Answers.Body: <p>I found out - <strong>.value</strong> after slider.effect("Slider Control").property("Slider") and it works.</p>
  
  <pre><code>var a = slider.effect("Slider Control").property("Slider").value
  </code></pre>
  
Answers.ContentLicense: CC BY-SA 3.0
Answers.CreationDate: 2016-04-25T07:58:44.903Z
Answers.LastActivityDate: 2016-04-25T07:58:44.903Z
Answers.UserDisplayName: 49volro
Body: <p>I'm newbie in After Effects. I've learned how to control slider from expressions. Now I need to get value of slider in script (jsx/extendscript). How can I achieve that?</p>
  
  <p>I've tried (in *.jsx): <code>var a = comp.layer("Slider 1").effect("Slider Control")("Slider")[0];</code></p>
  
  <p>Result: </p>
  
  <blockquote>
    <p>After Effects error: Unable to call "setValue" because of parameter 1.
    Value "NaN" of element 0 in the array is not a valid float.</p>
  </blockquote>
  
  <p>It means that value of slider is not set yet?</p>
  
  <p>Thanks</p>
  
  <p><strong>EDIT:</strong></p>
  
  <p>Here is a example:</p>
  
  <pre><code>var slider = comp.layers.addNull();
  slider.name = "Slider";
  slider.effect.addProperty("ADBE Slider Control")("Slider");
  slider.effect("Slider Control").property("Slider").setValue(100);
  
  var a = slider.effect("Slider Control").property("Slider");
  var titleTriangle = comp.layers.addShape();
  titleTriangle.name = ("Title Triangle");
  var titleTriangleGroup = titleTriangle.property("Contents").addProperty("ADBE Vector Group");
  var titleTriangleFill= titleTriangleGroup.property("Contents").addProperty("ADBE Vector Graphic - Fill");
  titleTriangleFill.property("Color").setValue([0.68,0.29,0.29,1]);
  
  // using 'a' here
  titleTriangle.property("Position").setValue([a,188]);
  </code></pre>
  
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-04-24T12:31:07.947Z
Comments.Text: Please paste all code here. It is difficult to understand, where can be problem, when you are seeing only part of code.
Comments.UserDisplayName: Shultc
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-04-24T14:38:30.583Z
Comments.Text: @Shultc, thank you for response. I have added an example.
Comments.UserDisplayName: 49volro
Comments.ContentLicense: CC BY-SA 3.0
Comments.CreationDate: 2016-04-26T04:57:20.323Z
Comments.Text: Sounds like you need to know about Redefinery's **RD_Gimme_Props** script. It's a script that allows you to find the correct path for any composition element: http://bit.ly/1XTIzh0 There's a whole bunch of tools there for extendscript developers.
Comments.UserDisplayName: stib
Tags: <after-effects><after-effects-expressions>
Title: After Effects: controlling slider in ExtendScript
UserDisplayName: 49volro
ThreadText: # After Effects: controlling slider in ExtendScript
  
  (Asked by: username_0 on 2016-04-24)
  
  I'm newbie in After Effects. I've learned how to control slider from expressions. Now I need to get value of slider in script (jsx/extendscript). How can I achieve that?
  
  I've tried (in \*.jsx): `var a = comp.layer("Slider 1").effect("Slider Control")("Slider")[0];`
  
  Result:
  
  > After Effects error: Unable to call "setValue" because of parameter 1.
  > Value "NaN" of element 0 in the array is not a valid float.
  
  It means that value of slider is not set yet?
  
  Thanks
  
  **EDIT:**
  
  Here is a example:
  
  ```
  var slider = comp.layers.addNull();
  slider.name = "Slider";
  slider.effect.addProperty("ADBE Slider Control")("Slider");
  slider.effect("Slider Control").property("Slider").setValue(100);
  
  var a = slider.effect("Slider Control").property("Slider");
  var titleTriangle = comp.layers.addShape();
  titleTriangle.name = ("Title Triangle");
  var titleTriangleGroup = titleTriangle.property("Contents").addProperty("ADBE Vector Group");
  var titleTriangleFill= titleTriangleGroup.property("Contents").addProperty("ADBE Vector Graphic - Fill");
  titleTriangleFill.property("Color").setValue([0.68,0.29,0.29,1]);
  
  // using 'a' here
  titleTriangle.property("Position").setValue([a,188]);
  
  ```
  
  **Tags:** after-effects, after-effects-expressions
  
  > **Comments:**
  > **username_1**: Please paste all code here. It is difficult to understand, where can be problem, when you are seeing only part of code.  
  > **username_0**: @username_1, thank you for response. I have added an example.  
  > **username_2**: Sounds like you need to know about Redefinery's **RD_Gimme_Props** script. It's a script that allows you to find the correct path for any composition element: http://bit.ly/1XTIzh0 There's a whole bunch of tools there for extendscript developers.  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_0 on 2016-04-25. Score: 3 | Accepted answer
  
  I found out - **.value** after slider.effect("Slider Control").property("Slider") and it works.
  
  ```
  var a = slider.effect("Slider Control").property("Slider").value
  
  ```
  
  
  ---
  
  