进度条动画AE教程 After Effects – Advanced Progress Bar Rig Tutorial在AE中用表达式来控制进度条的读取动画，包含数字的变化等In this tutorial, Mike Ridolfi from Mobox Graphics will show you how to rig a progress bar / loading bar or percentage bar in Adobe After Effects.

This percentage bar / progress bar uses a Slider Control to determine the the scale of the progress bar, the percentage, and the position of the percentage indicator.

用到的表达式：thisComp.layer(“Null”).effect(“Slider Control”)(“Slider”).value.toFixed(0) + “%”x = (x2) – (100-Slider)*(x2-x1)/100