Develop Reference

animate view translationY on bottomsheet scroll

I would like to smoothly animate some views Y position based on the user scrolling a bottom sheet.
http://imgur.com/dVBlh83
However the animation is slightly jerky.
This is probably because scrolling a bottomsheet gives me a slideOffset at some interval, which is too infrequent to setTranlationY like I'm currently doing.
Is there a better way to do this.
Bottom sheet callback
BottomSheetBehavior.BottomSheetCallback() {
#Override public void onSlide(#NonNull View bottomSheetView, float slideOffset) {
int offset = (int) (slideOffset * 100);
if (offset > 0) {
scrollingHeaderView.animate(offset);
}
}
});
scrollingHeaderView
public void animate(int offset) {
position = -(offset / 2);
arrow.setTranslationY(offset * ANIMATION_RATIO_ARROW);
detailView.setTranslationY(offset * ANIMATION_RATIO);
}
I have tried using ObjectAnimator to create lots of small animations at each step.
ObjectAnimator.ofFloat(arrow, "translationY", arrow.getTranslationY(), position * ANIMATION_RATIO_ARROW).start();

in case it helps anyone else. I got it looking much better.
First i set the ration by pixel * range of values i'd get. So offset will be 0 -> 100. Mutliplied by the dp i want the view to move
private static int ANIMATION_RANGE = 100;
arrowScale = -(getResources().getDimensionPixelOffset(R.dimen.arrow_distance) / ANIMATION_RANGE);
containerScale = -(getResources().getDimensionPixelOffset(R.dimen.detail_distance) / ANIMATION_RANGE);
then as the value changes i set this using translationY
arrow.setTranslationY(position * arrowScale);
detailView.setTranslationY(position * containerScale);
I also needed a reset method, which animate back to the original position
public void reset() {
arrow.animate().setDuration(100).translationY(0);
detailView.animate().setDuration(100).translationY(0);
}

LibGDX Rotate 2D image with touchDragged() event

Objective: to rotate an image in the center of the screen with movement equal to left or right touchDragged event.
Right now I have a basic Stage that is created and adds an actor (centerMass.png) to the stage. it is created and rendered like this:
public class Application extends ApplicationAdapter {
Stage stageGamePlay;
#Override
public void create () {
//setup game stage variables
stageGamePlay = new Stage(new ScreenViewport());
stageGamePlay.addActor(new CenterMass(new Texture(Gdx.files.internal("centerMass.png"))));
Gdx.input.setInputProcessor(stageGamePlay);
}
#Override
public void render () {
Gdx.gl.glClearColor(255f/255, 249f/255, 236f/255, 1f);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
//before drawing, updating actions that have changed
stageGamePlay.act(Gdx.graphics.getDeltaTime());
stageGamePlay.draw();
}
}
I then have a separate class file that contains the CenterMass class, extending Image. I am familiar enough to know I could extend Actor, but I am not sure the benefit I would gain using Actor vs Image.
In the CenterMass class I create the texture, set bounds, set touchable and center it on the screen.
Inside CenterMass class I also have an InputListener listening for events. I have an override set for touchDragged where I am trying to get the X and Y of the drag, and use that to set the rotate actions accordingly. That class looks like this:
//extend Image vs Actor classes
public class CenterMass extends Image {
public CenterMass(Texture centerMassSprite) {
//let parent be aware
super(centerMassSprite);
setBounds(getX(), getY(), getWidth(), getHeight());
setTouchable(Touchable.enabled);
setPosition(Gdx.graphics.getWidth()/2, Gdx.graphics.getHeight()/2);
setRotation(90f);
addListener(new InputListener(){
private int dragX, dragY;
private float duration;
private float rotateBy = 30f;
#Override
public void touchDragged(InputEvent event, float x, float y, int pointer) {
//get
float dX = (float)(x-dragX)/(float)Gdx.graphics.getWidth();
float dY = (float)(dragY-y)/(float)Gdx.graphics.getHeight();
duration = 1.0f; // 1 second
Actions.sequence(
Actions.parallel(
Actions.rotateBy(rotateBy, duration),
Actions.moveBy( dX, dY, duration)
)
);
}
});
}
#Override
protected void positionChanged() {
//super.positionChanged();
}
#Override
public void draw(Batch batch, float parentAlpha) {
//draw needs to be available for changing color and rotation, I think
batch.setColor(this.getColor());
//cast back to texture because we use Image vs Actor and want to rotate and change color safely
((TextureRegionDrawable)getDrawable()).draw(batch, getX(), getY(),
getOriginX(), getOriginY(),
getWidth(), getHeight(),
getScaleX(), getScaleY(),
getRotation());
}
#Override
public void act(float delta) {
super.act(delta);
}
}
The Problem:
I have not been able to get it to rotate the way I would like. I have been able to get it to shift around in unpredictable ways. Any guidance would be much appreciated.

As from you code it seems everything is good. except you don't set any origin of the image. without setting the origin it is by default set to 0,0.(bottom left of your image)
So if yow want to rotate the image with origin to centre you have to set the origin to imageWidth/2. imageHeight/2.
setOrigin(imageWidth/2,imageHeight/2)// something like this

Cube Flip animation for Fragments on Android

I want to implement a basic 3d cube and rotate it by 90degrees either horizontally or vertically on Touch. What i want to implement is something similar to what is shown in the image below.
I've achieved this using ViewPager's ViewTransformer
But I am not happy with the result. The animation is not very smooth, and i cannot flip it, i have to drag my finger across the entire widht of the screen to rotate the cube.
I want to just flip it, but am not able to achieve it.
I've used BTGridPager-Android to achieve the above. But as mentioned, its not very convincing.
Here is my ViewTransformer code:
public abstract class ABaseTransformer implements PageTransformer {
#Override
public void transformPage(View page, float position) {
onPreTransform(page, position);
onTransform(page, position);
onPostTransform(page, position);
}
protected void onPreTransform(View page, float position) {
final float width = page.getWidth();
page.setRotationX(0);
page.setRotationY(0);
page.setRotation(0);
page.setScaleX(1);
page.setScaleY(1);
page.setPivotX(0);
page.setPivotY(0);
page.setTranslationY(0);
page.setTranslationX(isPagingEnabled() ? 0f : -width * position);
if (hideOffscreenPages()) {
page.setAlpha(position <= -1f || position >= 1f ? 0f : 1f);
} else {
page.setAlpha(1f);
}
}
public class HorizontalCubeOutTransformer extends ABaseTransformer {
#Override
protected void onTransform(View view, float position) {
final float normalizedposition = Math.abs(1 - Math.abs(position));
view.setPivotX(position < 0f ? view.getWidth() : 0f);
view.setPivotY(view.getHeight() * 0.5f);
view.setRotationY(90f * position);
view.setAlpha(normalizedposition);
}
#Override
public boolean isPagingEnabled() {
return true;
}
}
public class VerticalCubeOutTransformer extends ABaseTransformer {
#Override
protected void onTransform(View view, float position) {
final float normalizedposition = Math.abs(Math.abs(position) - 1);
view.setAlpha(normalizedposition);
view.setTranslationX(view.getWidth() * -position);
view.setTranslationY(position * view.getHeight());
view.setPivotX(view.getWidth() * 0.5f);
view.setPivotY(position < 0f ? view.getHeight() : 0f);
view.setRotationX(90f * -position);
}
#Override
public boolean isPagingEnabled() {
return false;
}
}
What I would like to know is how to rotate the cube on the flip gesture.
Note: I would like to achieve this without OpenGL or SurfaceView.
UPDATE:
till now i have implemented the cube flip using fragmenttransactionExtended but now i got some other problem, as the current fragment disappears as soon as the flip begins

You can use FragmentTransactionExtended
FragmentTransactionExtended
it provides all types of animations between frgaments

Scaling a right aligned layout doesn't work as expected

I have a RelativeLayout with a ImageView inside it, it is aligned to the right of the screen with
android:layout_alignParentRight="true"
I then apply an animation to the layout, that will scale it to twice it size (on X-axis), but for some reason the alignment is broken and the layout (and image within it) stretches outside of the screen to the right. I was expecting it to grow to the left since it is aligned to the parent right.
I guess I could apply a translate to -X at the same time, but there are problems with this as well (1. it´s a bit complicated to compute, 2. the fillAfter never seems to work when using an AnimationSet).
Does anyone know how to solve this problem smoothly? :)

Apparently, Androids scaling is doing all sorts of bad stuff, for example it does not scale a 9-patch correct. Here is a custom animation for scaling that will solve the above and is compatible with 9-patch images. I also got some info here for the basics, this is just a rewrite of his solution: How to implement expandable panels in Android?
public class ExpandAnimation extends Animation
{
private final int mStartWidth;
private final int mDeltaWidth;
private View view;
public ExpandAnimation(View view, int startWidth, int endWidth)
{
mStartWidth = startWidth;
mDeltaWidth = endWidth - startWidth;
this.view = view;
}
#Override
protected void applyTransformation(float interpolatedTime, Transformation t)
{
android.view.ViewGroup.LayoutParams lp = view.getLayoutParams();
lp.width = (int) (mStartWidth + mDeltaWidth * interpolatedTime);
view.setLayoutParams(lp);
view.invalidate();
}
#Override
public boolean willChangeBounds()
{
return true;
}
}

Creating a 3D flip animation in Android using XML

I have created a 3D flip of a view using this android tutorial
However, I have done it programmatically and I would like to do it all in xml, if possible. I am not talking about simply shrinking a view to the middle and then back out, but an actual 3D flip.
Is this possible via xml?

Here is the answer, though it only works with 3.0 and above.
1) Create a new resources folder called "animator".
2) Create a new .xml file which I will call "flipping". Use the following xml code:
<?xml version="1.0" encoding="utf-8"?>
<objectAnimator xmlns:android="http://schemas.android.com/apk/res/android"
android:valueFrom="0" android:valueTo="360" android:propertyName="rotationY" >
</objectAnimator>
No, the objectAnimator tags do not start with an uppercase "O".
3) Start the animation with the following code:
ObjectAnimator anim = (ObjectAnimator) AnimatorInflater.loadAnimator(mContext, R.animator.flipping);
anim.setTarget(A View Object reference goes here i.e. ImageView);
anim.setDuration(3000);
anim.start();
I got all this from here.

Since the answers to this question are fairly dated, here is a more modern solution relying on ValueAnimators.
This solution implements a true, visually appealing 3D-flip, because it not just flips the view, but also scales it while it is flipping (this is how Apple does it).
First we set up the ValueAnimator:
mFlipAnimator = ValueAnimator.ofFloat(0f, 1f);
mFlipAnimator.addUpdateListener(new FlipListener(frontView, backView));
And the corresponding update listener:
public class FlipListener implements ValueAnimator.AnimatorUpdateListener {
private final View mFrontView;
private final View mBackView;
private boolean mFlipped;
public FlipListener(final View front, final View back) {
this.mFrontView = front;
this.mBackView = back;
this.mBackView.setVisibility(View.GONE);
}
#Override
public void onAnimationUpdate(final ValueAnimator animation) {
final float value = animation.getAnimatedFraction();
final float scaleValue = 0.625f + (1.5f * (value - 0.5f) * (value - 0.5f));
if(value <= 0.5f){
this.mFrontView.setRotationY(180 * value);
this.mFrontView.setScaleX(scaleValue);
this.mFrontView.setScaleY(scaleValue);
if(mFlipped){
setStateFlipped(false);
}
} else {
this.mBackView.setRotationY(-180 * (1f- value));
this.mBackView.setScaleX(scaleValue);
this.mBackView.setScaleY(scaleValue);
if(!mFlipped){
setStateFlipped(true);
}
}
}
private void setStateFlipped(boolean flipped) {
mFlipped = flipped;
this.mFrontView.setVisibility(flipped ? View.GONE : View.VISIBLE);
this.mBackView.setVisibility(flipped ? View.VISIBLE : View.GONE);
}
}
That's it!
After this setup you can flip the views by calling
mFlipAnimator.start();
and reverse the flip by calling
mFlipAnimator.reverse();
If you want to check if the view is flipped, implement and call this function:
private boolean isFlipped() {
return mFlipAnimator.getAnimatedFraction() == 1;
}
You can also check if the view is currently flipping by implementing this method:
private boolean isFlipping() {
final float currentValue = mFlipAnimator.getAnimatedFraction();
return (currentValue < 1 && currentValue > 0);
}
You can combine the above functions to implement a nice function to toggle the flip, depending on if it is flipped or not:
private void toggleFlip() {
if(isFlipped()){
mFlipAnimator.reverse();
} else {
mFlipAnimator.start();
}
}
That's it! Simple and easy. Enjoy!

I have created a simple program for creating flip of view like :
In Activity you have to create this method, for adding flip_rotation in view.
private void applyRotation(View view)
{
final Flip3dAnimation rotation = new Flip3dAnimation(view);
rotation.applyPropertiesInRotation();
view.startAnimation(rotation);
}
for this, you have to copy main class used to provide flip_rotation.
import android.graphics.Camera;
import android.graphics.Matrix;
import android.util.Log;
import android.view.View;
import android.view.animation.AccelerateInterpolator;
import android.view.animation.Animation;
import android.view.animation.Transformation;
public class Flip3dAnimation extends Animation {
private final float mFromDegrees;
private final float mToDegrees;
private final float mCenterX;
private final float mCenterY;
private Camera mCamera;
public Flip3dAnimation(View view) {
mFromDegrees = 0;
mToDegrees = 720;
mCenterX = view.getWidth() / 2.0f;
mCenterY = view.getHeight() / 2.0f;
}
#Override
public void initialize(int width, int height, int parentWidth,
int parentHeight) {
super.initialize(width, height, parentWidth, parentHeight);
mCamera = new Camera();
}
public void applyPropertiesInRotation()
{
this.setDuration(2000);
this.setFillAfter(true);
this.setInterpolator(new AccelerateInterpolator());
}
#Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
final float fromDegrees = mFromDegrees;
float degrees = fromDegrees
+ ((mToDegrees - fromDegrees) * interpolatedTime);
final float centerX = mCenterX;
final float centerY = mCenterY;
final Camera camera = mCamera;
final Matrix matrix = t.getMatrix();
camera.save();
Log.e("Degree",""+degrees) ;
Log.e("centerX",""+centerX) ;
Log.e("centerY",""+centerY) ;
camera.rotateY(degrees);
camera.getMatrix(matrix);
camera.restore();
matrix.preTranslate(-centerX, -centerY);
matrix.postTranslate(centerX, centerY);
}
}

The tutorial or the link by om252345 don't produce believable 3D flips. A simple rotation on the y-axis isn't what's done in iOS. The zoom effect is also needed to create that nice flip feel. For that, take a look at this example.
There is also a video here.

One of the better solution to flip the image with out use of the resource animation , is as follow:-
ObjectAnimator animation = ObjectAnimator.ofFloat(YOUR_IMAGEVIEW, "rotationY", 0.0f, 360f); // HERE 360 IS THE ANGLE OF ROTATE, YOU CAN USE 90, 180 IN PLACE OF IT, ACCORDING TO YOURS REQUIREMENT
animation.setDuration(500); // HERE 500 IS THE DURATION OF THE ANIMATION, YOU CAN INCREASE OR DECREASE ACCORDING TO YOURS REQUIREMENT
animation.setInterpolator(new AccelerateDecelerateInterpolator());
animation.start();

The simplest way to do it is using ViewPropertyAnimator
mImageView.animate().rotationY(360f);
Using the fluent interface you can build more complex and exciting animation.
E.g. you can enable hardware acceleration just call withLayer() method(API 16). More here
If you want to figure out how to create 3d flick animation, please follow here and here
I implemended my own solution only for a research. It includes: cancelation, accelleration, support API >= 15 and is based on Property Animation.
The entire animation includes 4 parts, 2 for each side.
Every objectAnimator has a listener that defines current animation index and represents an image in the onAnimationStart and current play time value in the onAnimationCancel.
It looks like
mQuarterAnim1.addListener(new AnimatorListenerAdapter() {
#Override
public void onAnimationStart(Animator animation) {
mQuarterCurrentAnimStartIndex = QUARTER_ANIM_INDEX_1;
mImageView.setImageResource(mResIdFrontCard);
}
#Override
public void onAnimationCancel(Animator animation) {
mQuarterCurrentAnimPlayTime = ((ObjectAnimator) animation).getCurrentPlayTime();
}
});
For start set call
mAnimatorSet.play(mQuarterAnim1).before(mQuarterAnim2)
If AnimatorSet was canceled we can calculate delta and run the reverse animation relying on the current index animation and the current play time value.
long degreeDelta = mQuarterCurrentAnimPlayTime * QUARTER_ROTATE / QUARTER_ANIM_DURATION;
if (mQuarterCurrentAnimStartIndex == QUARTER_ANIM_INDEX_1) {
mQuarterAnim4.setFloatValues(degreeDelta, QUARTER_FROM_1);
mQuarterAnim4.setDuration(mQuarterCurrentAnimPlayTime);
mAnimatorSet.play(mQuarterAnim4);
}
A full code snippet you can find here

Just put the view which you're going to animate it in place of viewToFlip.
ObjectAnimator flip = ObjectAnimator.ofFloat(viewToFlip, "rotationY", 0f, 360f); // or rotationX
flip.setDuration(2000); // 2 seconds
flip.start();

Adding to A. Steenbergen's great answer. When flipping the same view (updating a TextView for example) I removed the View.Visibility change in the constructor in order to keep the transition smoother.
public FlipListener(final View front, final View back) {
this.mFrontView = front;
this.mBackView = back;
}