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package com.facebook.rebound.origami;
import android.content.res.Resources;
import android.os.Bundle;
import android.view.View;
import android.view.ViewTreeObserver;
import com.facebook.rebound.SimpleSpringListener;
import com.facebook.rebound.Spring;
import com.facebook.rebound.SpringConfig;
import com.facebook.rebound.SpringConfigRegistry;
import com.facebook.rebound.SpringSystem;
import com.facebook.rebound.SpringUtil;
import com.facebook.rebound.ui.SpringConfiguratorView;
import com.facebook.rebound.ui.Util;
* This Activity demonstrates a simple example of creating a spring toggle based animation as shown
* in the Origami examples
public class OrigamiActivity extends Activity {
// Create a spring configuration based on Origami values from the Photo Grid example.
private static final SpringConfig ORIGAMI_SPRING_CONFIG = SpringConfig.fromOrigamiTensionAndFriction(40, 7);
private Spring mSpring;
private View mSelectedPhoto;
private View mPhotoGrid;
private View mFeedbackBar;
private SpringConfiguratorView mSpringConfiguratorView;
protected void onCreate(Bundle savedInstanceState) {
// Get references to our views.
mPhotoGrid = findViewById(;
mSelectedPhoto = findViewById(;
mFeedbackBar = findViewById(;
mSpringConfiguratorView = (SpringConfiguratorView) findViewById(;
// Setup the Spring by creating a SpringSystem adding a SimpleListener that renders the
// animation whenever the spring is updated.
mSpring = SpringSystem
.addListener(new SimpleSpringListener() {
public void onSpringUpdate(Spring spring) {
// Just tell the UI to update based on the springs current state.
// Here we just wait until the first layout pass finishes and call our render method to update
// the animation to the initial resting state of the spring.
new ViewTreeObserver.OnGlobalLayoutListener() {
public void onGlobalLayout() {
/** Optional - Live Spring Tuning **/
// Put our config into a registry. This is optional, but it gives you the ability to live tune
// the spring using the SpringConfiguratorView which will show up at the bottom of the screen.
SpringConfigRegistry.getInstance().addSpringConfig(ORIGAMI_SPRING_CONFIG, "origami animation spring");
// Tell the SpringConfiguratorView that we've updated the registry to allow you to live tune the animation spring.
// Uncomment this line to actually show the SpringConfiguratorView allowing you to live tune
// the Spring constants as you manipulate the UI.
* On click we just move the springs end state from 0 to 1. This allows the Spring to act much
* like an Origami switch.
public void handleClick(View view) {
if (mSpring.getEndValue() == 0) {
} else {
* This method takes the current state of the spring and maps it to all the values for each UI
* element that is animated on this spring. This allows the Spring to act as a common timing
* function for the animation ensuring that all element transitions are synchronized.
* You can think of these mappings as similiar to Origami transitions.
* SpringUtil#mapValueFromRangeToRange converts the spring's 0 to 1 transition and maps it to the
* range of animation for a property on a view such as translation, scale, rotation, and alpha.
private void render() {
Resources resources = getResources();
// Get the current spring value.
double value = mSpring.getCurrentValue();
// Map the spring to the feedback bar position so that its hidden off screen and bounces in on tap.
float barPosition =
(float) SpringUtil.mapValueFromRangeToRange(value, 0, 1, mFeedbackBar.getHeight(), 0);
// Map the spring to the selected photo scale as it moves into and out of the grid.
float selectedPhotoScale =
(float) SpringUtil.mapValueFromRangeToRange(value, 0, 1, 0.33, 1);
selectedPhotoScale = Math.max(selectedPhotoScale, 0); // Clamp the value so we don't go below 0.
// Map the spring to the selected photo translation from its position in the grid
float selectedPhotoTranslateX = (float) SpringUtil.mapValueFromRangeToRange(value, 0, 1, Util.dpToPx(-106.667f, resources), 0);
float selectedPhotoTranslateY = (float) SpringUtil.mapValueFromRangeToRange(value, 0, 1, Util.dpToPx(46.667f, resources), 0);
// Map the spring to the photo grid alpha as it fades to black when the photo is selected.
float gridAlpha =
(float) SpringUtil.mapValueFromRangeToRange(value, 0, 1, 1, 0);
// Map the spring to the photo grid scale so that it scales down slightly as the selected photo // zooms in.
float gridScale =
(float) SpringUtil.mapValueFromRangeToRange(value, 0, 1, 1, 0.95);
gridScale = Math.max(gridScale, 0); // Clamp the value so we don't go below 0.

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@tylerchesley tylerchesley commented Jul 15, 2015

Do you have an example layout file?

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