/*******************************************************************************
* Copyright 2011, 2012 Chris Banes.
*
* 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 uk.co.senab.photoview;
import static android.view.MotionEvent.ACTION_CANCEL;
import static android.view.MotionEvent.ACTION_DOWN;
import static android.view.MotionEvent.ACTION_UP;
import java.lang.ref.WeakReference;
import uk.co.senab.photoview.gestures.OnGestureListener;
import uk.co.senab.photoview.gestures.VersionedGestureDetector;
import uk.co.senab.photoview.scrollerproxy.ScrollerProxy;
import android.content.Context;
import android.graphics.Matrix;
import android.graphics.Matrix.ScaleToFit;
import android.graphics.RectF;
import android.graphics.drawable.Drawable;
import android.util.FloatMath;
import android.util.Log;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnLongClickListener;
import android.view.ViewParent;
import android.view.ViewTreeObserver;
import android.view.animation.AccelerateDecelerateInterpolator;
import android.view.animation.Interpolator;
import android.widget.ImageView;
import android.widget.ImageView.ScaleType;
public class PhotoViewAttacher implements IPhotoView, View.OnTouchListener,
OnGestureListener, android.view.GestureDetector.OnDoubleTapListener,
ViewTreeObserver.OnGlobalLayoutListener {
private static final String LOG_TAG = "PhotoViewAttacher";
// let debug flag be dynamic, but still Proguard can be used to remove from
// release builds
private static final boolean DEBUG = Log.isLoggable(LOG_TAG, Log.DEBUG);
static final Interpolator sInterpolator = new AccelerateDecelerateInterpolator();
static final int ZOOM_DURATION = 200;
static final int EDGE_NONE = -1;
static final int EDGE_LEFT = 0;
static final int EDGE_RIGHT = 1;
static final int EDGE_BOTH = 2;
public static final float DEFAULT_MAX_SCALE = 3.0f;
public static final float DEFAULT_MID_SCALE = 1.75f;
public static final float DEFAULT_MIN_SCALE = 1.0f;
private float mMinScale = DEFAULT_MIN_SCALE;
private float mMidScale = DEFAULT_MID_SCALE;
private float mMaxScale = DEFAULT_MAX_SCALE;
private boolean mAllowParentInterceptOnEdge = true;
private static void checkZoomLevels(float minZoom, float midZoom,
float maxZoom) {
if (minZoom >= midZoom) {
throw new IllegalArgumentException(
"MinZoom has to be less than MidZoom");
} else if (midZoom >= maxZoom) {
throw new IllegalArgumentException(
"MidZoom has to be less than MaxZoom");
}
}
/**
* @return true if the ImageView exists, and it's Drawable existss
*/
private static boolean hasDrawable(ImageView imageView) {
return null != imageView && null != imageView.getDrawable();
}
/**
* @return true if the ScaleType is supported.
*/
private static boolean isSupportedScaleType(final ScaleType scaleType) {
if (null == scaleType) {
return false;
}
switch (scaleType) {
case MATRIX:
throw new IllegalArgumentException(scaleType.name()
+ " is not supported in PhotoView");
default:
return true;
}
}
/**
* Set's the ImageView's ScaleType to Matrix.
*/
private static void setImageViewScaleTypeMatrix(ImageView imageView) {
/**
* PhotoView sets it's own ScaleType to Matrix, then diverts all calls
* setScaleType to this.setScaleType automatically.
*/
if (null != imageView && !(imageView instanceof PhotoView)) {
if (!ScaleType.MATRIX.equals(imageView.getScaleType())) {
imageView.setScaleType(ScaleType.MATRIX);
}
}
}
private WeakReference<ImageView> mImageView;
// Gesture Detectors
private GestureDetector mGestureDetector;
private uk.co.senab.photoview.gestures.GestureDetector mScaleDragDetector;
// These are set so we don't keep allocating them on the heap
private final Matrix mBaseMatrix = new Matrix();
private final Matrix mDrawMatrix = new Matrix();
private final Matrix mSuppMatrix = new Matrix();
private final RectF mDisplayRect = new RectF();
private final float[] mMatrixValues = new float[9];
// Listeners
private OnMatrixChangedListener mMatrixChangeListener;
private OnPhotoTapListener mPhotoTapListener;
private OnViewTapListener mViewTapListener;
private OnLongClickListener mLongClickListener;
private int mIvTop, mIvRight, mIvBottom, mIvLeft;
private FlingRunnable mCurrentFlingRunnable;
private int mScrollEdge = EDGE_BOTH;
private boolean mZoomEnabled;
private ScaleType mScaleType = ScaleType.FIT_CENTER;
public PhotoViewAttacher(ImageView imageView) {
mImageView = new WeakReference<ImageView>(imageView);
imageView.setOnTouchListener(this);
ViewTreeObserver observer = imageView.getViewTreeObserver();
if (null != observer)
observer.addOnGlobalLayoutListener(this);
// Make sure we using MATRIX Scale Type
setImageViewScaleTypeMatrix(imageView);
if (imageView.isInEditMode()) {
return;
}
// Create Gesture Detectors...
mScaleDragDetector = VersionedGestureDetector.newInstance(
imageView.getContext(), this);
mGestureDetector = new GestureDetector(imageView.getContext(),
new GestureDetector.SimpleOnGestureListener() {
// forward long click listener
@Override
public void onLongPress(MotionEvent e) {
if (null != mLongClickListener) {
mLongClickListener.onLongClick(getImageView());
}
}
});
mGestureDetector.setOnDoubleTapListener(this);
// Finally, update the UI so that we're zoomable
setZoomable(true);
}
@Override
public final boolean canZoom() {
return mZoomEnabled;
}
/**
* Clean-up the resources attached to this object. This needs to be called
* when the ImageView is no longer used. A good example is from
* {@link android.view.View#onDetachedFromWindow()} or from
* {@link android.app.Activity#onDestroy()}. This is automatically called if
* you are using {@link uk.co.senab.photoview.PhotoView}.
*/
@SuppressWarnings("deprecation")
public final void cleanup() {
if (null == mImageView) {
return; // cleanup already done
}
final ImageView imageView = mImageView.get();
if (null != imageView) {
// Remove this as a global layout listener
ViewTreeObserver observer = imageView.getViewTreeObserver();
if (null != observer && observer.isAlive()) {
observer.removeGlobalOnLayoutListener(this);
}
// Remove the ImageView's reference to this
imageView.setOnTouchListener(null);
// make sure a pending fling runnable won't be run
cancelFling();
}
if (null != mGestureDetector) {
mGestureDetector.setOnDoubleTapListener(null);
}
// Clear listeners too
mMatrixChangeListener = null;
mPhotoTapListener = null;
mViewTapListener = null;
// Finally, clear ImageView
mImageView = null;
}
@Override
public final RectF getDisplayRect() {
checkMatrixBounds();
return getDisplayRect(getDrawMatrix());
}
@Override
public boolean setDisplayMatrix(Matrix finalMatrix) {
if (finalMatrix == null)
throw new IllegalArgumentException("Matrix cannot be null");
ImageView imageView = getImageView();
if (null == imageView)
return false;
if (null == imageView.getDrawable())
return false;
mSuppMatrix.set(finalMatrix);
setImageViewMatrix(getDrawMatrix());
checkMatrixBounds();
return true;
}
private float mLastRotation = 0;
@Override
public void setPhotoViewRotation(float degrees) {
degrees %= 360;
mSuppMatrix.postRotate(mLastRotation - degrees);
mLastRotation = degrees;
checkAndDisplayMatrix();
}
public final ImageView getImageView() {
ImageView imageView = null;
if (null != mImageView) {
imageView = mImageView.get();
}
// If we don't have an ImageView, call cleanup()
if (null == imageView) {
cleanup();
Log.i(LOG_TAG,
"ImageView no longer exists. You should not use this PhotoViewAttacher any more.");
}
return imageView;
}
@Override
@Deprecated
public float getMinScale() {
return getMinimumScale();
}
@Override
public float getMinimumScale() {
return mMinScale;
}
@Override
@Deprecated
public float getMidScale() {
return getMediumScale();
}
@Override
public float getMediumScale() {
return mMidScale;
}
@Override
@Deprecated
public float getMaxScale() {
return getMaximumScale();
}
@Override
public float getMaximumScale() {
return mMaxScale;
}
@Override
public final float getScale() {
return FloatMath.sqrt((float) Math.pow(
getValue(mSuppMatrix, Matrix.MSCALE_X), 2)
+ (float) Math.pow(getValue(mSuppMatrix, Matrix.MSKEW_Y), 2));
}
@Override
public final ScaleType getScaleType() {
return mScaleType;
}
@Override
public final boolean onDoubleTap(MotionEvent ev) {
try {
float scale = getScale();
float x = ev.getX();
float y = ev.getY();
if (scale < mMidScale) {
setScale(mMidScale, x, y, true);
} else if (scale >= mMidScale && scale < mMaxScale) {
setScale(mMaxScale, x, y, true);
} else {
setScale(mMinScale, x, y, true);
}
} catch (ArrayIndexOutOfBoundsException e) {
// Can sometimes happen when getX() and getY() is called
}
return true;
}
@Override
public final boolean onDoubleTapEvent(MotionEvent e) {
// Wait for the confirmed onDoubleTap() instead
return false;
}
public final void onDrag(float dx, float dy) {
ImageView imageView = getImageView();
mSuppMatrix.postTranslate(dx, dy);
checkAndDisplayMatrix();
/**
* Here we decide whether to let the ImageView's parent to start taking
* over the touch event.
*
* First we check whether this function is enabled. We never want the
* parent to take over if we're scaling. We then check the edge we're
* on, and the direction of the scroll (i.e. if we're pulling against
* the edge, aka 'overscrolling', let the parent take over).
*/
if (mAllowParentInterceptOnEdge && !mScaleDragDetector.isScaling()) {
if (mScrollEdge == EDGE_BOTH
|| (mScrollEdge == EDGE_LEFT && dx >= 1f)
|| (mScrollEdge == EDGE_RIGHT && dx <= -1f)) {
ViewParent parent = imageView.getParent();
if (null != parent)
parent.requestDisallowInterceptTouchEvent(false);
}
}
}
public final void onFling(float startX, float startY, float velocityX,
float velocityY) {
ImageView imageView = getImageView();
mCurrentFlingRunnable = new FlingRunnable(imageView.getContext());
mCurrentFlingRunnable
.fling(getImageViewWidth(imageView),
getImageViewHeight(imageView), (int) velocityX,
(int) velocityY);
imageView.post(mCurrentFlingRunnable);
}
@Override
public final void onGlobalLayout() {
ImageView imageView = getImageView();
if (null != imageView && mZoomEnabled) {
final int top = imageView.getTop();
final int right = imageView.getRight();
final int bottom = imageView.getBottom();
final int left = imageView.getLeft();
/**
* We need to check whether the ImageView's bounds have changed.
* This would be easier if we targeted API 11+ as we could just use
* View.OnLayoutChangeListener. Instead we have to replicate the
* work, keeping track of the ImageView's bounds and then checking
* if the values change.
*/
if (top != mIvTop || bottom != mIvBottom || left != mIvLeft
|| right != mIvRight) {
// Update our base matrix, as the bounds have changed
updateBaseMatrix(imageView.getDrawable());
// Update values as something has changed
mIvTop = top;
mIvRight = right;
mIvBottom = bottom;
mIvLeft = left;
}
}
}
public final void onScale(float scaleFactor, float focusX, float focusY) {
if (getScale() < mMaxScale || scaleFactor < 1f) {
mSuppMatrix.postScale(scaleFactor, scaleFactor, focusX, focusY);
checkAndDisplayMatrix();
}
}
@Override
public final boolean onSingleTapConfirmed(MotionEvent e) {
ImageView imageView = getImageView();
if (null != mPhotoTapListener) {
final RectF displayRect = getDisplayRect();
if (null != displayRect) {
final float x = e.getX(), y = e.getY();
// Check to see if the user tapped on the photo
if (displayRect.contains(x, y)) {
float xResult = (x - displayRect.left)
/ displayRect.width();
float yResult = (y - displayRect.top)
/ displayRect.height();
mPhotoTapListener.onPhotoTap(imageView, xResult, yResult);
return true;
}
}
}
if (null != mViewTapListener) {
mViewTapListener.onViewTap(imageView, e.getX(), e.getY());
}
return false;
}
@Override
public final boolean onTouch(View v, MotionEvent ev) {
boolean handled = false;
if (mZoomEnabled && hasDrawable((ImageView) v)) {
ViewParent parent = v.getParent();
switch (ev.getAction()) {
case ACTION_DOWN:
// First, disable the Parent from intercepting the touch
// event
if (null != parent)
parent.requestDisallowInterceptTouchEvent(true);
else
Log.i(LOG_TAG, "onTouch getParent() returned null");
// If we're flinging, and the user presses down, cancel
// fling
cancelFling();
break;
case ACTION_CANCEL:
case ACTION_UP:
// If the user has zoomed less than min scale, zoom back
// to min scale
if (getScale() < mMinScale) {
RectF rect = getDisplayRect();
if (null != rect) {
v.post(new AnimatedZoomRunnable(getScale(), mMinScale,
rect.centerX(), rect.centerY()));
handled = true;
}
}
break;
}
// Check to see if the user double tapped
if (null != mGestureDetector && mGestureDetector.onTouchEvent(ev)) {
handled = true;
}
if (!handled && null != parent) {
parent.requestDisallowInterceptTouchEvent(false);
}
// Finally, try the Scale/Drag detector
if (null != mScaleDragDetector
&& mScaleDragDetector.onTouchEvent(ev)) {
handled = true;
}
}
return handled;
}
@Override
public void setAllowParentInterceptOnEdge(boolean allow) {
mAllowParentInterceptOnEdge = allow;
}
@Override
@Deprecated
public void setMinScale(float minScale) {
setMinimumScale(minScale);
}
@Override
public void setMinimumScale(float minimumScale) {
checkZoomLevels(minimumScale, mMidScale, mMaxScale);
mMinScale = minimumScale;
}
@Override
@Deprecated
public void setMidScale(float midScale) {
setMediumScale(midScale);
}
@Override
public void setMediumScale(float mediumScale) {
checkZoomLevels(mMinScale, mediumScale, mMaxScale);
mMidScale = mediumScale;
}
@Override
@Deprecated
public void setMaxScale(float maxScale) {
setMaximumScale(maxScale);
}
@Override
public void setMaximumScale(float maximumScale) {
checkZoomLevels(mMinScale, mMidScale, maximumScale);
mMaxScale = maximumScale;
}
@Override
public final void setOnLongClickListener(OnLongClickListener listener) {
mLongClickListener = listener;
}
@Override
public final void setOnMatrixChangeListener(OnMatrixChangedListener listener) {
mMatrixChangeListener = listener;
}
@Override
public final void setOnPhotoTapListener(OnPhotoTapListener listener) {
mPhotoTapListener = listener;
}
@Override
public final void setOnViewTapListener(OnViewTapListener listener) {
mViewTapListener = listener;
}
@Override
public void setScale(float scale) {
setScale(scale, false);
}
@Override
public void setScale(float scale, boolean animate) {
ImageView imageView = getImageView();
if (null != imageView) {
setScale(scale, (imageView.getRight()) / 2,
(imageView.getBottom()) / 2, animate);
}
}
@Override
public void setScale(float scale, float focalX, float focalY,
boolean animate) {
ImageView imageView = getImageView();
if (null != imageView) {
// Check to see if the scale is within bounds
if (scale < mMinScale || scale > mMaxScale) {
Log.i(LOG_TAG,
"Scale must be within the range of minScale and maxScale");
return;
}
if (animate) {
imageView.post(new AnimatedZoomRunnable(getScale(), scale,
focalX, focalY));
} else {
mSuppMatrix.setScale(scale, scale, focalX, focalY);
checkAndDisplayMatrix();
}
}
}
@Override
public final void setScaleType(ScaleType scaleType) {
if (isSupportedScaleType(scaleType) && scaleType != mScaleType) {
mScaleType = scaleType;
// Finally update
update();
}
}
@Override
public final void setZoomable(boolean zoomable) {
mZoomEnabled = zoomable;
update();
}
public final void update() {
ImageView imageView = getImageView();
if (null != imageView) {
if (mZoomEnabled) {
// Make sure we using MATRIX Scale Type
setImageViewScaleTypeMatrix(imageView);
// Update the base matrix using the current drawable
updateBaseMatrix(imageView.getDrawable());
} else {
// Reset the Matrix...
resetMatrix();
}
}
}
@Override
public Matrix getDisplayMatrix() {
return new Matrix(mSuppMatrix);
}
protected Matrix getDrawMatrix() {
mDrawMatrix.set(mBaseMatrix);
mDrawMatrix.postConcat(mSuppMatrix);
return mDrawMatrix;
}
private void cancelFling() {
if (null != mCurrentFlingRunnable) {
mCurrentFlingRunnable.cancelFling();
mCurrentFlingRunnable = null;
}
}
/**
* Helper method that simply checks the Matrix, and then displays the result
*/
private void checkAndDisplayMatrix() {
if (checkMatrixBounds()) {
setImageViewMatrix(getDrawMatrix());
}
}
private void checkImageViewScaleType() {
ImageView imageView = getImageView();
/**
* PhotoView's getScaleType() will just divert to this.getScaleType() so
* only call if we're not attached to a PhotoView.
*/
if (null != imageView && !(imageView instanceof PhotoView)) {
if (!ScaleType.MATRIX.equals(imageView.getScaleType())) {
throw new IllegalStateException(
"The ImageView's ScaleType has been changed since attaching a PhotoViewAttacher");
}
}
}
private boolean checkMatrixBounds() {
final ImageView imageView = getImageView();
if (null == imageView) {
return false;
}
final RectF rect = getDisplayRect(getDrawMatrix());
if (null == rect) {
return false;
}
final float height = rect.height(), width = rect.width();
float deltaX = 0, deltaY = 0;
final int viewHeight = getImageViewHeight(imageView);
if (height <= viewHeight) {
switch (mScaleType) {
case FIT_START:
deltaY = -rect.top;
break;
case FIT_END:
deltaY = viewHeight - height - rect.top;
break;
default:
deltaY = (viewHeight - height) / 2 - rect.top;
break;
}
} else if (rect.top > 0) {
deltaY = -rect.top;
} else if (rect.bottom < viewHeight) {
deltaY = viewHeight - rect.bottom;
}
final int viewWidth = getImageViewWidth(imageView);
if (width <= viewWidth) {
switch (mScaleType) {
case FIT_START:
deltaX = -rect.left;
break;
case FIT_END:
deltaX = viewWidth - width - rect.left;
break;
default:
deltaX = (viewWidth - width) / 2 - rect.left;
break;
}
mScrollEdge = EDGE_BOTH;
} else if (rect.left > 0) {
mScrollEdge = EDGE_LEFT;
deltaX = -rect.left;
} else if (rect.right < viewWidth) {
deltaX = viewWidth - rect.right;
mScrollEdge = EDGE_RIGHT;
} else {
mScrollEdge = EDGE_NONE;
}
// Finally actually translate the matrix
mSuppMatrix.postTranslate(deltaX, deltaY);
return true;
}
/**
* Helper method that maps the supplied Matrix to the current Drawable
*
* @param matrix
* - Matrix to map Drawable against
* @return RectF - Displayed Rectangle
*/
private RectF getDisplayRect(Matrix matrix) {
ImageView imageView = getImageView();
if (null != imageView) {
Drawable d = imageView.getDrawable();
if (null != d) {
mDisplayRect.set(0, 0, d.getIntrinsicWidth(),
d.getIntrinsicHeight());
matrix.mapRect(mDisplayRect);
return mDisplayRect;
}
}
return null;
}
/**
* Helper method that 'unpacks' a Matrix and returns the required value
*
* @param matrix
* - Matrix to unpack
* @param whichValue
* - Which value from Matrix.M* to return
* @return float - returned value
*/
private float getValue(Matrix matrix, int whichValue) {
matrix.getValues(mMatrixValues);
return mMatrixValues[whichValue];
}
/**
* Resets the Matrix back to FIT_CENTER, and then displays it.s
*/
private void resetMatrix() {
mSuppMatrix.reset();
setImageViewMatrix(getDrawMatrix());
checkMatrixBounds();
}
private void setImageViewMatrix(Matrix matrix) {
ImageView imageView = getImageView();
if (null != imageView) {
checkImageViewScaleType();
imageView.setImageMatrix(matrix);
// Call MatrixChangedListener if needed
if (null != mMatrixChangeListener) {
RectF displayRect = getDisplayRect(matrix);
if (null != displayRect) {
mMatrixChangeListener.onMatrixChanged(displayRect);
}
}
}
}
/**
* Calculate Matrix for FIT_CENTER
*
* @param d
* - Drawable being displayed
*/
private void updateBaseMatrix(Drawable d) {
ImageView imageView = getImageView();
if (null == imageView || null == d) {
return;
}
final float viewWidth = getImageViewWidth(imageView);
final float viewHeight = getImageViewHeight(imageView);
final int drawableWidth = d.getIntrinsicWidth();
final int drawableHeight = d.getIntrinsicHeight();
mBaseMatrix.reset();
final float widthScale = viewWidth / drawableWidth;
final float heightScale = viewHeight / drawableHeight;
if (mScaleType == ScaleType.CENTER) {
mBaseMatrix.postTranslate((viewWidth - drawableWidth) / 2F,
(viewHeight - drawableHeight) / 2F);
} else if (mScaleType == ScaleType.CENTER_CROP) {
float scale = Math.max(widthScale, heightScale);
mBaseMatrix.postScale(scale, scale);
mBaseMatrix.postTranslate((viewWidth - drawableWidth * scale) / 2F,
(viewHeight - drawableHeight * scale) / 2F);
} else if (mScaleType == ScaleType.CENTER_INSIDE) {
float scale = Math.min(1.0f, Math.min(widthScale, heightScale));
mBaseMatrix.postScale(scale, scale);
mBaseMatrix.postTranslate((viewWidth - drawableWidth * scale) / 2F,
(viewHeight - drawableHeight * scale) / 2F);
} else {
RectF mTempSrc = new RectF(0, 0, drawableWidth, drawableHeight);
RectF mTempDst = new RectF(0, 0, viewWidth, viewHeight);
switch (mScaleType) {
case FIT_CENTER:
mBaseMatrix
.setRectToRect(mTempSrc, mTempDst, ScaleToFit.CENTER);
break;
case FIT_START:
mBaseMatrix.setRectToRect(mTempSrc, mTempDst, ScaleToFit.START);
break;
case FIT_END:
mBaseMatrix.setRectToRect(mTempSrc, mTempDst, ScaleToFit.END);
break;
case FIT_XY:
mBaseMatrix.setRectToRect(mTempSrc, mTempDst, ScaleToFit.FILL);
break;
default:
break;
}
}
resetMatrix();
}
private int getImageViewWidth(ImageView imageView) {
if (null == imageView)
return 0;
return imageView.getWidth() - imageView.getPaddingLeft()
- imageView.getPaddingRight();
}
private int getImageViewHeight(ImageView imageView) {
if (null == imageView)
return 0;
return imageView.getHeight() - imageView.getPaddingTop()
- imageView.getPaddingBottom();
}
/**
* Interface definition for a callback to be invoked when the internal
* Matrix has changed for this View.
*
* @author Chris Banes
*/
public static interface OnMatrixChangedListener {
/**
* Callback for when the Matrix displaying the Drawable has changed.
* This could be because the View's bounds have changed, or the user has
* zoomed.
*
* @param rect
* - Rectangle displaying the Drawable's new bounds.
*/
void onMatrixChanged(RectF rect);
}
/**
* Interface definition for a callback to be invoked when the Photo is
* tapped with a single tap.
*
* @author Chris Banes
*/
public static interface OnPhotoTapListener {
/**
* A callback to receive where the user taps on a photo. You will only
* receive a callback if the user taps on the actual photo, tapping on
* 'whitespace' will be ignored.
*
* @param view
* - View the user tapped.
* @param x
* - where the user tapped from the of the Drawable, as
* percentage of the Drawable width.
* @param y
* - where the user tapped from the top of the Drawable, as
* percentage of the Drawable height.
*/
void onPhotoTap(View view, float x, float y);
}
/**
* Interface definition for a callback to be invoked when the ImageView is
* tapped with a single tap.
*
* @author Chris Banes
*/
public static interface OnViewTapListener {
/**
* A callback to receive where the user taps on a ImageView. You will
* receive a callback if the user taps anywhere on the view, tapping on
* 'whitespace' will not be ignored.
*
* @param view
* - View the user tapped.
* @param x
* - where the user tapped from the left of the View.
* @param y
* - where the user tapped from the top of the View.
*/
void onViewTap(View view, float x, float y);
}
private class AnimatedZoomRunnable implements Runnable {
private final float mFocalX, mFocalY;
private final long mStartTime;
private final float mZoomStart, mZoomEnd;
public AnimatedZoomRunnable(final float currentZoom,
final float targetZoom, final float focalX, final float focalY) {
mFocalX = focalX;
mFocalY = focalY;
mStartTime = System.currentTimeMillis();
mZoomStart = currentZoom;
mZoomEnd = targetZoom;
}
@Override
public void run() {
ImageView imageView = getImageView();
if (imageView == null) {
return;
}
float t = interpolate();
float scale = mZoomStart + t * (mZoomEnd - mZoomStart);
float deltaScale = scale / getScale();
mSuppMatrix.postScale(deltaScale, deltaScale, mFocalX, mFocalY);
checkAndDisplayMatrix();
// We haven't hit our target scale yet, so post ourselves again
if (t < 1f) {
Compat.postOnAnimation(imageView, this);
}
}
private float interpolate() {
float t = 1f * (System.currentTimeMillis() - mStartTime)
/ ZOOM_DURATION;
t = Math.min(1f, t);
t = sInterpolator.getInterpolation(t);
return t;
}
}
private class FlingRunnable implements Runnable {
private final ScrollerProxy mScroller;
private int mCurrentX, mCurrentY;
public FlingRunnable(Context context) {
mScroller = ScrollerProxy.getScroller(context);
}
public void cancelFling() {
mScroller.forceFinished(true);
}
public void fling(int viewWidth, int viewHeight, int velocityX,
int velocityY) {
final RectF rect = getDisplayRect();
if (null == rect) {
return;
}
final int startX = Math.round(-rect.left);
final int minX, maxX, minY, maxY;
if (viewWidth < rect.width()) {
minX = 0;
maxX = Math.round(rect.width() - viewWidth);
} else {
minX = maxX = startX;
}
final int startY = Math.round(-rect.top);
if (viewHeight < rect.height()) {
minY = 0;
maxY = Math.round(rect.height() - viewHeight);
} else {
minY = maxY = startY;
}
mCurrentX = startX;
mCurrentY = startY;
// If we actually can move, fling the scroller
if (startX != maxX || startY != maxY) {
mScroller.fling(startX, startY, velocityX, velocityY, minX,
maxX, minY, maxY, 0, 0);
}
}
@Override
public void run() {
if (mScroller.isFinished()) {
return; // remaining post that should not be handled
}
ImageView imageView = getImageView();
if (null != imageView && mScroller.computeScrollOffset()) {
final int newX = mScroller.getCurrX();
final int newY = mScroller.getCurrY();
mSuppMatrix.postTranslate(mCurrentX - newX, mCurrentY - newY);
setImageViewMatrix(getDrawMatrix());
mCurrentX = newX;
mCurrentY = newY;
// Post On animation
Compat.postOnAnimation(imageView, this);
}
}
}
}