Java tutorial
/* * Copyright (C) 2015 Jacob Klinker * * 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.onenews.widgets.sliding; import android.animation.Animator; import android.animation.Animator.AnimatorListener; import android.animation.AnimatorListenerAdapter; import android.animation.ObjectAnimator; import android.animation.ValueAnimator; import android.animation.ValueAnimator.AnimatorUpdateListener; import android.content.Context; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Point; import android.graphics.drawable.GradientDrawable; import android.os.Build; import android.support.design.widget.FloatingActionButton; import android.support.v7.widget.Toolbar; import android.util.AttributeSet; import android.util.TypedValue; import android.view.Display; import android.view.Gravity; import android.view.MotionEvent; import android.view.VelocityTracker; import android.view.View; import android.view.ViewConfiguration; import android.view.ViewGroup; import android.view.ViewTreeObserver; import android.view.WindowManager; import android.view.animation.AnimationUtils; import android.view.animation.DecelerateInterpolator; import android.view.animation.Interpolator; import android.view.animation.PathInterpolator; import android.widget.EdgeEffect; import android.widget.FrameLayout; import android.widget.ImageView; import android.widget.ScrollView; import android.widget.Scroller; import android.widget.TextView; import com.onenews.R; /** * A custom {@link ViewGroup} that operates similarly to a {@link ScrollView}, except with multiple * subviews. These subviews are scrolled or shrinked one at a time, until each reaches their * minimum or maximum value. * <p> * MultiShrinkScroller is designed for a specific problem. As such, this class is designed to be * used with a specific layout file: quickcontact_activity.xml. MultiShrinkScroller expects subviews * with specific ID values. * <p> * MultiShrinkScroller's code is heavily influenced by ScrollView. Nonetheless, several ScrollView * features are missing. For example: handling of KEYCODES, OverScroll bounce and saving * scroll state in savedInstanceState bundles. * <p> * Before copying this approach to nested scrolling, consider whether something simpler and less * customized will work for you. For example, see the re-usable StickyHeaderListView used by * WifiSetupActivity (very nice). Alternatively, check out Google+'s cover photo scrolling or * Android L's built in nested scrolling support. I thought I needed a more custom ViewGroup in * order to track velocity, modify EdgeEffect color and perform the originally specified animations. * As a result this ViewGroup has non-standard talkback and keyboard support. */ public class MultiShrinkScroller extends FrameLayout { public enum OpenAnimation { SLIDE_UP, EXPAND_FROM_VIEW } /** * 1000 pixels per millisecond. Ie, 1 pixel per second. */ private static final int PIXELS_PER_SECOND = 1000; /** * The duration that the activity should take to animate onto screen. */ public static final int ANIMATION_DURATION = 300; /** * Length of the acceleration animations. This value was taken from ValueAnimator.java. */ private static final int EXIT_FLING_ANIMATION_DURATION_MS = 250; /** * In portrait mode, the height:width ratio of the photo's starting height. */ private static final float INTERMEDIATE_HEADER_HEIGHT_RATIO = 0.6f; /** * Color blending will only be performed on the contact photo once the toolbar is compressed * to this ratio of its full height. */ private static final float COLOR_BLENDING_START_RATIO = 0.5f; /** * Dampen the animations slightly. */ private static final float SPRING_DAMPENING_FACTOR = 0.01f; private float[] lastEventPosition = { 0, 0 }; private VelocityTracker velocityTracker; private boolean isBeingDragged = false; private boolean receivedDown = false; private boolean isFullscreenDownwardsFling = false; private ScrollView scrollView; private View scrollViewChild; private View toolbar; private ImageView photoView; private FloatingActionButton fab; private View photoViewContainer; private View transparentView; private MultiShrinkScrollerListener listener; private TextView largeTextView; private View photoTouchInterceptOverlay; private TextView invisiblePlaceholderTextView; private View titleGradientView; private View actionBarGradientView; private View startColumn; private int headerTintColor; private int maximumHeaderHeight; private int minimumHeaderHeight; private int intermediateHeaderHeight; private boolean isOpenImageSquare; private int maximumHeaderTextSize; private int collapsedTitleBottomMargin; private int collapsedTitleStartMargin; private boolean hasEverTouchedTheTop; private boolean isTouchDisabledForDismissAnimation; private boolean enableFab = false; private final Scroller scroller; private final EdgeEffect edgeGlowBottom; private final EdgeEffect edgeGlowTop; private final int touchSlop; private final int maximumVelocity; private final int minimumVelocity; private final int dismissDistanceOnScroll; private final int dismissDistanceOnRelease; private final int snapToTopSlopHeight; private final int transparentStartHeight; private final int maximumTitleMargin; private final float toolbarElevation; private final boolean isTwoPanel; private final float landscapePhotoRatio; private final int actionBarSize; private static final float X1 = 0.16f; private static final float Y1 = 0.4f; private static final float X2 = 0.2f; private static final float Y2 = 1f; private final PathInterpolator textSizePathInterpolator; private final int[] gradientColors = new int[] { 0, 0x88000000 }; private GradientDrawable titleGradientDrawable = new GradientDrawable(GradientDrawable.Orientation.TOP_BOTTOM, gradientColors); private GradientDrawable actionBarGradientDrawable = new GradientDrawable( GradientDrawable.Orientation.BOTTOM_TOP, gradientColors); /** * Interface for listening to scroll events. */ public interface MultiShrinkScrollerListener { void onScrolledOffBottom(); void onStartScrollOffBottom(); void onTransparentViewHeightChange(float ratio); void onEntranceAnimationDone(); void onEnterFullscreen(); void onExitFullscreen(); } /** * Listener for snapping the content to the bottom of the screen. */ private final AnimatorListener exitAnimationListner = new AnimatorListenerAdapter() { @Override public void onAnimationEnd(Animator animation) { if ((getScrollUntilOffBottom() > 0 || openAnimation == OpenAnimation.EXPAND_FROM_VIEW) && listener != null) { // Due to a rounding error, after the animation finished we haven't fully scrolled // off the screen. Lie to the listener: tell it that we did scroll off the screen. listener.onScrolledOffBottom(); // No other messages need to be sent to the listener. listener = null; } } }; /** * Interpolator from android.support.v4.view.ViewPager. Snappier and more elastic feeling * than the default interpolator. */ private static final Interpolator INTERPOLATOR = new Interpolator() { /** * {@inheritDoc} */ @Override public float getInterpolation(float t) { t -= 1.0f; return t * t * t * t * t + 1.0f; } }; /** * Create a new instance of MultiShrinkScroller. * * @param context */ public MultiShrinkScroller(Context context) { this(context, null); } /** * Create a new instance of MultiShrinkScroller. * * @param context * @param attrs */ public MultiShrinkScroller(Context context, AttributeSet attrs) { this(context, attrs, 0); } /** * Create a new instance of MultiShrinkScroller. * * @param context * @param attrs * @param defStyleAttr */ public MultiShrinkScroller(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); final ViewConfiguration configuration = ViewConfiguration.get(context); setFocusable(false); setWillNotDraw(false); edgeGlowBottom = new EdgeEffect(context); edgeGlowTop = new EdgeEffect(context); scroller = new Scroller(context, INTERPOLATOR); touchSlop = configuration.getScaledTouchSlop(); minimumVelocity = configuration.getScaledMinimumFlingVelocity(); maximumVelocity = configuration.getScaledMaximumFlingVelocity(); transparentStartHeight = (int) getResources().getDimension(R.dimen.sliding_starting_empty_height); toolbarElevation = getResources().getDimension(R.dimen.sliding_toolbar_elevation); isTwoPanel = getResources().getBoolean(R.bool.sliding_two_panel); maximumTitleMargin = (int) getResources().getDimension(R.dimen.sliding_title_initial_margin); dismissDistanceOnScroll = (int) getResources().getDimension(R.dimen.sliding_dismiss_distance_on_scroll); dismissDistanceOnRelease = (int) getResources().getDimension(R.dimen.sliding_dismiss_distance_on_release); snapToTopSlopHeight = (int) getResources().getDimension(R.dimen.sliding_snap_to_top_slop_height); final TypedValue photoRatio = new TypedValue(); getResources().getValue(R.dimen.sliding_landscape_photo_ratio, photoRatio, true); landscapePhotoRatio = photoRatio.getFloat(); final TypedArray attributeArray = context .obtainStyledAttributes(new int[] { android.R.attr.actionBarSize }); actionBarSize = attributeArray.getDimensionPixelSize(0, 0); minimumHeaderHeight = actionBarSize; attributeArray.recycle(); if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { textSizePathInterpolator = new PathInterpolator(X1, Y1, X2, Y2); } else { textSizePathInterpolator = null; } } /** * This method must be called inside the Activity's onCreate. Initialize everything. */ public void initialize(MultiShrinkScrollerListener listener, boolean isOpenContactSquare) { scrollView = (ScrollView) findViewById(R.id.content_scroller); scrollViewChild = findViewById(R.id.content_container); toolbar = findViewById(R.id.toolbar_parent); photoViewContainer = findViewById(R.id.toolbar_parent); transparentView = findViewById(R.id.transparent_view); largeTextView = (TextView) findViewById(R.id.large_title); invisiblePlaceholderTextView = (TextView) findViewById(R.id.placeholder_textview); startColumn = findViewById(R.id.empty_start_column); // Touching the empty space should close the card if (startColumn != null) { startColumn.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { scrollOffBottom(); } }); findViewById(R.id.empty_end_column).setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { scrollOffBottom(); } }); } this.listener = listener; this.isOpenImageSquare = isOpenContactSquare; photoView = (ImageView) findViewById(R.id.photo); fab = (FloatingActionButton) findViewById(R.id.fab); titleGradientView = findViewById(R.id.title_gradient); titleGradientView.setBackgroundDrawable(titleGradientDrawable); actionBarGradientView = findViewById(R.id.action_bar_gradient); actionBarGradientView.setBackgroundDrawable(actionBarGradientDrawable); collapsedTitleStartMargin = ((Toolbar) findViewById(R.id.toolbar)).getContentInsetStart(); photoTouchInterceptOverlay = findViewById(R.id.photo_touch_intercept_overlay); if (!isTwoPanel) { photoTouchInterceptOverlay.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { expandHeader(); } }); } else { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { scrollView.setOnScrollChangeListener(new OnScrollChangeListener() { @Override public void onScrollChange(View v, int scrollX, int scrollY, int oldScrollX, int oldScrollY) { updateFabStatus(scrollY); } }); } else { scrollView.getViewTreeObserver() .addOnScrollChangedListener(new ViewTreeObserver.OnScrollChangedListener() { @Override public void onScrollChanged() { updateFabStatus(scrollView.getScrollY()); } }); } } SchedulingUtils.doOnPreDraw(this, false, new Runnable() { @Override public void run() { if (!isTwoPanel) { maximumHeaderHeight = getResources().getDimensionPixelSize(R.dimen.sliding_header_max_height); intermediateHeaderHeight = (int) (maximumHeaderHeight * INTERMEDIATE_HEADER_HEIGHT_RATIO); } setHeaderHeight(getMaximumScrollableHeaderHeight()); maximumHeaderTextSize = largeTextView.getHeight(); if (isTwoPanel) { maximumHeaderHeight = getHeight(); minimumHeaderHeight = maximumHeaderHeight; intermediateHeaderHeight = maximumHeaderHeight; // Permanently set photo width and height. final ViewGroup.LayoutParams photoLayoutParams = photoViewContainer.getLayoutParams(); photoLayoutParams.height = maximumHeaderHeight; photoLayoutParams.width = (int) (maximumHeaderHeight * landscapePhotoRatio); photoViewContainer.setLayoutParams(photoLayoutParams); // Permanently set title width and margin. final LayoutParams largeTextLayoutParams = (LayoutParams) largeTextView.getLayoutParams(); largeTextLayoutParams.width = photoLayoutParams.width - largeTextLayoutParams.leftMargin - largeTextLayoutParams.rightMargin; largeTextLayoutParams.gravity = Gravity.BOTTOM | Gravity.START; largeTextView.setLayoutParams(largeTextLayoutParams); } else { // Set the width of largeTextView as if it was nested inside // photoViewContainer. largeTextView.setWidth(photoViewContainer.getWidth() - 2 * maximumTitleMargin); } calculateCollapsedLargeTitlePadding(); updateHeaderTextSizeAndMargin(); configureGradientViewHeights(); } }); } private void configureGradientViewHeights() { final LayoutParams actionBarGradientLayoutParams = (LayoutParams) actionBarGradientView.getLayoutParams(); actionBarGradientLayoutParams.height = actionBarSize; actionBarGradientView.setLayoutParams(actionBarGradientLayoutParams); final LayoutParams titleGradientLayoutParams = (LayoutParams) titleGradientView.getLayoutParams(); final float TITLE_GRADIENT_SIZE_COEFFICIENT = 1.25f; final LayoutParams largeTextLayoutParms = (LayoutParams) largeTextView.getLayoutParams(); titleGradientLayoutParams.height = (int) ((largeTextView.getHeight() + largeTextLayoutParms.bottomMargin) * TITLE_GRADIENT_SIZE_COEFFICIENT); titleGradientView.setLayoutParams(titleGradientLayoutParams); } /** * Set the title for the large text view that will be adjusted as the activity scrolls. * * @param title the title. */ public void setTitle(String title) { largeTextView.setText(title); photoTouchInterceptOverlay.setContentDescription(title); largeTextView.setAlpha(0f); largeTextView.animate().alpha(1f).start(); } /** * Disables the header at the top of the activity, only the content will be shown. */ public void disableHeader() { intermediateHeaderHeight = 0; maximumHeaderHeight = 0; minimumHeaderHeight = 0; largeTextView.setVisibility(View.GONE); ((View) photoView.getParent()).setVisibility(View.GONE); } /** * Catch the touch event and act on it. * * @param event the touch event. * @return true if we should start dragging, otherwise false. */ @Override public boolean onInterceptTouchEvent(MotionEvent event) { if (velocityTracker == null) { velocityTracker = VelocityTracker.obtain(); } velocityTracker.addMovement(event); // The only time we want to intercept touch events is when we are being dragged. return shouldStartDrag(event); } private boolean shouldStartDrag(MotionEvent event) { if (isTouchDisabledForDismissAnimation) return false; if (isBeingDragged) { isBeingDragged = false; return false; } switch (event.getAction()) { // If we are in the middle of a fling and there is a down event, we'll steal it and // start a drag. case MotionEvent.ACTION_DOWN: updateLastEventPosition(event); if (!scroller.isFinished()) { startDrag(); return true; } else { receivedDown = true; } break; // Otherwise, we will start a drag if there is enough motion in the direction we are // capable of scrolling. case MotionEvent.ACTION_MOVE: if (motionShouldStartDrag(event)) { updateLastEventPosition(event); startDrag(); return true; } break; } return false; } /** * Catch the touch event and act on it. * * @param event the touch event. */ @Override public boolean onTouchEvent(MotionEvent event) { if (isTouchDisabledForDismissAnimation) return true; final int action = event.getAction(); if (velocityTracker == null) { velocityTracker = VelocityTracker.obtain(); } velocityTracker.addMovement(event); if (!isBeingDragged) { if (shouldStartDrag(event)) { return true; } if (action == MotionEvent.ACTION_UP && receivedDown) { receivedDown = false; return performClick(); } return true; } switch (action) { case MotionEvent.ACTION_MOVE: final float delta = updatePositionAndComputeDelta(event); scrollTo(0, getScroll() + (int) delta); receivedDown = false; if (isBeingDragged) { final int distanceFromMaxScrolling = getMaximumScrollUpwards() - getScroll(); if (delta > distanceFromMaxScrolling && Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { // The ScrollView is being pulled upwards while there is no more // content offscreen, and the view port is already fully expanded. edgeGlowBottom.onPull(delta / getHeight(), 1 - event.getX() / getWidth()); } if (!edgeGlowBottom.isFinished()) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) { postInvalidateOnAnimation(); } else { postInvalidate(); } } if (shouldDismissOnScroll()) { scrollOffBottom(); } } break; case MotionEvent.ACTION_UP: case MotionEvent.ACTION_CANCEL: stopDrag(action == MotionEvent.ACTION_CANCEL); receivedDown = false; break; } return true; } /** * Sets the tint color that should be applied to the header. If an image is present, this * will go behind the image and show over it as the activity is scrolled, otherwise it will * just be the color displayed at the top of the screen. * * @param color the primary color for the activity to display. */ public void setHeaderTintColor(int color) { headerTintColor = color; updatePhotoTintAndDropShadow(); // We want to use the same amount of alpha on the new tint color as the previous tint color. if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { final int edgeEffectAlpha = Color.alpha(edgeGlowBottom.getColor()); edgeGlowBottom.setColor((color & 0xffffff) | Color.argb(edgeEffectAlpha, 0, 0, 0)); edgeGlowTop.setColor(edgeGlowBottom.getColor()); } } /** * Expand to maximum size. */ private void expandHeader() { if (getHeaderHeight() != maximumHeaderHeight) { final ObjectAnimator animator = ObjectAnimator.ofInt(this, "headerHeight", maximumHeaderHeight); animator.setDuration(ANIMATION_DURATION); animator.start(); // Scroll nested scroll view to its top if (scrollView.getScrollY() != 0) { ObjectAnimator.ofInt(scrollView, "scrollY", -scrollView.getScrollY()).start(); } } } private void startDrag() { isBeingDragged = true; scroller.abortAnimation(); } private void stopDrag(boolean cancelled) { isBeingDragged = false; if (!cancelled && getChildCount() > 0) { final float velocity = getCurrentVelocity(); if (velocity > minimumVelocity || velocity < -minimumVelocity) { fling(-velocity); onDragFinished(scroller.getFinalY() - scroller.getStartY()); } else { onDragFinished(/* flingDelta = */ 0); } } else { onDragFinished(/* flingDelta = */ 0); } if (velocityTracker != null) { velocityTracker.recycle(); velocityTracker = null; } edgeGlowBottom.onRelease(); } private void onDragFinished(int flingDelta) { if (getTransparentViewHeight() <= 0) { // Don't perform any snapping if quick contacts is full screen. return; } if (!snapToTopOnDragFinished(flingDelta)) { // The drag/fling won't result in the content at the top of the Window. Consider // snapping the content to the bottom of the window. snapToBottomOnDragFinished(); } } /** * If needed, snap the subviews to the top of the Window. * * @return TRUE if QuickContacts will snap/fling to to top after this method call. */ private boolean snapToTopOnDragFinished(int flingDelta) { if (!hasEverTouchedTheTop) { // If the current fling is predicted to scroll past the top, then we don't need to snap // to the top. However, if the fling only flings past the top by a tiny amount, // it will look nicer to snap than to fling. final float predictedScrollPastTop = getTransparentViewHeight() - flingDelta; if (predictedScrollPastTop < -snapToTopSlopHeight) { return false; } if (getTransparentViewHeight() <= transparentStartHeight) { // We are above the starting scroll position so snap to the top. scroller.forceFinished(true); smoothScrollBy(getTransparentViewHeight()); return true; } return false; } if (getTransparentViewHeight() < dismissDistanceOnRelease) { scroller.forceFinished(true); smoothScrollBy(getTransparentViewHeight()); return true; } return false; } /** * If needed, scroll all the subviews off the bottom of the Window. */ private void snapToBottomOnDragFinished() { if (hasEverTouchedTheTop) { if (getTransparentViewHeight() > dismissDistanceOnRelease) { scrollOffBottom(); } return; } if (getTransparentViewHeight() > transparentStartHeight) { scrollOffBottom(); } } /** * Returns TRUE if we have scrolled far QuickContacts far enough that we should dismiss it * without waiting for the user to finish their drag. */ private boolean shouldDismissOnScroll() { return hasEverTouchedTheTop && getTransparentViewHeight() > dismissDistanceOnScroll; } /** * Return ratio of non-transparent:viewgroup-height for this viewgroup at the starting position. */ public float getStartingTransparentHeightRatio() { return getTransparentHeightRatio(transparentStartHeight); } private float getTransparentHeightRatio(int transparentHeight) { final float heightRatio = (float) transparentHeight / getHeight(); // Clamp between [0, 1] in case this is called before height is initialized. return 1.0f - Math.max(Math.min(1.0f, heightRatio), 0f); } public boolean willUseReverseExpansion() { return openAnimation == OpenAnimation.EXPAND_FROM_VIEW && hasEverTouchedTheTop; } /** * Scroll the activity off the bottom of the screen. */ public void scrollOffBottom() { isTouchDisabledForDismissAnimation = true; scroller.forceFinished(true); if (!willUseReverseExpansion()) { final Interpolator interpolator = new AcceleratingFlingInterpolator(EXIT_FLING_ANIMATION_DURATION_MS, getCurrentVelocity(), getScrollUntilOffBottom()); ObjectAnimator translateAnimation = ObjectAnimator.ofInt(this, "scroll", getScroll() - getScrollUntilOffBottom()); translateAnimation.setRepeatCount(0); translateAnimation.setInterpolator(interpolator); translateAnimation.setDuration(EXIT_FLING_ANIMATION_DURATION_MS); translateAnimation.addListener(exitAnimationListner); translateAnimation.start(); } else { reverseExpansionAnimation(); } if (listener != null) { listener.onStartScrollOffBottom(); } } /** * Scroll the activity up as the entrace animation. * * @param scrollToCurrentPosition if true, will scroll from the bottom of the screen to the * current position. Otherwise, will scroll from the bottom of the screen to the top of the * screen. */ public void performEntranceAnimation(OpenAnimation animation, boolean scrollToCurrentPosition) { final int currentPosition = getScroll(); final int bottomScrollPosition = currentPosition - (getHeight() - getTransparentViewHeight()) + 1; final int desiredValue = currentPosition + (scrollToCurrentPosition ? currentPosition : getTransparentViewHeight()); if (animation == OpenAnimation.EXPAND_FROM_VIEW) { scrollTo(0, desiredValue); runExpansionAnimation(); openAnimation = animation; } else { final Interpolator interpolator; if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { interpolator = AnimationUtils.loadInterpolator(getContext(), android.R.interpolator.linear_out_slow_in); } else { interpolator = new DecelerateInterpolator(); } final ObjectAnimator animator = ObjectAnimator.ofInt(this, "scroll", bottomScrollPosition, desiredValue); animator.setInterpolator(interpolator); animator.addUpdateListener(new AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { if (animation.getAnimatedValue().equals(desiredValue) && listener != null) { listener.onEntranceAnimationDone(); } } }); animator.start(); } } private OpenAnimation openAnimation = OpenAnimation.SLIDE_UP; private int expansionLeftOffset; private int expansionTopOffset; private int expansionViewWidth; private int expansionViewHeight; public void setExpansionPoints(int leftOffset, int topOffset, int viewWidth, int viewHeight) { this.expansionLeftOffset = leftOffset; this.expansionTopOffset = topOffset; this.expansionViewWidth = viewWidth; this.expansionViewHeight = viewHeight; } public void runExpansionAnimation() { final Interpolator interpolator; if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { interpolator = AnimationUtils.loadInterpolator(getContext(), android.R.interpolator.linear_out_slow_in); } else { interpolator = new DecelerateInterpolator(); } WindowManager wm = (WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE); Display display = wm.getDefaultDisplay(); Point size = new Point(); display.getSize(size); int screenHeight = size.y; int screenWidth = size.x; final ValueAnimator heightExpansion = ValueAnimator.ofInt(expansionViewHeight, getHeight()); heightExpansion.setInterpolator(interpolator); heightExpansion.setDuration(ANIMATION_DURATION); heightExpansion.addUpdateListener(new AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { int val = (int) animation.getAnimatedValue(); ViewGroup.LayoutParams params = getLayoutParams(); params.height = val; setLayoutParams(params); } }); heightExpansion.start(); final ValueAnimator widthExpansion = ValueAnimator.ofInt(expansionViewWidth, getWidth()); widthExpansion.setInterpolator(interpolator); widthExpansion.setDuration(ANIMATION_DURATION); widthExpansion.addUpdateListener(new AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { int val = (int) animation.getAnimatedValue(); ViewGroup.LayoutParams params = getLayoutParams(); params.width = val; setLayoutParams(params); } }); widthExpansion.start(); ObjectAnimator translationX = ObjectAnimator.ofFloat(this, View.TRANSLATION_X, expansionLeftOffset, 0f); translationX.setInterpolator(interpolator); translationX.setDuration(ANIMATION_DURATION); translationX.start(); ObjectAnimator translationY = ObjectAnimator.ofFloat(this, View.TRANSLATION_Y, expansionTopOffset, 0f); translationY.setInterpolator(interpolator); translationY.setDuration(ANIMATION_DURATION); translationY.start(); } public void reverseExpansionAnimation() { final Interpolator interpolator; if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { interpolator = AnimationUtils.loadInterpolator(getContext(), android.R.interpolator.linear_out_slow_in); } else { interpolator = new DecelerateInterpolator(); } WindowManager wm = (WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE); Display display = wm.getDefaultDisplay(); Point size = new Point(); display.getSize(size); int screenHeight = size.y; int screenWidth = size.x; final ValueAnimator heightExpansion = ValueAnimator.ofInt(screenHeight, expansionViewHeight); heightExpansion.setInterpolator(interpolator); heightExpansion.setDuration(ANIMATION_DURATION); heightExpansion.addUpdateListener(new AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { int val = (int) animation.getAnimatedValue(); ViewGroup.LayoutParams params = getLayoutParams(); params.height = val; setLayoutParams(params); } }); heightExpansion.start(); final ValueAnimator widthExpansion = ValueAnimator.ofInt(getWidth(), expansionViewWidth); widthExpansion.setInterpolator(interpolator); widthExpansion.setDuration(ANIMATION_DURATION); widthExpansion.addUpdateListener(new AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { int val = (int) animation.getAnimatedValue(); ViewGroup.LayoutParams params = getLayoutParams(); params.width = val; setLayoutParams(params); } }); widthExpansion.start(); ObjectAnimator translationX = ObjectAnimator.ofFloat(this, View.TRANSLATION_X, 0f, expansionLeftOffset); translationX.setInterpolator(interpolator); translationX.setDuration(ANIMATION_DURATION); translationX.start(); ObjectAnimator translationY = ObjectAnimator.ofFloat(this, View.TRANSLATION_Y, 0f, expansionTopOffset); translationY.setInterpolator(interpolator); translationY.setDuration(ANIMATION_DURATION); translationY.addListener(exitAnimationListner); translationY.start(); } /** * Scroll to a certain position. * * @param x the x position. * @param y the y position. */ @Override public void scrollTo(int x, int y) { final int delta = y - getScroll(); boolean wasFullscreen = getScrollNeededToBeFullScreen() <= 0; if (delta > 0) { scrollUp(delta); } else { scrollDown(delta); } updatePhotoTintAndDropShadow(); updateHeaderTextSizeAndMargin(); updateFabStatus(); final boolean isFullscreen = getScrollNeededToBeFullScreen() <= 0; hasEverTouchedTheTop |= isFullscreen; if (listener != null) { if (wasFullscreen && !isFullscreen) { listener.onExitFullscreen(); } else if (!wasFullscreen && isFullscreen) { listener.onEnterFullscreen(); } if (!isFullscreen || !wasFullscreen) { listener.onTransparentViewHeightChange(getTransparentHeightRatio(getTransparentViewHeight())); } } } /** * Get the current toolbar height. * * @return the toolbar height. */ public int getToolbarHeight() { return toolbar.getLayoutParams().height; } /** * Set the height of the toolbar and update its tint accordingly. */ public void setHeaderHeight(int height) { final ViewGroup.LayoutParams toolbarLayoutParams = toolbar.getLayoutParams(); toolbarLayoutParams.height = height; toolbar.setLayoutParams(toolbarLayoutParams); updatePhotoTintAndDropShadow(); updateHeaderTextSizeAndMargin(); } /** * Gets the current header height. * * @return the header height. */ public int getHeaderHeight() { return toolbar.getLayoutParams().height; } /** * Set where to scroll to. * * @param scroll the y scroll position. */ public void setScroll(int scroll) { scrollTo(0, scroll); } /** * Returns the total amount scrolled inside the nested ScrollView + the amount of shrinking * performed on the ToolBar. This is the value inspected by animators. */ public int getScroll() { return transparentStartHeight - getTransparentViewHeight() + getMaximumScrollableHeaderHeight() - getToolbarHeight() + scrollView.getScrollY(); } private int getMaximumScrollableHeaderHeight() { return isOpenImageSquare ? maximumHeaderHeight : intermediateHeaderHeight; } /** * A variant of {@link #getScroll} that pretends the header is never larger than * than intermediateHeaderHeight. This function is sometimes needed when making scrolling * decisions that will not change the header size (ie, snapping to the bottom or top). * <p> * When isOpenImageSquare is true, this function considers intermediateHeaderHeight == * maximumHeaderHeight, since snapping decisions will be made relative the full header * size when isOpenImageSquare = true. * <p> * This value should never be used in conjunction with {@link #getScroll} values. */ private int getScroll_ignoreOversizedHeaderForSnapping() { return transparentStartHeight - getTransparentViewHeight() + Math.max(getMaximumScrollableHeaderHeight() - getToolbarHeight(), 0) + scrollView.getScrollY(); } /** * Amount of transparent space above the header/toolbar. */ public int getScrollNeededToBeFullScreen() { return getTransparentViewHeight(); } /** * Return amount of scrolling needed in order for all the visible subviews to scroll off the * bottom. */ private int getScrollUntilOffBottom() { return getHeight() + getScroll_ignoreOversizedHeaderForSnapping() - transparentStartHeight; } /** * Compute the scroll for the action. */ @Override public void computeScroll() { if (scroller.computeScrollOffset()) { // Examine the fling results in order to activate EdgeEffect and halt flings. final int oldScroll = getScroll(); scrollTo(0, scroller.getCurrY()); final int delta = scroller.getCurrY() - oldScroll; final int distanceFromMaxScrolling = getMaximumScrollUpwards() - getScroll(); if (delta > distanceFromMaxScrolling && distanceFromMaxScrolling > 0) { edgeGlowBottom.onAbsorb((int) scroller.getCurrVelocity()); } if (isFullscreenDownwardsFling && getTransparentViewHeight() > 0) { // Halt the fling once QuickContact's top is on screen. scrollTo(0, getScroll() + getTransparentViewHeight()); edgeGlowTop.onAbsorb((int) scroller.getCurrVelocity()); scroller.abortAnimation(); isFullscreenDownwardsFling = false; } if (!awakenScrollBars()) { // Keep on drawing until the animation has finished. if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) { postInvalidateOnAnimation(); } else { postInvalidate(); } } if (scroller.getCurrY() >= getMaximumScrollUpwards()) { // Halt the fling once QuickContact's bottom is on screen. scroller.abortAnimation(); isFullscreenDownwardsFling = false; } } } /** * Draw all components on the screen. * * @param canvas the canvas to draw on. */ @Override public void draw(Canvas canvas) { super.draw(canvas); final int width = getWidth() - getPaddingLeft() - getPaddingRight(); final int height = getHeight(); if (!edgeGlowBottom.isFinished()) { final int restoreCount = canvas.save(); // Draw the EdgeEffect on the bottom of the Window (Or a little bit below the bottom // of the Window if we start to scroll upwards while EdgeEffect is visible). This // does not need to consider the case where this MultiShrinkScroller doesn't fill // the Window, since the nested ScrollView should be set to fillViewport. canvas.translate(-width + getPaddingLeft(), height + getMaximumScrollUpwards() - getScroll()); canvas.rotate(180, width, 0); if (isTwoPanel) { // Only show the EdgeEffect on the bottom of the ScrollView. edgeGlowBottom.setSize(scrollView.getWidth(), height); } else { edgeGlowBottom.setSize(width, height); } if (edgeGlowBottom.draw(canvas)) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) { postInvalidateOnAnimation(); } else { postInvalidate(); } } canvas.restoreToCount(restoreCount); } if (!edgeGlowTop.isFinished()) { final int restoreCount = canvas.save(); if (isTwoPanel) { edgeGlowTop.setSize(scrollView.getWidth(), height); canvas.translate(photoViewContainer.getWidth(), 0); } else { edgeGlowTop.setSize(width, height); } if (edgeGlowTop.draw(canvas)) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) { postInvalidateOnAnimation(); } else { postInvalidate(); } } canvas.restoreToCount(restoreCount); } } private float getCurrentVelocity() { if (velocityTracker == null) { return 0; } velocityTracker.computeCurrentVelocity(PIXELS_PER_SECOND, maximumVelocity); return velocityTracker.getYVelocity(); } private void fling(float velocity) { // For reasons I do not understand, scrolling is less janky when maxY=Integer.MAX_VALUE // then when maxY is set to an actual value. scroller.fling(0, getScroll(), 0, (int) velocity, 0, 0, -Integer.MAX_VALUE, Integer.MAX_VALUE); if (velocity < 0 && transparentView.getHeight() <= 0) { isFullscreenDownwardsFling = true; } invalidate(); } private int getMaximumScrollUpwards() { if (!isTwoPanel) { return transparentStartHeight // How much the Header view can compress + getMaximumScrollableHeaderHeight() - getFullyCompressedHeaderHeight() // How much the ScrollView can scroll. 0, if child is smaller than ScrollView. + Math.max(0, scrollViewChild.getHeight() - getHeight() + getFullyCompressedHeaderHeight()); } else { return transparentStartHeight // How much the ScrollView can scroll. 0, if child is smaller than ScrollView. + Math.max(0, scrollViewChild.getHeight() - getHeight()); } } private int getTransparentViewHeight() { return transparentView.getLayoutParams().height; } private void setTransparentViewHeight(int height) { transparentView.getLayoutParams().height = height; transparentView.setLayoutParams(transparentView.getLayoutParams()); } private void scrollUp(int delta) { if (getTransparentViewHeight() != 0) { final int originalValue = getTransparentViewHeight(); setTransparentViewHeight(getTransparentViewHeight() - delta); setTransparentViewHeight(Math.max(0, getTransparentViewHeight())); delta -= originalValue - getTransparentViewHeight(); } final ViewGroup.LayoutParams toolbarLayoutParams = toolbar.getLayoutParams(); if (toolbarLayoutParams.height > getFullyCompressedHeaderHeight()) { final int originalValue = toolbarLayoutParams.height; toolbarLayoutParams.height -= delta; toolbarLayoutParams.height = Math.max(toolbarLayoutParams.height, getFullyCompressedHeaderHeight()); toolbar.setLayoutParams(toolbarLayoutParams); delta -= originalValue - toolbarLayoutParams.height; } scrollView.scrollBy(0, delta); } /** * Returns the minimum size that we want to compress the header to, given that we don't want to * allow the the ScrollView to scroll unless there is new content off of the edge of ScrollView. */ private int getFullyCompressedHeaderHeight() { return Math.min( Math.max(toolbar.getLayoutParams().height - getOverflowingChildViewSize(), minimumHeaderHeight), getMaximumScrollableHeaderHeight()); } /** * Returns the amount of scrollViewChild that doesn't fit inside its parent. */ private int getOverflowingChildViewSize() { final int usedScrollViewSpace = scrollViewChild.getHeight(); return -getHeight() + usedScrollViewSpace + toolbar.getLayoutParams().height; } private void scrollDown(int delta) { if (scrollView.getScrollY() > 0) { final int originalValue = scrollView.getScrollY(); scrollView.scrollBy(0, delta); delta -= scrollView.getScrollY() - originalValue; } final ViewGroup.LayoutParams toolbarLayoutParams = toolbar.getLayoutParams(); if (toolbarLayoutParams.height < getMaximumScrollableHeaderHeight()) { final int originalValue = toolbarLayoutParams.height; toolbarLayoutParams.height -= delta; toolbarLayoutParams.height = Math.min(toolbarLayoutParams.height, getMaximumScrollableHeaderHeight()); toolbar.setLayoutParams(toolbarLayoutParams); delta -= originalValue - toolbarLayoutParams.height; } setTransparentViewHeight(getTransparentViewHeight() - delta); if (getScrollUntilOffBottom() <= 0) { post(new Runnable() { @Override public void run() { if (listener != null) { listener.onScrolledOffBottom(); // No other messages need to be sent to the listener. listener = null; } } }); } } /** * Set the header size and padding, based on the current scroll position. */ private void updateHeaderTextSizeAndMargin() { if (isTwoPanel) { // The text size stays at a constant size & location in two panel layouts. return; } // The pivot point for scaling should be middle of the starting side. largeTextView.setPivotX(0); largeTextView.setPivotY(largeTextView.getHeight() / 2); final int toolbarHeight = toolbar.getLayoutParams().height; photoTouchInterceptOverlay.setClickable(toolbarHeight != maximumHeaderHeight); if (toolbarHeight >= maximumHeaderHeight) { // Everything is full size when the header is fully expanded. largeTextView.setScaleX(1); largeTextView.setScaleY(1); setInterpolatedTitleMargins(1); return; } final float ratio = (toolbarHeight - minimumHeaderHeight) / (float) (maximumHeaderHeight - minimumHeaderHeight); final float minimumSize = invisiblePlaceholderTextView.getHeight(); float bezierOutput; if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { bezierOutput = textSizePathInterpolator.getInterpolation(ratio); } else { // since we can't use the path interpolator here, just interpolate linearly instead bezierOutput = ratio; } float scale = (minimumSize + (maximumHeaderTextSize - minimumSize) * bezierOutput) / maximumHeaderTextSize; // Clamp to reasonable/finite values before passing into framework. The values // can be wacky before the first pre-render. bezierOutput = Math.min(bezierOutput, 1.0f); scale = Math.min(scale, 1.0f); largeTextView.setScaleX(scale); largeTextView.setScaleY(scale); setInterpolatedTitleMargins(bezierOutput); } /** * Update the FAB visibility state depending on toolbar height. */ private void updateFabStatus() { if (enableFab) { if (getToolbarHeight() >= intermediateHeaderHeight) { if (!fab.isShown()) { fab.show(); } } else { if (fab.isShown()) { fab.hide(); } } } } /** * Update the FAB visibility state depending on scrollview state. * * @param scrollY the y value of the scroll. */ private void updateFabStatus(int scrollY) { if (enableFab) { if (scrollY < scrollView.getMeasuredHeight() / 10) { if (!fab.isShown()) { fab.show(); } } else { if (fab.isShown()) { fab.hide(); } } } } /** * Set whether or not the FAB should be displayed. * * @param enableFab whether to enable the fab. */ public void setEnableFab(boolean enableFab) { this.enableFab = enableFab; if (!enableFab) { fab.hide(); } } /** * Calculate the padding around largeTextView so that it will look appropriate once it * finishes moving into its target location/size. */ private void calculateCollapsedLargeTitlePadding() { collapsedTitleBottomMargin = (minimumHeaderHeight - largeTextView.getMeasuredHeight()) / 2; } /** * Interpolate the title's margin size. When {@param x}=1, use the maximum title margins. * When {@param x}=0, use the margin values taken from {@link #invisiblePlaceholderTextView}. */ private void setInterpolatedTitleMargins(float x) { final LayoutParams titleLayoutParams = (LayoutParams) largeTextView.getLayoutParams(); final ViewGroup.LayoutParams toolbarLayoutParams = toolbar.getLayoutParams(); // Need to add more to margin start if there is a start column int startColumnWidth = startColumn == null ? 0 : startColumn.getWidth(); if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) { titleLayoutParams.setMarginStart( (int) (collapsedTitleStartMargin * (1 - x) + maximumTitleMargin * x) + startColumnWidth); } // How offset the title should be from the bottom of the toolbar final int pretendBottomMargin = (int) (collapsedTitleBottomMargin * (1 - x) + maximumTitleMargin * x); // Calculate how offset the title should be from the top of the screen. Instead of // calling largeTextView.getHeight() use the maximumHeaderTextSize for this calculation. // The getHeight() value acts unexpectedly when largeTextView is partially clipped by // its parent. titleLayoutParams.topMargin = getTransparentViewHeight() + toolbarLayoutParams.height - pretendBottomMargin - maximumHeaderTextSize; titleLayoutParams.bottomMargin = 0; largeTextView.setLayoutParams(titleLayoutParams); } private void updatePhotoTintAndDropShadow() { // We need to use toolbarLayoutParams to determine the height, since the layout // params can be updated before the height change is reflected inside the View#getHeight(). final int toolbarHeight = getToolbarHeight(); if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { if (toolbarHeight <= minimumHeaderHeight && !isTwoPanel) { photoViewContainer.setElevation(toolbarElevation); } else { photoViewContainer.setElevation(0); } } final int gradientAlpha; final float colorAlpha; if (isTwoPanel) { colorAlpha = 0; gradientAlpha = 0x44; } else { float ratio = ((toolbarHeight - minimumHeaderHeight) / (float) (maximumHeaderHeight - minimumHeaderHeight)); if (toolbarHeight >= maximumHeaderHeight) { colorAlpha = 0; } else if (toolbarHeight >= intermediateHeaderHeight && toolbarHeight < maximumHeaderHeight) { colorAlpha = (-0.25f * ratio) + .25f; } else { colorAlpha = (-1.5f * ratio) + 1; } gradientAlpha = 0; } // Tell the photo view what tint we are trying to achieve. Depending on the type of // drawable used, the photo view may or may not use this tint. photoView.setBackgroundColor(headerTintColor); photoTouchInterceptOverlay.setBackgroundColor(ColorUtils.adjustAlpha(headerTintColor, colorAlpha)); titleGradientDrawable.setAlpha(gradientAlpha); actionBarGradientDrawable.setAlpha(gradientAlpha); } private void updateLastEventPosition(MotionEvent event) { lastEventPosition[0] = event.getX(); lastEventPosition[1] = event.getY(); } private boolean motionShouldStartDrag(MotionEvent event) { final float deltaY = event.getY() - lastEventPosition[1]; return deltaY > touchSlop || deltaY < -touchSlop; } private float updatePositionAndComputeDelta(MotionEvent event) { final int VERTICAL = 1; final float position = lastEventPosition[VERTICAL]; updateLastEventPosition(event); float elasticityFactor = 1; if (position < lastEventPosition[VERTICAL] && hasEverTouchedTheTop) { // As QuickContacts is dragged from the top of the window, its rate of movement will // slow down in proportion to its distance from the top. This will feel springy. elasticityFactor += transparentView.getHeight() * SPRING_DAMPENING_FACTOR; } return (position - lastEventPosition[VERTICAL]) / elasticityFactor; } private void smoothScrollBy(int delta) { if (delta == 0) { // Delta=0 implies the code calling smoothScrollBy is sloppy. We should avoid doing // this, since it prevents Views from being able to register any clicks for 250ms. throw new IllegalArgumentException("Smooth scrolling by delta=0 is " + "pointless and harmful"); } scroller.startScroll(0, getScroll(), 0, delta); invalidate(); } /** * Interpolator that enforces a specific starting velocity. This is useful to avoid a * discontinuity between dragging speed and flinging speed. * <p> * Similar to a {@link android.view.animation.AccelerateInterpolator} in the sense that * getInterpolation() is a quadratic function. */ private static class AcceleratingFlingInterpolator implements Interpolator { private final float startingSpeedPixelsPerFrame; private final float durationMs; private final int pixelsDelta; private final float numberFrames; public AcceleratingFlingInterpolator(int durationMs, float startingSpeedPixelsPerSecond, int pixelsDelta) { startingSpeedPixelsPerFrame = startingSpeedPixelsPerSecond / getRefreshRate(); this.durationMs = durationMs; this.pixelsDelta = pixelsDelta; numberFrames = this.durationMs / getFrameIntervalMs(); } @Override public float getInterpolation(float input) { final float animationIntervalNumber = numberFrames * input; final float linearDelta = (animationIntervalNumber * startingSpeedPixelsPerFrame) / pixelsDelta; // Add the results of a linear interpolator (with the initial speed) with the // results of a AccelerateInterpolator. if (startingSpeedPixelsPerFrame > 0) { return Math.min(input * input + linearDelta, 1); } else { // Initial fling was in the wrong direction, make sure that the quadratic component // grows faster in order to make up for this. return Math.min(input * (input - linearDelta) + linearDelta, 1); } } private float getRefreshRate() { // TODO // DisplayInfo di = DisplayManagerGlobal.getInstance().getDisplayInfo( // Display.DEFAULT_DISPLAY); // return di.refreshRate; return 30f; } public long getFrameIntervalMs() { return (long) (1000 / getRefreshRate()); } } }