ActionScript - redisplaying data up to a certain point

[Chris82]

Hello all

First post in this forum for me.

I will try to explain the problem I am currently facing:

I am trying to plot data stored in an array. I am able to plot the complete data at once but I would like to be able to step back and for in the display.
I have created a variable "current" which is incremented by a click on one button and the data is plotted up to "current". This works but I cannot get it to work to step back when I click the button I created for this whichs decreases "current" by one.

Example:
- the user has clicked three times on the button "next"
=> "current" is 3
=> the first three elements of the data are plotted

- the user now clicks once the button "prev"
=> "current" is 2
=> now only the first two elements should be displayed

The movieclip is created using _root.createEmptyMovieClip(...);

On a related note, I noticed that there seems to bit of a performance hit if I create several MovieClips using createEmptyMovieClip(). The moving around of a zoomed clip is really slow. I have four arrays to plot and created a MovieClip for each in order to make it easier to show or disable each.
Did somebody also encouter this?

I hope, I explained it properly.

Thanks in advance,
Christian

[aaron.martone]

I'd recommend making the "current" vairable global.

_global.current = 0;

Then for the buttons you'd have;

on(release){
_global.current += 1;
}
// above code for the incrementing button

on(release){
_global.current -= 1;
}
// above code for the decrementing button

If you had a button that you press to output the data, you could do

on(release){
displayOutput();
}

And the function would be something like...

function displayOutput(){
for (i=0; i<_global.current; i++) {
trace(Array[" + i + "] : " + arrName[i] + "." );
}
}

Eh?

[Chris82]

Hi.

I'd recommend making the "current" vairable global.

[...]

Eh?

Thank you for your answer

What you posted is more or less what I have come up with. I didn't make current global but this does not seem to be the problem. I will post a simplified version of the code I have:

// "global" values for drawing the lines
var xoffset = 10;
var yoffset = 10;
var between = 10;
var scaley = 1.5;
var ROUNDS = 25;
var current = 0;

// two records
var records =  new Array(0, 12, 8, 12, 20, -10, 30, 12, 40, -20, -14, -10, 8, 4, 0);
var records2 = new Array(0, 14, 2, 1, 30, -1, 23, 32, 43, -20, -30, -10, 3, 4, 0);

// implementation of Java's drawline
MovieClip.prototype.drawLine = function(x1, y1, x2, y2) {
	this.moveTo(x1, y1);
	this.lineTo(x2, y2);
}

// plot data which is stored in an array
MovieClip.prototype.plotData = function(records) {
	for (var i = 0; i < Math.min(current, records.length); i++) {
		// the next point in the array 
		var j = Math.min(i + 1, records.length - 1);
		
		this.drawLine(
			i * between, 
			scaley * -records[i], 
			j * between, 
			scaley * -records[j]
		);
	}
}

// create to movie clips
var plot1 = _root.createEmptyMovieClip("p1", 1);
var plot2 = _root.createEmptyMovieClip("p2", 2);

plot1.lineStyle(1, 0xFF0000, 100);
plot2.lineStyle(1, 0x00FF00, 100);

plot1._x = xoffset;
plot1._y = 40;

plot2._x = xoffset;
plot2._y = 40;

plot1.plotData(records);
plot2.plotData(records2);

And this is the code for [previous] and [next] buttons I use:

previous:

on(release) {
	current = Math.max(0, current - 1);
	plot1.plotData(records);
	plot2.plotData(records2);
}

next:

on(release) {
	current = Math.min(current + 1, ROUNDS);
	plot1.plotData(records);
	plot2.plotData(records2);
}

Now when I click on next (the second button in the attached file, the next points are drawn. However clicking on previous (first button) it doesn't go back.
Perhaps I have to clear the already drawn lines and display these afterwards?

Thanks,
Christian

[Chris82]

I have almost solved my problem.
Going back and forth is possible now.
The only problem currently is when I click on one of the buttons on upper right and hit back several times and hit the same button again, the corresponding line does not show up at once. I have to click back / for again to make it visible.

link: http://christian-sobetzko.de/plotter.html