Animate ProgressBar update in Android

Question

I am using a ProgressBar in my application which I update in onProgressUpdate of an AsyncTask. So far so good.

What I want to do is to animate the prog

Answer 1

Here is an improved version of a.ch. solution where you can also use rotation for circular ProgressBar. Sometimes it's required to set constant progress and change only rotation or even both progress and rotation. It is also possible to force clockwise or counter clockwise rotation. I hope it will help.

public class ProgressBarAnimation extends Animation {
    private ProgressBar progressBar;
    private int progressTo;
    private int progressFrom;
    private float rotationTo;
    private float rotationFrom;
    private long animationDuration;
    private boolean forceClockwiseRotation;
    private boolean forceCounterClockwiseRotation;

    /**
     * Default constructor
     * @param progressBar ProgressBar object
     * @param fullDuration - time required to change progress/rotation
     */
    public ProgressBarAnimation(ProgressBar progressBar, long fullDuration) {
        super();
        this.progressBar = progressBar;
        animationDuration = fullDuration;
        forceClockwiseRotation = false;
        forceCounterClockwiseRotation = false;
    }

    /**
     * Method for forcing clockwise rotation for progress bar
     * Method also disables forcing counter clockwise rotation
     * @param forceClockwiseRotation true if should force clockwise rotation for progress bar
     */
    public void forceClockwiseRotation(boolean forceClockwiseRotation) {
        this.forceClockwiseRotation = forceClockwiseRotation;

        if (forceClockwiseRotation && forceCounterClockwiseRotation) {
            // Can't force counter clockwise and clockwise rotation in the same time
            forceCounterClockwiseRotation = false;
        }
    }

    /**
     * Method for forcing counter clockwise rotation for progress bar
     * Method also disables forcing clockwise rotation
     * @param forceCounterClockwiseRotation true if should force counter clockwise rotation for progress bar
     */
    public void forceCounterClockwiseRotation(boolean forceCounterClockwiseRotation) {
        this.forceCounterClockwiseRotation = forceCounterClockwiseRotation;

        if (forceCounterClockwiseRotation && forceClockwiseRotation) {
            // Can't force counter clockwise and clockwise rotation in the same time
            forceClockwiseRotation = false;
        }
    }

    /**
     * Method for setting new progress and rotation
     * @param progress new progress
     * @param rotation new rotation
     */
    public void setProgressAndRotation(int progress, float rotation) {

        if (progressBar != null) {
            // New progress must be between 0 and max
            if (progress < 0) {
                progress = 0;
            }
            if (progress > progressBar.getMax()) {
                progress = progressBar.getMax();
            }
            progressTo = progress;

            // Rotation value should be between 0 and 360
            rotationTo = rotation % 360;

            // Current rotation value should be between 0 and 360
            if (progressBar.getRotation() < 0) {
                progressBar.setRotation(progressBar.getRotation() + 360);
            }
            progressBar.setRotation(progressBar.getRotation() % 360);

            progressFrom = progressBar.getProgress();
            rotationFrom = progressBar.getRotation();

            // Check for clockwise rotation
            if (forceClockwiseRotation && rotationTo < rotationFrom) {
                rotationTo += 360;
            }

            // Check for counter clockwise rotation
            if (forceCounterClockwiseRotation && rotationTo > rotationFrom) {
                rotationTo -= 360;
            }

            setDuration(animationDuration);
            progressBar.startAnimation(this);
        }
    }

    /**
     * Method for setting only progress for progress bar
     * @param progress new progress
     */
    public void setProgressOnly(int progress) {
        if (progressBar != null) {
            setProgressAndRotation(progress, progressBar.getRotation());
        }
    }

    /**
     * Method for setting only rotation for progress bar
     * @param rotation new rotation
     */
    public void setRotationOnly(float rotation) {
        if (progressBar != null) {
            setProgressAndRotation(progressBar.getProgress(), rotation);
        }
    }

    @Override
    protected void applyTransformation(float interpolatedTime, Transformation t) {
        float progress = progressFrom + (progressTo - progressFrom) * interpolatedTime;
        float rotation = rotationFrom + (rotationTo - rotationFrom) * interpolatedTime;

        // Set new progress and rotation
        if (progressBar != null) {
            progressBar.setProgress((int) progress);
            progressBar.setRotation(rotation);
        }
    }
}

Usage:

ProgressBarAnimation progressBarAnimation = new ProgressBarAnimation(progressBar, 1000);

// Example 1
progressBarAnimation.setProgressAndRotation(newProgress, newRotation);

// Example 2
progressBarAnimation.setProgressOnly(newProgress);

// Example 3
progressBarAnimation.setRotationOnly(newRotation);