PhotographicPrintAnimator realize a beautiful photographic print animation as described in the Material design spec (http://www.google.com/design/spec/patterns/loading-images.html#loading-images-loading-images)
Text file (2 KB): gistfile1.txt
import android.animation.ValueAnimator;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.view.animation.AccelerateDecelerateInterpolator;
import android.view.animation.Interpolator;
import android.widget.ImageView;
import java.lang.ref.SoftReference;
public class PhotographicPrintAnimator {
final SoftReference<ImageView> mView;
final ColorMatrix mColorMatrix;
final float[] mBrightness = new float[]
{
1, 0, 0, 0, 0,
0, 1, 0, 0, 0,
0, 0, 1, 0, 0,
0, 0, 0, 1, 0
};
final ColorMatrix mBrightnessColorMatrix;
final Interpolator mInterpolator;
public PhotographicPrintAnimator(ImageView v) {
mView = new SoftReference<ImageView>(v);
mColorMatrix = new ColorMatrix();
mBrightnessColorMatrix = new ColorMatrix();
mInterpolator = new AccelerateDecelerateInterpolator();
}
public void start(int duration) {
final ValueAnimator v = ValueAnimator.ofFloat(0f, 1f);
final ValueAnimator v2 = ValueAnimator.ofFloat(0f, 1f);
v.setInterpolator(mInterpolator);
v.setDuration(duration);
v.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
mColorMatrix.setSaturation(animation.getAnimatedFraction());
if (mView.get() != null) {
mView.get().setColorFilter(new ColorMatrixColorFilter(mColorMatrix));
} else {
v.cancel();
v2.cancel();
}
}
});
v2.setInterpolator(mInterpolator);
v2.setDuration((int) (duration * 0.75));
v2.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
float brightness = (1f - animation.getAnimatedFraction()) * 255;
mBrightness[4] = brightness;
mBrightness[9] = brightness;
mBrightness[14] = brightness;
mBrightnessColorMatrix.set(mBrightness);
mColorMatrix.postConcat(mBrightnessColorMatrix);
if (mView.get() != null) {
mView.get().setColorFilter(new ColorMatrixColorFilter(mColorMatrix));
} else {
v.cancel();
v2.cancel();
}
}
});
if (mView.get() != null) {
mView.get().setAlpha(0f);
mView.get().animate().alpha(1.0f).setDuration(duration / 2);
v.start();
v2.start();
}
}
}