[[TOC]]

= Squeak FAQ - New Version =

== Documentation ==

=== Where do I find good introductory literature for !Squeak/Smalltalk? ===

The book [http://www.squeakbyexample.org/ Squeak by Example] is a good starting point. Especially, the book explains the most important tools, the morphic framework and important concepts, such as messages.

In the [http://wiki.squeak.org/squeak/792#Morphic morphic wiki] you can find tutorials how to work with morphic and squeak.

There are also many books available for free: An overview can be found here: [http://stephane.ducasse.free.fr/FreeBooks.html Stephane Ducasse: Free Books]

We also created some [https://www.hpi.uni-potsdam.de/hirschfeld/trac/SqueakCommunityProjects/wiki/squeak_screencasts screencasts] explaining how to work with squeak.

=== Where do I find a good documentation? ===

For most of the classes you can view the documentation directly in the browser. The "?" Button between class and instance shows class comments.

Furthermore, we recommend the following websites: 

* [http://squeakbyexample.org/ Squeak by Example]

* [http://static.squeak.org/tutorials/morphic-tutorial-1.html Morphic Tutorial]

* [http://wiki.squeak.org/squeak/30 Squeak-Wiki]

* [https://www.hpi.uni-potsdam.de/hirschfeld/trac/SqueakCommunityProjects/wiki/squeak_screencasts Squeak Screencasts]

* [http://wiki.squeak.org/squeak/5699 Terse guide to Squeak]

== Smalltalk Syntax ==

=== How do I leave a method without returning a value, e.g. early return? ===
In Smalltalk `^` behaves similar to return in other languages. If a method in Smalltalk should return nothing, typically you return `self`. You should avoid to return `nil`.

=== How do I break inside a loop? ===
A way to do so is to put the loop into its own method and to add another return. However, you should consider the collection protocol. Usually, there already is a method, that solves your problem. Possible methods could be: `#detect:ifFound:ifNone:` or `#detect:thenDo:ifNone:`.

=== Are there abstract classes in Smalltalk and how should I name them? ===
In Smalltalk a class is abstract when a method is implemented with "self subclassResponsibility". However, you can still create objects of this class, but this method cannot be called. A typically idiom is to extend the name with the word "Abstract". Examples in the image are: !AbstractEvent, !AbstractFont, or !AbstractSound.

== Idioms and Patterns ==
=== How to I access class variables or methods? Via classname or self class? ===


== I/O ==

== Graphic (Morphic) ==

=== How do I repeat an image in the background? ===
An image can be repeated in the Background using an !InfiniteMorph as a morph's fill-style:
{{{
aForm := Form fromFileNamed: 'picture.png'.
anInfiniteForm := InfiniteForm with: aForm.
Morph new
    extent: 500@500;
    fillStyle: anInfiniteForm;
    openInHand.
}}}

=== How do I react on deleting morphs using halos? ===
If a morph is deleted using the X in the halo menu, `Morph>>dismissViaHalo`, `Morph>>dismissMorph`, `Morph>>delete` are called. If your morph is a subclass of Morph, you can overwrite one of these. Do not forget to call the super implementation. 

=== How do I prevent a Morph from stepping directly after opening? ===

`Morph>>wantsStep` can be overwritten returning false. As a result the morph will not start stepping immediately. Nevertheless, you can start stepping with `Morph>>startStepping` later on. 


=== How do I implement a parallax scrolling for background images? ===

=== How do I change the size of an image independent from the aspect ratio? ===
A Form can be scaled using `Form>>#magnify:by:smoothing:`. The scale factor can either by a single value or a point to define the scale factor for both height and width.
The following examples shows how to change the size to 100@50 independent from the original aspect ratio:
{{{
MenuIcons helpIcon in: [:form |
    (form
        magnify: form boundingBox
        by: (100@50) / form extent
        smoothing: 1) asMorph openInHand].
}}} 

=== How do I insert morphs in the background?===

Instead of using `addMorph:` you can use the following methods to influence the z-level of morphs:
`#addMorph`, `addMorphFront:`, `#addMorph:behind:`, and `#addMorph:inFrontOf:`.

=== How do I rotate a morph? ===

To rotate a morph you can create a !TransformationMorph around your morph and change the angle using: `TransformationMorph>>angle:`

{{{
aForm := Form fromFileNamed: 'picture.png'.
anImageMorph := aForm asMorph.
aTransformMorph := TransformationMorph new asFlexOf: anImageMorph. 
aTransformMorph openInHand.
aTransformMorph angle: Float pi/4 negated.
}}}

If you want to rotate a local Resource only once at the beginning, you can create a From and rotate it using `From>>rotateBy:`
You can rotate it later on by creating another rotated copy and exchanging the from of the !ImageMorph. However, this is inperformant if used often.

{{{
aForm := Form fromFileNamed: 'picture.png'.
anImageMorph := aForm asMorph.
anImageMorph image: (aForm rotateBy:45 smoothing:10).
anImageMorph openInHand.
anImageMorph image: (aForm rotateBy:90 smoothing:1).
}}}

== Sound ==

== Image Concept ==

== Squeak ==

=== How do I change the author initials? ===
For future code changes you can change your author initials via menu as shown in the picture below.

== Seaside ==

== Gemstone ==

== Versioning (Monticello) ==

== Patterns and Idioms ==

== Other ==