Changes

When you open the document, the script is read once. It initializes and overwrites all the functions and globals with the ones you defined. Thus, '''message''' is nil. Once the '''on.paint()''' event is called, '''message''' is nil, thus, nothing is done. When you press a key that calls '''on.charIn()''' (see below for more information), '''message''' is now "Hello World" and we tell the '''platform''' that the screen has to be refreshed. Then, '''on.paint()''' is called again, '''message''' is not nil then we display it, erase '''message''' and launch a timer. Why is that ? Because if we call '''platform.window:invalidate()''' right there, we won't refresh the screen. Why again ? Just look at the pseudo-code above. We set the window as drawn after each call of on.paint(). Thus a timer is necessary to manually recall '''on.paint()''' and exit the '''on.paint()''' function to draw the screen. When the timer is ended, '''on.timer()''' is called and we refresh the screen. The screen is then redrawn but there is nothing to draw because '''message''' is nil. Thus, the graphic context lets the screen blank.

When you open the document, the script is read once. It initializes and overwrites all the functions and globals with the ones you defined. Thus, '''message''' is nil. Once the '''on.paint()''' event is called, '''message''' is nil, thus, nothing is done. When you press a key that calls '''on.charIn()''' (see below for more information), '''message''' is now "Hello World" and we tell the '''platform''' that the screen has to be refreshed. Then, '''on.paint()''' is called again, '''message''' is not nil then we display it, erase '''message''' and launch a timer. Why is that ? Because if we call '''platform.window:invalidate()''' right there, we won't refresh the screen. Why again ? Just look at the pseudo-code above. We set the window as drawn after each call of on.paint(). Thus a timer is necessary to manually recall '''on.paint()''' and exit the '''on.paint()''' function to draw the screen. When the timer is ended, '''on.timer()''' is called and we refresh the screen. The screen is then redrawn but there is nothing to draw because '''message''' is nil. Thus, the graphic context lets the screen blank.

==GC (as in Graphics Context)==

==gc (as in Graphics Context)==

Note: You need to add “gc:” before each of these commands in order to use them. ex. '''gc:setAlpha(...)'''.

Note: You need to add “gc:” before each of these commands in order to use them. ex. '''gc:setAlpha(...)'''.