maybe programming it’s not for me. I don’t seem to have grasped the concepts from the videos and don’t know where to start. 

It’s frustrating to always get stuck and ask for help, and I have to come up with a better study plan for the next project. If I will ever start the next project.  

[learningexperiments-blog]

Started with project 3

I haven't updated in a while, because I have been focusing on other things and have forgot to do it. 

Anyway I have gone through all the videos in Object Oriented Javascript and HTML5 and started with the project. 

We are suppose to do the game frogger and we have been given some code. Just went through the code and comments and realized I'm stuck, I have no idea where to start. I think I have reached this place where I will give up coding for now or find away to break through. 

[learningexperiments-blog]

Pseudoclassical Subclasses

This chapter was a tough one for me, I noticed from the quizzes that I don't understand it yet. 

Today I went through Subclass prototype delegation and how Object.create() method should be used inorder to create a relationship between two classes e.g. if you have a superclass Car and you want your class Van to inherit code from the superclass then you need to setup a relationship between them, this can be done by letting the Van.prototype delegate to the Car.prototype. 

This should be done with Object.create i.e. 

Van.prototype = Object.create(Car.prototype); .

A common way to do it is to use 

Van.prototype = new Car();

But it causes a few problems e.g. every time a new subclass like Van is created, the superclass Car will be invoked which may require an argument which it doesn't have. 

[learningexperiments-blog]

Superclass and subclass

Went through the videos about superclass, and as I understood it is helpful when you are e.g. creating objects which share similarities but have some differences as well. Then you can use a superclass which create the similar attributes for the objects. E.g. if you want to create two different types of cars they might differ in horsepower but they still have similar attributes. Then you  can use a superclass which the two different objects reference to. 

[learningexperiments-blog]

Pseudoclassical Patterns

Today I learned about pseudoclassical patterns, it is called pseudo class since it tries to resemble classes in other languages e.g. PHP or Java.

As I understood it the pseudoclassical patterns make it possible to refactor out code which appear several times in different classes, so you don't have to repeat yourself. 

This can be done by using the keyword new in front of a function invocation i.e. the function is being called upon  e.g. var red = new Car() . 

The function will then be run in a special mode which is called constructor mode. In that mode the interpreter will insert code temporarily that it knows that you need whenever you instancing a new object. 

The purpose is so you don't need to type some of the code. 

[learningexperiments-blog]

Update functional classes

Since I didn't remember what a class was I watched the class again. 

If I have understood it correctly a class build the object that it is going to augment. So basically it is a construct which can create a bunch of objects .

Classes should be written with a capital letter. 

The objects that are created from the construct are called instances of the class. When we call a construct inorder to create an instance that process is called instantiation. 

[learningexperiments-blog]

Functional classes

Today I went through functional classes in javascript and usually I do these reflections right after I have done the class of 25 minutes but today I didn't. So I noticed that now I actually remember that much from class. 

So I guess I have to redo this class tomorrow:)

[learningexperiments-blog]

Object decorator pattorn: Refactoring

Today I learned about refactoring and how I should factor out similar code so I won't need to repeat myself and if I want to do changes to a lot of similar objects I can do changes in one place and not for all the objects separately. 

E.g. if I have some code that creates cars, each car(object) have similarities for example move, stop etc. These similarities should be factored out so I don't have to type the same code for each car object.  

[learningexperiments-blog]

The object prototype

Today I learned about object prototype, however I can't really explain it so I guess I don't understand it either. 

But I believe object prototype is like the object mother to all objects, so anytime you create a object, you have access to all basic methods from the object mother. 

So if you execute some code and your object a doesn't have a property it will go to the object mother instead and look it up. 

[learningexperiments-blog]

Prototype chains

In the beginning of October I started Udacity's frontend nanodegree program. I have finnished three classes and two projects. I'm now on my third project working through the Object-Oriented Javascript class. 

In this session I learned some more about this keyword, I feel I still don't fully understand what it means and why it even exist. However, I manage to understand what the this keyword is being bound to. 

I also learned about prototype chains in javascript, and how an object can copy the properties from one object from another. Either by doing only one time property i.e. when the code is being executed it will only copy the existing properties from e.g. object a to object b. If a property is added to the object a and the code is ran again it will the property which was added will not be copied to object b. 

If you want to that to happen you can instead use object a as a fallback property from object b , by using the Object.create() function i.e. var b = Object.create(a); . If a property is not found in object b the program will look for it in object a instead.  That's how I understood todays 20 min learning. 

[learningexperiments-blog]

Äggröra- starten på äventyret

Torsdagen 9 oktober 2014 var vi hos Marcus för att sätta igång vårt äventyr med att lära oss att laga mat.

Första rätten blev äggröra något som både jag och Markus har lagat flera gånger.  Trots det så lärde vi oss en hel del.

Vi lärde oss b la att mat ska vara rumstempererad för att alla delar ska få en jämn stekyta.

Ett bra sätt att bevara citron är att skära den till mitten och pressa ut saften och sedan spara resten av citronen som den är i kylskåpet.

Det är äggulorna som gör äggröran krämig  så för en schyst krämig 2:1 dvs dubbelt så många äggulor.

Nästa rätt som vi ska laga är Osso Buko.