Flashing is basically animation. All you need is an ImageMorph and to add
stepping using the step method.
step is the method that does the animation loop (step = frame)
stepTime you return how much time will be spend be spend per step
this is my step method from my project ChronosManager which basically does
the seconds indicator animation, each second basically display a different
image that is appropriate for that second.
step
"super step."
self managerModel mode = 'clock'
ifTrue: [ time := DateAndTime current.
timeStr color: Color white ].
self managerModel mode = 'timer' | (self managerModel mode =
'stopwatch')
ifTrue:
[ time := ('0:' , self managerModel timeDisplay) asDuration
minutes asDuration.
self managerModel phase = 'work'
ifTrue: [ timeStr color: Color green ].
self managerModel phase = 'break'
ifTrue: [ timeStr color: Color red ] ].
secondsTimer form: (self secondsTimerForm at: time seconds + 1).
self setTimeLabel.
World submorphs do: [ :each| (each isKindOf: TaskbarMorph) ifTrue:
[each updateTaskButtons]]
stepTime
^ 1000
you use the form: message to change the image of the morph
form is create like this
Form fromFileNamed: wp /
('images/panels/mainPanel/secondsTimer/secondsTimer0001.png')
wd here references the pharo directory (working directory) which you can
assign like this
wd := FileSystem disk workingDirectory .
On Mon, Nov 28, 2016 at 10:43 PM William L. Cleveland <w...@columbia.edu>
wrote:
> I want to write code to flash a color image of a person in a window for a
> short period of time. The duration of the flash is important, not the
> frequency of the flashes, which will be low and probably controlled by
> pressing a key.
>
> Ideally, the duration should be an integral number of frames, starting
> from 1 and increasing to a much larger number. With a 60 Hz monitor, one
> frame would be 0.0167 seconds. The images would be low to moderate
> resolution, e.g. 70K to 1 Mb
>
> Can this be done entirely in Pharo or would it be necessary to use the
> Unified FFI with operating system commands? If it can be done in Pharo,
> what are the classes needed to display an image filed in from the hard
> drive?
>
> I am using a 27 inch iMAC (10.11.6) with 4GHz, 8 GB ram, and AMD Radeon
> R9 M395X 4096 MB video card. Pharos is new to me but I wrote Smalltalk code
> with VisualWorks a few years back.
>
> Thanks very much.
>
> Lou Cleveland
>
