Let's learn to write programs with LiveCode

[richmond62]

This series of posts is based on a number of presuppositions:

1. You have never done any computer programming before.

[Or, if you have, you did not really understand what was going on]

2. Your teacher has installed LiveCode on your computer so that when you start it up it
up it looks something like this:

[I am using LiveCode 9.6.x on Macintosh, but most of the time everything will look very much
the same as on Windows or Linux]
-

[richmond62]

Let's get started by using the Menu to make a "new stack":
-

-

-
This 'stack' is really like a bit of paper on which we can draw things we want for our programming.

Why a window is called a 'stack' is interesting, but is not very important at the moment.
When it becomes important we'll explain why it is called a 'stack'.

We can make it bigger if we want to by dragging the window bigger with the mouse from the
bottom right corner.

[richmond62]

If we now look at the TOOLS on the left of our window we will see that there
are lots of things we can put on our window to help us with our program:
-

[richmond62]

We are going to start by looking at BUTTONS and FIELDS:
-

[richmond62]

Let's put a BUTTON on our window by DRAGGING one from the TOOLS:
-

-
Now, let's put a FIELD on our window by DRAGGING one from the TOOLS:
-

[richmond62]

We can use a BUTTON to TELL the computer to DO things:
-

SShot 2021-10-23 at 14.31.59.png (13.66 KiB) Viewed 4991 times

-
TELLING a computer to DO something is called INPUT
-
And we can use a FIELD for the computer to TELL us things:
-

SShot 2021-10-23 at 14.32.18.png (11 KiB) Viewed 4991 times

-
When a computer TELLS us something, that is called OUTPUT

[richmond62]

Let's get the BUTTON to ASK for some INFORMATION from US:

The FIRST thing we do is find the SCRIPT EDITOR to enter some CODE:
-

-

-
NORMALLY we use a BUTTON to get INFORMATION when we CLICK a computer mouse:
-

[richmond62]

When we have typed some CODE into a SCRIPT EDITOR we need to APPLY it:
-

-
NOW it is important that the INFORMATION a computer gets goes somewhere so we can see it.

SO it is important that we give our FIELD where we want our INFORMATION to go a NAME:

We need to open the PROPERTY INSPECTOR of our FIELD:
-

-

[richmond62]

Here we can change the NAME of our FIELD to something that makes sense to us:
-

c9.jpg (17.02 KiB) Viewed 4962 times

-
This also makes things easy when we want to send INFORMATION there:
-

-

HOWEVER, ALL we have done so far is INPUT some INFORMATION and told the computer to OUTPUT
it again WITHOUT doing any OPERATIONS.

[richmond62]

We can see this if we CLICK on the PLAY button on the TOOLS bar:
-

-

-

[richmond62]

-

[richmond62]

SO: LET'S try an OPERATION with the INFORMATION we have TOLD the computer:

BEFORE we do that we should NAME our work and SAVE it:

WE need to open the PROPERTY INSPECTOR of our work:
-

-

-
And NAME our work to something that makes sense to us:
-

c17.jpg (12.97 KiB) Viewed 4948 times

[richmond62]

And then SAVE our work:
-

[richmond62]

Now, let's CHANGE the CODE in the BUTTON:
-

-
And we will see that our OUTPUT has been changed:
-

-

[richmond62]

NOW, let's CHANGE our CODE so the OUTPUT is a bit easier to understand:
-

-