samples/devbytes/graphics/FoldingLayout/src/com/example/android/foldinglayout/FoldingLayoutActivity.java - platform/development - Git at Google

 /*
  * Copyright (C) 2013 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.example.android.foldinglayout;

 import android.animation.ObjectAnimator;
 import android.animation.ValueAnimator;
 import android.app.Activity;
 import android.graphics.Color;
 import android.graphics.ColorMatrix;
 import android.graphics.ColorMatrixColorFilter;
 import android.graphics.Paint;
 import android.graphics.SurfaceTexture;
 import android.hardware.Camera;
 import android.os.Build;
 import android.os.Bundle;
 import android.view.GestureDetector;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.MotionEvent;
 import android.view.TextureView;
 import android.view.View;
 import android.view.ViewConfiguration;
 import android.view.ViewGroup;
 import android.view.animation.AccelerateInterpolator;
 import android.widget.AdapterView;
 import android.widget.AdapterView.OnItemSelectedListener;
 import android.widget.ImageView;
 import android.widget.SeekBar;
 import android.widget.Spinner;

 import com.example.android.foldinglayout.FoldingLayout.Orientation;

 import java.io.IOException;

 /**
  * This application creates  a paper like folding effect of some view.
  * The number of folds, orientation (vertical or horizontal) of the fold, and the
  * anchor point about which the view will fold can be set to achieve different
  * folding effects.
  *
  * Using bitmap and canvas scaling techniques, the foldingLayout can be scaled so as
  * to depict a paper-like folding effect. The addition of shadows on the separate folds
  * adds a sense of realism to the visual effect.
  *
  * This application shows folding of a TextureView containing a live camera feed,
  * as well as the folding of an ImageView with a static image. The TextureView experiences
  * jagged edges as a result of scaling operations on rectangles. The ImageView however
  * contains a 1 pixel transparent border around its contents which can be used to avoid
  * this unwanted artifact.
  */
 public class FoldingLayoutActivity extends Activity {

     private final int ANTIALIAS_PADDING = 1;

     private final int FOLD_ANIMATION_DURATION = 1000;

     /* A bug was introduced in Android 4.3 that ignores changes to the Canvas state
      * between multiple calls to super.dispatchDraw() when running with hardware acceleration.
      * To account for this bug, a slightly different approach was taken to fold a
      * static image whereby a bitmap of the original contents is captured and drawn
      * in segments onto the canvas. However, this method does not permit the folding
      * of a TextureView hosting a live camera feed which continuously updates.
      * Furthermore, the sepia effect was removed from the bitmap variation of the
      * demo to simplify the logic when running with this workaround."
      */
     static final boolean IS_JBMR2 = Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN_MR2;

     private FoldingLayout mFoldLayout;
     private SeekBar mAnchorSeekBar;
     private Orientation mOrientation = Orientation.HORIZONTAL;

     private int mTranslation = 0;
     private int mNumberOfFolds = 2;
     private int mParentPositionY = -1;
     private int mTouchSlop = -1;

     private float mAnchorFactor = 0;

     private boolean mDidLoadSpinner = true;
     private boolean mDidNotStartScroll = true;

     private boolean mIsCameraFeed = false;
     private boolean mIsSepiaOn = true;

     private GestureDetector mScrollGestureDetector;
     private ItemSelectedListener mItemSelectedListener;

     private Camera mCamera;
     private TextureView mTextureView;
     private ImageView mImageView;

     private Paint mSepiaPaint;
     private Paint mDefaultPaint;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);

         setContentView(R.layout.activity_fold);

         mImageView = (ImageView)findViewById(R.id.image_view);
         mImageView.setPadding(ANTIALIAS_PADDING, ANTIALIAS_PADDING, ANTIALIAS_PADDING,
                 ANTIALIAS_PADDING);
         mImageView.setScaleType(ImageView.ScaleType.FIT_XY);
         mImageView.setImageDrawable(getResources().getDrawable(R.drawable.image));

         mTextureView = new TextureView(this);
         mTextureView.setSurfaceTextureListener(mSurfaceTextureListener);

         mAnchorSeekBar = (SeekBar)findViewById(R.id.anchor_seek_bar);
         mFoldLayout = (FoldingLayout)findViewById(R.id.fold_view);
         mFoldLayout.setBackgroundColor(Color.BLACK);
         mFoldLayout.setFoldListener(mOnFoldListener);

         mTouchSlop = ViewConfiguration.get(this).getScaledTouchSlop();

         mAnchorSeekBar.setOnSeekBarChangeListener(mSeekBarChangeListener);

         mScrollGestureDetector = new GestureDetector(this, new ScrollGestureDetector());
         mItemSelectedListener = new ItemSelectedListener();

         mDefaultPaint = new Paint();
         mSepiaPaint = new Paint();

         ColorMatrix m1 = new ColorMatrix();
         ColorMatrix m2 = new ColorMatrix();
         m1.setSaturation(0);
         m2.setScale(1f, .95f, .82f, 1.0f);
         m1.setConcat(m2, m1);
         mSepiaPaint.setColorFilter(new ColorMatrixColorFilter(m1));
     }

     /**
      * This listener, along with the setSepiaLayer method below, show a possible use case
      * of the OnFoldListener provided with the FoldingLayout. This is a fun extra addition
      * to the demo showing what kind of visual effects can be applied to the child of the
      * FoldingLayout by setting the layer type to hardware. With a hardware layer type
      * applied to the child, a paint object can also be applied to the same layer. Using
      * the concatenation of two different color matrices (above), a color filter was created
      * which simulates a sepia effect on the layer.*/
     private OnFoldListener mOnFoldListener =
             new OnFoldListener() {
         @Override
         public void onStartFold() {
             if (mIsSepiaOn) {
                 setSepiaLayer(mFoldLayout.getChildAt(0), true);
             }
         }

         @Override
         public void onEndFold() {
             setSepiaLayer(mFoldLayout.getChildAt(0), false);
         }
     };

     private void setSepiaLayer (View view, boolean isSepiaLayerOn) {
         if (!IS_JBMR2) {
             if (isSepiaLayerOn) {
                 view.setLayerType(View.LAYER_TYPE_HARDWARE, null);
                 view.setLayerPaint(mSepiaPaint);
             } else {
                 view.setLayerPaint(mDefaultPaint);
             }
         }
     }

     /**
      * Creates a SurfaceTextureListener in order to prepare a TextureView
      * which displays a live, and continuously updated, feed from the Camera.
      */
     private TextureView.SurfaceTextureListener mSurfaceTextureListener = new TextureView
             .SurfaceTextureListener() {
         @Override
         public void onSurfaceTextureAvailable(SurfaceTexture surfaceTexture, int i, int i2) {
             mCamera = Camera.open();

             if (mCamera == null && Camera.getNumberOfCameras() > 1) {
                 mCamera = mCamera.open(Camera.CameraInfo.CAMERA_FACING_FRONT);
             }

             if (mCamera == null) {
                 return;
             }

             try {
                 mCamera.setPreviewTexture(surfaceTexture);
                 mCamera.setDisplayOrientation(90);
                 mCamera.startPreview();
             } catch (IOException e) {
                 e.printStackTrace();
             }
         }

         @Override
         public void onSurfaceTextureSizeChanged(SurfaceTexture surfaceTexture, int i, int i2) {
             // Ignored, Camera does all the work for us
         }

         @Override
         public boolean onSurfaceTextureDestroyed(SurfaceTexture surfaceTexture) {
             if (mCamera != null) {
                 mCamera.stopPreview();
                 mCamera.release();
             }
             return true;
         }

         @Override
         public void onSurfaceTextureUpdated(SurfaceTexture surfaceTexture) {
             // Invoked every time there's a new Camera preview frame
         }
     };

     /**
      * A listener for scrolling changes in the seekbar. The anchor point of the folding
      * view is updated every time the seekbar stops tracking touch events. Every time the
      * anchor point is updated, the folding view is restored to a default unfolded state.
      */
     private SeekBar.OnSeekBarChangeListener mSeekBarChangeListener = new SeekBar
             .OnSeekBarChangeListener() {
         @Override
         public void onProgressChanged(SeekBar seekBar, int i, boolean b) {
         }

         @Override
         public void onStartTrackingTouch(SeekBar seekBar) {
         }

         @Override
         public void onStopTrackingTouch(SeekBar seekBar) {
             mTranslation = 0;
             mAnchorFactor = ((float)mAnchorSeekBar.getProgress())/100.0f;
             mFoldLayout.setAnchorFactor(mAnchorFactor);
         }
     };

     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         if (IS_JBMR2) {
             getMenuInflater().inflate(R.menu.fold_with_bug, menu);
         } else {
             getMenuInflater().inflate(R.menu.fold, menu);
         }
         Spinner s = (Spinner) menu.findItem(R.id.num_of_folds).getActionView();
         s.setOnItemSelectedListener(mItemSelectedListener);
         return true;
     }

     @Override
     public void onWindowFocusChanged (boolean hasFocus) {
         super.onWindowFocusChanged(hasFocus);

         int[] loc = new int[2];
         mFoldLayout.getLocationOnScreen(loc);
         mParentPositionY = loc[1];
     }

     @Override
     public boolean onTouchEvent(MotionEvent me) {
         return mScrollGestureDetector.onTouchEvent(me);
     }

     @Override
     public boolean onOptionsItemSelected (MenuItem item) {
         switch(item.getItemId()) {
             case R.id.animate_fold:
                 animateFold();
                 break;
             case R.id.toggle_orientation:
                 mOrientation = (mOrientation == Orientation.HORIZONTAL) ? Orientation.VERTICAL :
                         Orientation.HORIZONTAL;
                 item.setTitle((mOrientation == Orientation.HORIZONTAL) ? R.string.vertical :
                 R.string.horizontal);
                 mTranslation = 0;
                 mFoldLayout.setOrientation(mOrientation);
                 break;
             case R.id.camera_feed:
                 mIsCameraFeed = !mIsCameraFeed;
                 item.setTitle(mIsCameraFeed ? R.string.static_image : R.string.camera_feed);
                 item.setChecked(mIsCameraFeed);
                 if (mIsCameraFeed) {
                     mFoldLayout.removeView(mImageView);
                     mFoldLayout.addView(mTextureView, new ViewGroup.LayoutParams(
                             mFoldLayout.getWidth(), mFoldLayout.getHeight()));
                 } else {
                     mFoldLayout.removeView(mTextureView);
                     mFoldLayout.addView(mImageView, new ViewGroup.LayoutParams(
                             mFoldLayout.getWidth(), mFoldLayout.getHeight()));
                 }
                 mTranslation = 0;
                 break;
             case R.id.sepia:
                 mIsSepiaOn = !mIsSepiaOn;
                 item.setChecked(!mIsSepiaOn);
                 if (mIsSepiaOn && mFoldLayout.getFoldFactor() != 0) {
                     setSepiaLayer(mFoldLayout.getChildAt(0), true);
                 } else {
                     setSepiaLayer(mFoldLayout.getChildAt(0), false);
                 }
                 break;
             default:
                break;

         }
         return super.onOptionsItemSelected(item);
     }

     /**
      * Animates the folding view inwards (to a completely folded state) from its
      * current state and then back out to its original state.
      */
     public void animateFold ()
     {
         float foldFactor = mFoldLayout.getFoldFactor();

         ObjectAnimator animator = ObjectAnimator.ofFloat(mFoldLayout, "foldFactor", foldFactor, 1);
         animator.setRepeatMode(ValueAnimator.REVERSE);
         animator.setRepeatCount(1);
         animator.setDuration(FOLD_ANIMATION_DURATION);
         animator.setInterpolator(new AccelerateInterpolator());
         animator.start();
     }

     /**
      * Listens for selection events of the spinner located on the action bar. Every
      * time a new value is selected, the number of folds in the folding view is updated
      * and is also restored to a default unfolded state.
      */
     private class ItemSelectedListener implements OnItemSelectedListener {
         @Override
         public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
             mNumberOfFolds = Integer.parseInt(parent.getItemAtPosition(pos).toString());
             if (mDidLoadSpinner) {
                 mDidLoadSpinner = false;
             } else {
                 mTranslation = 0;
                 mFoldLayout.setNumberOfFolds(mNumberOfFolds);
             }
         }

         @Override
         public void onNothingSelected(AdapterView<?> arg0) {
         }
     }

     /** This class uses user touch events to fold and unfold the folding view. */
     private class ScrollGestureDetector extends GestureDetector.SimpleOnGestureListener {
         @Override
         public boolean onDown (MotionEvent e) {
             mDidNotStartScroll = true;
             return true;
         }

         /**
          * All the logic here is used to determine by what factor the paper view should
          * be folded in response to the user's touch events. The logic here uses vertical
          * scrolling to fold a vertically oriented view and horizontal scrolling to fold
          * a horizontally oriented fold. Depending on where the anchor point of the fold is,
          * movements towards or away from the anchor point will either fold or unfold
          * the paper respectively.
          *
          * The translation logic here also accounts for the touch slop when a new user touch
          * begins, but before a scroll event is first invoked.
          */
         @Override
         public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
             int touchSlop = 0;
             float factor;
             if (mOrientation == Orientation.VERTICAL) {
                 factor = Math.abs((float)(mTranslation) / (float)(mFoldLayout.getHeight()));

                 if (e2.getY() - mParentPositionY <= mFoldLayout.getHeight()
                         && e2.getY() - mParentPositionY >= 0) {
                     if ((e2.getY() - mParentPositionY) > mFoldLayout.getHeight() * mAnchorFactor) {
                         mTranslation -= (int)distanceY;
                         touchSlop = distanceY < 0 ? -mTouchSlop : mTouchSlop;
                     } else {
                         mTranslation += (int)distanceY;
                         touchSlop = distanceY < 0 ? mTouchSlop : -mTouchSlop;
                     }
                     mTranslation = mDidNotStartScroll ? mTranslation + touchSlop : mTranslation;

                     if (mTranslation < -mFoldLayout.getHeight()) {
                         mTranslation = -mFoldLayout.getHeight();
                     }
                 }
             } else {
                 factor = Math.abs(((float)mTranslation) / ((float) mFoldLayout.getWidth()));

                 if (e2.getRawX() > mFoldLayout.getWidth() * mAnchorFactor) {
                     mTranslation -= (int)distanceX;
                     touchSlop = distanceX < 0 ? -mTouchSlop : mTouchSlop;
                 } else {
                     mTranslation += (int)distanceX;
                     touchSlop = distanceX < 0 ? mTouchSlop : -mTouchSlop;
                 }
                 mTranslation = mDidNotStartScroll ? mTranslation + touchSlop : mTranslation;

                 if (mTranslation < -mFoldLayout.getWidth()) {
                     mTranslation = -mFoldLayout.getWidth();
                 }
             }

             mDidNotStartScroll = false;

             if (mTranslation > 0) {
                 mTranslation = 0;
             }

             mFoldLayout.setFoldFactor(factor);

             return true;
         }
     }
 }
	/*
	* Copyright (C) 2013 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.example.android.foldinglayout;

	import android.animation.ObjectAnimator;
	import android.animation.ValueAnimator;
	import android.app.Activity;
	import android.graphics.Color;
	import android.graphics.ColorMatrix;
	import android.graphics.ColorMatrixColorFilter;
	import android.graphics.Paint;
	import android.graphics.SurfaceTexture;
	import android.hardware.Camera;
	import android.os.Build;
	import android.os.Bundle;
	import android.view.GestureDetector;
	import android.view.Menu;
	import android.view.MenuItem;
	import android.view.MotionEvent;
	import android.view.TextureView;
	import android.view.View;
	import android.view.ViewConfiguration;
	import android.view.ViewGroup;
	import android.view.animation.AccelerateInterpolator;
	import android.widget.AdapterView;
	import android.widget.AdapterView.OnItemSelectedListener;
	import android.widget.ImageView;
	import android.widget.SeekBar;
	import android.widget.Spinner;

	import com.example.android.foldinglayout.FoldingLayout.Orientation;

	import java.io.IOException;

	/**
	* This application creates a paper like folding effect of some view.
	* The number of folds, orientation (vertical or horizontal) of the fold, and the
	* anchor point about which the view will fold can be set to achieve different
	* folding effects.
	*
	* Using bitmap and canvas scaling techniques, the foldingLayout can be scaled so as
	* to depict a paper-like folding effect. The addition of shadows on the separate folds
	* adds a sense of realism to the visual effect.
	*
	* This application shows folding of a TextureView containing a live camera feed,
	* as well as the folding of an ImageView with a static image. The TextureView experiences
	* jagged edges as a result of scaling operations on rectangles. The ImageView however
	* contains a 1 pixel transparent border around its contents which can be used to avoid
	* this unwanted artifact.
	*/
	public class FoldingLayoutActivity extends Activity {

	private final int ANTIALIAS_PADDING = 1;

	private final int FOLD_ANIMATION_DURATION = 1000;

	/* A bug was introduced in Android 4.3 that ignores changes to the Canvas state
	* between multiple calls to super.dispatchDraw() when running with hardware acceleration.
	* To account for this bug, a slightly different approach was taken to fold a
	* static image whereby a bitmap of the original contents is captured and drawn
	* in segments onto the canvas. However, this method does not permit the folding
	* of a TextureView hosting a live camera feed which continuously updates.
	* Furthermore, the sepia effect was removed from the bitmap variation of the
	* demo to simplify the logic when running with this workaround."
	*/
	static final boolean IS_JBMR2 = Build.VERSION.SDK_INT == Build.VERSION_CODES.JELLY_BEAN_MR2;

	private FoldingLayout mFoldLayout;
	private SeekBar mAnchorSeekBar;
	private Orientation mOrientation = Orientation.HORIZONTAL;

	private int mTranslation = 0;
	private int mNumberOfFolds = 2;
	private int mParentPositionY = -1;
	private int mTouchSlop = -1;

	private float mAnchorFactor = 0;

	private boolean mDidLoadSpinner = true;
	private boolean mDidNotStartScroll = true;

	private boolean mIsCameraFeed = false;
	private boolean mIsSepiaOn = true;

	private GestureDetector mScrollGestureDetector;
	private ItemSelectedListener mItemSelectedListener;

	private Camera mCamera;
	private TextureView mTextureView;
	private ImageView mImageView;

	private Paint mSepiaPaint;
	private Paint mDefaultPaint;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);

	setContentView(R.layout.activity_fold);

	mImageView = (ImageView)findViewById(R.id.image_view);
	mImageView.setPadding(ANTIALIAS_PADDING, ANTIALIAS_PADDING, ANTIALIAS_PADDING,
	ANTIALIAS_PADDING);
	mImageView.setScaleType(ImageView.ScaleType.FIT_XY);
	mImageView.setImageDrawable(getResources().getDrawable(R.drawable.image));

	mTextureView = new TextureView(this);
	mTextureView.setSurfaceTextureListener(mSurfaceTextureListener);

	mAnchorSeekBar = (SeekBar)findViewById(R.id.anchor_seek_bar);
	mFoldLayout = (FoldingLayout)findViewById(R.id.fold_view);
	mFoldLayout.setBackgroundColor(Color.BLACK);
	mFoldLayout.setFoldListener(mOnFoldListener);

	mTouchSlop = ViewConfiguration.get(this).getScaledTouchSlop();

	mAnchorSeekBar.setOnSeekBarChangeListener(mSeekBarChangeListener);

	mScrollGestureDetector = new GestureDetector(this, new ScrollGestureDetector());
	mItemSelectedListener = new ItemSelectedListener();

	mDefaultPaint = new Paint();
	mSepiaPaint = new Paint();

	ColorMatrix m1 = new ColorMatrix();
	ColorMatrix m2 = new ColorMatrix();
	m1.setSaturation(0);
	m2.setScale(1f, .95f, .82f, 1.0f);
	m1.setConcat(m2, m1);
	mSepiaPaint.setColorFilter(new ColorMatrixColorFilter(m1));
	}

	/**
	* This listener, along with the setSepiaLayer method below, show a possible use case
	* of the OnFoldListener provided with the FoldingLayout. This is a fun extra addition
	* to the demo showing what kind of visual effects can be applied to the child of the
	* FoldingLayout by setting the layer type to hardware. With a hardware layer type
	* applied to the child, a paint object can also be applied to the same layer. Using
	* the concatenation of two different color matrices (above), a color filter was created
	* which simulates a sepia effect on the layer.*/
	private OnFoldListener mOnFoldListener =
	new OnFoldListener() {
	@Override
	public void onStartFold() {
	if (mIsSepiaOn) {
	setSepiaLayer(mFoldLayout.getChildAt(0), true);
	}
	}

	@Override
	public void onEndFold() {
	setSepiaLayer(mFoldLayout.getChildAt(0), false);
	}
	};

	private void setSepiaLayer (View view, boolean isSepiaLayerOn) {
	if (!IS_JBMR2) {
	if (isSepiaLayerOn) {
	view.setLayerType(View.LAYER_TYPE_HARDWARE, null);
	view.setLayerPaint(mSepiaPaint);
	} else {
	view.setLayerPaint(mDefaultPaint);
	}
	}
	}

	/**
	* Creates a SurfaceTextureListener in order to prepare a TextureView
	* which displays a live, and continuously updated, feed from the Camera.
	*/
	private TextureView.SurfaceTextureListener mSurfaceTextureListener = new TextureView
	.SurfaceTextureListener() {
	@Override
	public void onSurfaceTextureAvailable(SurfaceTexture surfaceTexture, int i, int i2) {
	mCamera = Camera.open();

	if (mCamera == null && Camera.getNumberOfCameras() > 1) {
	mCamera = mCamera.open(Camera.CameraInfo.CAMERA_FACING_FRONT);
	}

	if (mCamera == null) {
	return;
	}

	try {
	mCamera.setPreviewTexture(surfaceTexture);
	mCamera.setDisplayOrientation(90);
	mCamera.startPreview();
	} catch (IOException e) {
	e.printStackTrace();
	}
	}

	@Override
	public void onSurfaceTextureSizeChanged(SurfaceTexture surfaceTexture, int i, int i2) {
	// Ignored, Camera does all the work for us
	}

	@Override
	public boolean onSurfaceTextureDestroyed(SurfaceTexture surfaceTexture) {
	if (mCamera != null) {
	mCamera.stopPreview();
	mCamera.release();
	}
	return true;
	}

	@Override
	public void onSurfaceTextureUpdated(SurfaceTexture surfaceTexture) {
	// Invoked every time there's a new Camera preview frame
	}
	};

	/**
	* A listener for scrolling changes in the seekbar. The anchor point of the folding
	* view is updated every time the seekbar stops tracking touch events. Every time the
	* anchor point is updated, the folding view is restored to a default unfolded state.
	*/
	private SeekBar.OnSeekBarChangeListener mSeekBarChangeListener = new SeekBar
	.OnSeekBarChangeListener() {
	@Override
	public void onProgressChanged(SeekBar seekBar, int i, boolean b) {
	}

	@Override
	public void onStartTrackingTouch(SeekBar seekBar) {
	}

	@Override
	public void onStopTrackingTouch(SeekBar seekBar) {
	mTranslation = 0;
	mAnchorFactor = ((float)mAnchorSeekBar.getProgress())/100.0f;
	mFoldLayout.setAnchorFactor(mAnchorFactor);
	}
	};

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
	if (IS_JBMR2) {
	getMenuInflater().inflate(R.menu.fold_with_bug, menu);
	} else {
	getMenuInflater().inflate(R.menu.fold, menu);
	}
	Spinner s = (Spinner) menu.findItem(R.id.num_of_folds).getActionView();
	s.setOnItemSelectedListener(mItemSelectedListener);
	return true;
	}

	@Override
	public void onWindowFocusChanged (boolean hasFocus) {
	super.onWindowFocusChanged(hasFocus);

	int[] loc = new int[2];
	mFoldLayout.getLocationOnScreen(loc);
	mParentPositionY = loc[1];
	}

	@Override
	public boolean onTouchEvent(MotionEvent me) {
	return mScrollGestureDetector.onTouchEvent(me);
	}

	@Override
	public boolean onOptionsItemSelected (MenuItem item) {
	switch(item.getItemId()) {
	case R.id.animate_fold:
	animateFold();
	break;
	case R.id.toggle_orientation:
	mOrientation = (mOrientation == Orientation.HORIZONTAL) ? Orientation.VERTICAL :
	Orientation.HORIZONTAL;
	item.setTitle((mOrientation == Orientation.HORIZONTAL) ? R.string.vertical :
	R.string.horizontal);
	mTranslation = 0;
	mFoldLayout.setOrientation(mOrientation);
	break;
	case R.id.camera_feed:
	mIsCameraFeed = !mIsCameraFeed;
	item.setTitle(mIsCameraFeed ? R.string.static_image : R.string.camera_feed);
	item.setChecked(mIsCameraFeed);
	if (mIsCameraFeed) {
	mFoldLayout.removeView(mImageView);
	mFoldLayout.addView(mTextureView, new ViewGroup.LayoutParams(
	mFoldLayout.getWidth(), mFoldLayout.getHeight()));
	} else {
	mFoldLayout.removeView(mTextureView);
	mFoldLayout.addView(mImageView, new ViewGroup.LayoutParams(
	mFoldLayout.getWidth(), mFoldLayout.getHeight()));
	}
	mTranslation = 0;
	break;
	case R.id.sepia:
	mIsSepiaOn = !mIsSepiaOn;
	item.setChecked(!mIsSepiaOn);
	if (mIsSepiaOn && mFoldLayout.getFoldFactor() != 0) {
	setSepiaLayer(mFoldLayout.getChildAt(0), true);
	} else {
	setSepiaLayer(mFoldLayout.getChildAt(0), false);
	}
	break;
	default:
	break;

	}
	return super.onOptionsItemSelected(item);
	}

	/**
	* Animates the folding view inwards (to a completely folded state) from its
	* current state and then back out to its original state.
	*/
	public void animateFold ()
	{
	float foldFactor = mFoldLayout.getFoldFactor();

	ObjectAnimator animator = ObjectAnimator.ofFloat(mFoldLayout, "foldFactor", foldFactor, 1);
	animator.setRepeatMode(ValueAnimator.REVERSE);
	animator.setRepeatCount(1);
	animator.setDuration(FOLD_ANIMATION_DURATION);
	animator.setInterpolator(new AccelerateInterpolator());
	animator.start();
	}

	/**
	* Listens for selection events of the spinner located on the action bar. Every
	* time a new value is selected, the number of folds in the folding view is updated
	* and is also restored to a default unfolded state.
	*/
	private class ItemSelectedListener implements OnItemSelectedListener {
	@Override
	public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
	mNumberOfFolds = Integer.parseInt(parent.getItemAtPosition(pos).toString());
	if (mDidLoadSpinner) {
	mDidLoadSpinner = false;
	} else {
	mTranslation = 0;
	mFoldLayout.setNumberOfFolds(mNumberOfFolds);
	}
	}

	@Override
	public void onNothingSelected(AdapterView<?> arg0) {
	}
	}

	/** This class uses user touch events to fold and unfold the folding view. */
	private class ScrollGestureDetector extends GestureDetector.SimpleOnGestureListener {
	@Override
	public boolean onDown (MotionEvent e) {
	mDidNotStartScroll = true;
	return true;
	}

	/**
	* All the logic here is used to determine by what factor the paper view should
	* be folded in response to the user's touch events. The logic here uses vertical
	* scrolling to fold a vertically oriented view and horizontal scrolling to fold
	* a horizontally oriented fold. Depending on where the anchor point of the fold is,
	* movements towards or away from the anchor point will either fold or unfold
	* the paper respectively.
	*
	* The translation logic here also accounts for the touch slop when a new user touch
	* begins, but before a scroll event is first invoked.
	*/
	@Override
	public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
	int touchSlop = 0;
	float factor;
	if (mOrientation == Orientation.VERTICAL) {
	factor = Math.abs((float)(mTranslation) / (float)(mFoldLayout.getHeight()));

	if (e2.getY() - mParentPositionY <= mFoldLayout.getHeight()
	&& e2.getY() - mParentPositionY >= 0) {
	if ((e2.getY() - mParentPositionY) > mFoldLayout.getHeight() * mAnchorFactor) {
	mTranslation -= (int)distanceY;
	touchSlop = distanceY < 0 ? -mTouchSlop : mTouchSlop;
	} else {
	mTranslation += (int)distanceY;
	touchSlop = distanceY < 0 ? mTouchSlop : -mTouchSlop;
	}
	mTranslation = mDidNotStartScroll ? mTranslation + touchSlop : mTranslation;

	if (mTranslation < -mFoldLayout.getHeight()) {
	mTranslation = -mFoldLayout.getHeight();
	}
	}
	} else {
	factor = Math.abs(((float)mTranslation) / ((float) mFoldLayout.getWidth()));

	if (e2.getRawX() > mFoldLayout.getWidth() * mAnchorFactor) {
	mTranslation -= (int)distanceX;
	touchSlop = distanceX < 0 ? -mTouchSlop : mTouchSlop;
	} else {
	mTranslation += (int)distanceX;
	touchSlop = distanceX < 0 ? mTouchSlop : -mTouchSlop;
	}
	mTranslation = mDidNotStartScroll ? mTranslation + touchSlop : mTranslation;

	if (mTranslation < -mFoldLayout.getWidth()) {
	mTranslation = -mFoldLayout.getWidth();
	}
	}

	mDidNotStartScroll = false;

	if (mTranslation > 0) {
	mTranslation = 0;
	}

	mFoldLayout.setFoldFactor(factor);

	return true;
	}
	}
	}