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Example: Animate text with multiple selectors

This example uses the selectorValue parameter in an Expression selector with the Wiggly selector to make a string of characters flash on and off randomly.

  1. Create a new composition.
  2. Create a new text layer.
  3. In the Timeline panel, choose Opacity from the Animate menu for the text layer.
  4. Expand the text layer and its animator in the Timeline panel.
  5. Select the Range Selector and delete it.
  6. Choose Add > Selector > Wiggly next to the Animator property group for the text layer.
  7. Choose Add > Selector > Expression. If the Wiggly selector doesn’t come before the Expression selector, drag the Wiggly selector above the Expression selector.
  8. Expand the Expression Selector.
  9. Expand the Amount property to reveal the expression. The following expression appears by default: 
    selectorValue * textIndex/textTotal
  10. Replace the default expression text with the following expression: 
    r_val=selectorValue[0]; 
if(r_val < 50)r_val=0; 
if(r_val > 50)r_val=100; 
r_val
  11. Set the opacity to 0%, and preview the composition.