How to check by name if a slider exist on a layer ?

[Dan Ebberts]

Expression or script? Something like this should work for an expression:


try{
thisComp.layer("Layer Name").effect("Slider Control")("Slider");
exists = true;
}catch(err){
exists = false;
}


It would be similar for a script.

Dan

[Tal Arbiv]

Thank you so much Dan!

yes its scripting…

The second question i had was how can i tell how many dimensions a property has ?
i’m applying an expression to layers and i want the expression to change according to the dimensions…

lets take wiggle for example
if there is a better way to do this please share…

Thanks a lot again!

var expression1 = "wiggle (10,10)";
var expression2 = "w=wiggle (10,10);[w[0],w[0]]";
var expression3 = "w=wiggle (10,10);[w[0],w[0],w[0]]";

for (i=0; i <= sellayers.length-1; i++){
for (p=0; p < = selprop.length-1; p++){
//missing query
selprop[p].expression = //expressionX;
}


[Dan Ebberts]

I think I’d do something like this:

var val = myProp.valueAtTime(0,false);
var numDim = val instanceof Array ? val.length : 1;

Dan

[Tal Arbiv]

i tried it and it breaks…

something about that valueAtTime method stops the loop that goes through the layers

var myComp = app.project.activeItem;
var sellayers = myComp.selectedLayers;
var selprop = myComp.selectedProperties;

for (i=0; i <= sellayers.length-1; i++){
for (p=0; p <= selprop.length-1; p++){
selprop[p].expression =("1"); //WORKS GREAT
alert (selprop[p].valueAtTime(0,false)); // DOSNT WORK breaks the loop after the first layer
}
}


[Dan Ebberts]

You may have some properties selected that can’t have expressions, so I’d make sure that myProp.canSetExpression is true before doing the other tests.

Dan

[Tal Arbiv]

This will be great to add thanks.
but the problem wasn’t the expression. putting expressions works great for all layers and all properties, the valueAtTime line doesn’t.
what am i missing?

[Dan Ebberts]

I don’t think you want to loop both selected layers and selected properties. This seems to work for me with everything I could throw at it:


var myComp = app.project.activeItem;
var selprop = myComp.selectedProperties;

for (p=0; p <= selprop.length-1; p++){
if (selprop[p].canSetExpression){
selprop[p].expression =("value");
alert (selprop[p].valueAtTime(0,true));
}
}


Dan

[Tal Arbiv]

wow, i was sure i tried that at the beginning…
maybe i needed some operation to be made at the same time to the layers… anyway, it works now,
really appreciate your help!