QPropertyAnimation

Overview

This provides utility functions for working with Qt animations, specifically for handling easing curves and direction properties. These utilities are commonly used when creating smooth animations in Qt applications.

Easing Curve Utility

returnAnimationEasingCurve(easingCurveName)

Converts a string name of an easing curve to the corresponding QEasingCurve type.

Parameters:

• easingCurveName (str): Name of the easing curve (case-sensitive)

Returns:

• Corresponding QEasingCurve.Type value

Supported Easing Curves:

Linear
OutQuad, InQuad, InOutQuad, OutInQuad
InCubic, OutCubic, InOutCubic, OutInCubic
InQuart, OutQuart, InOutQuart, OutInQuart
InQuint, OutQuint, InOutQuint
InSine, OutSine, InOutSine, OutInSine
InExpo, OutExpo, InOutExpo, OutInExpo
InCirc, OutCirc, InOutCirc, OutInCirc
InElastic, OutElastic, InOutElastic, OutInElastic
InBack, OutBack, InOutBack, OutInBack
InBounce, OutBounce, InOutBounce, OutInBounce

Example:

curve = returnAnimationEasingCurve("OutBack")
animation.setEasingCurve(curve)

Error Handling:

• Raises Exception if an unknown easing curve name is provided
• Raises Exception if empty string is provided

Direction Utility

returnQtDirection(direction)

Converts a string direction name to the corresponding Qt direction flag.

Parameters:

• direction (str): Either "horizontal" or "vertical" (case-sensitive)

Returns:

• Corresponding Qt.Orientation value (Qt.Horizontal or Qt.Vertical)

Example:

direction = returnQtDirection("vertical")
slider.setOrientation(direction)

Error Handling:

• Raises Exception if an unknown direction name is provided
• Raises Exception if empty string is provided

Usage Notes

1. Easing Curves:

   • Use these to create smooth animation effects
   • Different curves produce different acceleration/deceleration effects
   • Common choices:
     • OutQuad/OutCubic: Smooth deceleration
     • InOutBack: Slight overshoot effect
     • OutBounce: Playful bounce effect

2. Directions:

   • Used for widgets like sliders, layouts, and progress bars
   • Match the direction string exactly ("horizontal" or "vertical")

3. Error Handling:

   • Always wrap calls in try/except blocks when processing user input
   • Provide user feedback when invalid values are entered

Example Workflow

from qtpy.QtCore import QPropertyAnimation

# Create animation with easing curve
animation = QPropertyAnimation(widget, b"geometry")
animation.setEasingCurve(returnAnimationEasingCurve("OutBack"))
animation.setDuration(1000)

# Set up a vertical slider
slider = QSlider()
slider.setOrientation(returnQtDirection("vertical"))