仿鲜果联播的view

近来换了份工作，做了几个UI，需求不是很明确，任由我发挥，有类似view添加删除的功能，很自然地想到了做一个类似鲜果的View，ubuntu下用

byzanz-record -d 60 -x 70 -y 30 -w 1280 -h 720 byzanz-demo.gif   截图的，第一次截。记录下吧。

（这样截出来的gif不知道为什么cdns显示不出来，唉，截张图吧，大致就是这个效果，感谢这篇博文http://blog.csdn.net/xiaanming/article/details/17718579，我主要就添加了数据的保存及删除操作，点击事件的捕获。）

后来看到评论开源项目https://github.com/mrKlar/PagedDragDropGrid这个也不错啊

新工作大老板说得天花乱坠，现在差不多快一个月了，感觉被忽悠了 ，哎，心开始又乱了。。。记录下吧，改了下SystemUI，添加了些基本按钮，为了实现点击显示原launcher显示所有app的view，于是，感谢然后写了个apk模仿了下，PagedView.java这个开源类不错啊，一下就弄好了，我只是加了换页监听。

DVD，原厂蓝牙主要是通过socket向底层发送指令，因为蜂鸟系统底层做了定制，所以我要做的只是显示一个定制的视频类控件，然后发送指令。

截些图纪念下，

这个系统设置的view，美工如此设计，我... 好像不是很实用啊。。。。

指针可以旋转的view，可以参考  http://www.eoeandroid.com/forum.php?mod=viewthread&tid=71484

仿鲜果联播的view代码

package com.isunicom.isunallapp;import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.util.AttributeSet;
import android.util.Log;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.view.accessibility.AccessibilityEvent;
import android.view.accessibility.AccessibilityManager;
import android.view.animation.AccelerateInterpolator;
import android.view.animation.DecelerateInterpolator;
import android.view.animation.Interpolator;
import android.widget.Scroller;import java.util.ArrayList;public class PagedView extends ViewGroup {private static final int SCREEN_SCROLLED_MIN_VERSION = 11;private static float TRANSITION_SCALE_FACTOR = 0.74f;private AccelerateInterpolator mAlphaInterpolator = new AccelerateInterpolator(0.9f);private DecelerateInterpolator mLeftScreenAlphaInterpolator = new DecelerateInterpolator(4);private static final boolean PERFORM_OVERSCROLL_ROTATION = true;private static float CAMERA_DISTANCE = 6500;private static float TRANSITION_PIVOT = 0.65f;private static float TRANSITION_MAX_ROTATION = 22;protected static final int INVALID_PAGE = -1;// the min drag distance for a fling to register, to prevent random page// shiftsprivate static final int MIN_LENGTH_FOR_FLING = 25;protected static final int PAGE_SNAP_ANIMATION_DURATION = 550;protected static final int SLOW_PAGE_SNAP_ANIMATION_DURATION = 950;protected static final float NANOTIME_DIV = 1000000000.0f;private static final float OVERSCROLL_ACCELERATE_FACTOR = 2;private static final float RETURN_TO_ORIGINAL_PAGE_THRESHOLD = 0.33f;// The page is moved more than halfway, automatically move to the next page// on touch up.private static final float SIGNIFICANT_MOVE_THRESHOLD = 0.4f;// The following constants need to be scaled based on density. The scaled// versions will be// assigned to the corresponding member variables below.private static final int FLING_THRESHOLD_VELOCITY = 500;private static final int MIN_SNAP_VELOCITY = 1500;private static final int MIN_FLING_VELOCITY = 250;static final int AUTOMATIC_PAGE_SPACING = -1;protected int mFlingThresholdVelocity;protected int mMinFlingVelocity;protected int mMinSnapVelocity;protected float mDensity;protected float mSmoothingTime;protected float mTouchX;protected boolean mFirstLayout = true;protected int mCurrentPage;protected int mNextPage = INVALID_PAGE;protected int mMaxScrollX;protected Scroller mScroller;private VelocityTracker mVelocityTracker;private float mDownMotionX;protected float mLastMotionX;protected float mLastMotionXRemainder;protected float mLastMotionY;protected float mTotalMotionX;private int mLastScreenCenter = -1;private int[] mChildOffsets;private int[] mChildRelativeOffsets;private int[] mChildOffsetsWithLayoutScale;protected final static int TOUCH_STATE_REST = 0;protected final static int TOUCH_STATE_SCROLLING = 1;protected final static int TOUCH_STATE_PREV_PAGE = 2;protected final static int TOUCH_STATE_NEXT_PAGE = 3;protected final static float ALPHA_QUANTIZE_LEVEL = 0.0001f;protected int mTouchState = TOUCH_STATE_REST;protected boolean mForceScreenScrolled = false;protected int mTouchSlop;private int mPagingTouchSlop;private int mMaximumVelocity;protected int mPageSpacing;protected int mPageLayoutPaddingTop;protected int mPageLayoutPaddingBottom;protected int mPageLayoutPaddingLeft;protected int mPageLayoutPaddingRight;protected int mPageLayoutWidthGap;protected int mPageLayoutHeightGap;protected int mCellCountX = 0;protected int mCellCountY = 0;protected boolean mCenterPagesVertically;protected boolean mAllowOverScroll = true;protected int mUnboundedScrollX;protected int[] mTempVisiblePagesRange = new int[2];protected boolean mForceDrawAllChildrenNextFrame;// mOverScrollX is equal to getScrollX() when we're within the normal scroll// range. Otherwise// it is equal to the scaled overscroll position. We use a separate value so// as to prevent// the screens from continuing to translate beyond the normal bounds.protected int mOverScrollX;// parameter that adjusts the layout to be optimized for pages with that// scale factorprotected float mLayoutScale = 1.0f;protected static final int INVALID_POINTER = -1;protected int mActivePointerId = INVALID_POINTER;protected ArrayList<Boolean> mDirtyPageContent;// If true, syncPages and syncPageItems will be called to refresh pagesprotected boolean mContentIsRefreshable = true;// If true, modify alpha of neighboring pages as user scrolls left/rightprotected boolean mFadeInAdjacentScreens = true;// It true, use a different slop parameter (pagingTouchSlop = 2 * touchSlop)// for deciding// to switch to a new pageprotected boolean mUsePagingTouchSlop = true;// If true, the subclass should directly update scrollX itself in its// computeScroll method// (SmoothPagedView does this)protected boolean mDeferScrollUpdate = false;protected boolean mIsPageMoving = false;// All syncs and layout passes are deferred until data is ready.protected boolean mIsDataReady = false;// If set, will defer loading associated pages until the scrolling settles// Begin Immersion changesprotected boolean mHapticFlingStarted = false;protected boolean mHapticCaptureFling = true;protected int mLastHapticScreen = 0;ZInterpolator mZInterpolator = new ZInterpolator(0.5f);// End Immersion changespublic PagedView(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);init();}public PagedView(Context context, AttributeSet attrs) {this(context, attrs, 0);}public PagedView(Context context) {this(context, null);}@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {final int widthMode = MeasureSpec.getMode(widthMeasureSpec);final int widthSize = MeasureSpec.getSize(widthMeasureSpec);final int heightMode = MeasureSpec.getMode(heightMeasureSpec);int heightSize = MeasureSpec.getSize(heightMeasureSpec);if (widthMode != MeasureSpec.EXACTLY) {throw new IllegalStateException("Workspace can only be used in EXACTLY mode.");}// Return early if we aren't given a proper dimensionif (widthSize <= 0 || heightSize <= 0) {super.onMeasure(widthMeasureSpec, heightMeasureSpec);return;}/** Allow the height to be set as WRAP_CONTENT. This allows the* particular case of the All apps view on XLarge displays to not take* up more space then it needs. Width is still not allowed to be set as* WRAP_CONTENT since many parts of the code expect each page to have* the same width.*/int maxChildHeight = 0;final int verticalPadding = getPaddingTop() + getPaddingBottom();final int horizontalPadding = getPaddingLeft() + getPaddingRight();// The children are given the same width and height as the workspace// unless they were set to WRAP_CONTENTfinal int childCount = getChildCount();for (int i = 0; i < childCount; i++) {// disallowing padding in paged view (just pass 0)final View child = getPageAt(i);final LayoutParams lp = (LayoutParams) child.getLayoutParams();int childWidthMode;if (lp.width == LayoutParams.WRAP_CONTENT) {childWidthMode = MeasureSpec.AT_MOST;} else {childWidthMode = MeasureSpec.EXACTLY;}int childHeightMode;if (lp.height == LayoutParams.WRAP_CONTENT) {childHeightMode = MeasureSpec.AT_MOST;} else {childHeightMode = MeasureSpec.EXACTLY;}final int childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(widthSize - horizontalPadding, childWidthMode);final int childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(heightSize - verticalPadding, childHeightMode);child.measure(childWidthMeasureSpec, childHeightMeasureSpec);maxChildHeight = Math.max(maxChildHeight, child.getMeasuredHeight());}if (heightMode == MeasureSpec.AT_MOST) {heightSize = maxChildHeight + verticalPadding;}setMeasuredDimension(widthSize, heightSize);// We can't call getChildOffset/getRelativeChildOffset until we set the// measured dimensions.// We also wait until we set the measured dimensions before flushing the// cache as well, to// ensure that the cache is filled with good values.invalidateCachedOffsets();if (childCount > 0) {// Calculate the variable page spacing if necessaryif (mPageSpacing == AUTOMATIC_PAGE_SPACING) {// The gap between pages in the PagedView should be equal to the// gap from the page// to the edge of the screen (so it is not visible in the// current screen). To// account for unequal padding on each side of the paged view,// we take the maximum// of the left/right gap and use that as the gap between each// page.int offset = getRelativeChildOffset(0);int spacing = Math.max(offset,widthSize - offset - getChildAt(0).getMeasuredWidth());setPageSpacing(spacing);}}if (childCount > 0) {mMaxScrollX = getChildOffset(childCount - 1)- getRelativeChildOffset(childCount - 1);} else {mMaxScrollX = 0;}}@Overrideprotected void onLayout(boolean changed, int l, int t, int r, int b) {final int verticalPadding = getPaddingTop() + getPaddingBottom();final int childCount = getChildCount();int childLeft = getRelativeChildOffset(0);for (int i = 0; i < childCount; i++) {final View child = getPageAt(i);if (child.getVisibility() != View.GONE) {final int childWidth = getScaledMeasuredWidth(child);final int childHeight = child.getMeasuredHeight();int childTop = getPaddingTop();if (mCenterPagesVertically) {childTop += ((getMeasuredHeight() - verticalPadding) - childHeight) / 2;}child.layout(childLeft, childTop,childLeft + child.getMeasuredWidth(), childTop+ childHeight);childLeft += childWidth + mPageSpacing;}}if (mFirstLayout && mCurrentPage >= 0 && mCurrentPage < getChildCount()) {updateCurrentPageScroll();mFirstLayout = false;}}View getPageAt(int index) {return getChildAt(index);}public int getmCurrentPage() {return mCurrentPage;}protected int getChildWidth(int index) {final int measuredWidth = getPageAt(index).getMeasuredWidth();return measuredWidth;}protected int getScaledMeasuredWidth(View child) {final int measuredWidth = child.getMeasuredWidth();final int minWidth = 0;final int maxWidth = (minWidth > measuredWidth) ? minWidth: measuredWidth;return (int) (maxWidth * mLayoutScale + 0.5f);}protected void updateCurrentPageScroll() {int offset = getChildOffset(mCurrentPage);int relOffset = getRelativeChildOffset(mCurrentPage);int newX = offset - relOffset;scrollTo(newX, 0);mScroller.setFinalX(newX);mScroller.forceFinished(true);}protected int getChildOffset(int index) {int[] childOffsets = Float.compare(mLayoutScale, 1f) == 0 ? mChildOffsets: mChildOffsetsWithLayoutScale;if (childOffsets != null && childOffsets[index] != -1) {return childOffsets[index];} else {if (getChildCount() == 0)return 0;int offset = getRelativeChildOffset(0);for (int i = 0; i < index; ++i) {offset += getScaledMeasuredWidth(getPageAt(i)) + mPageSpacing;}if (childOffsets != null) {childOffsets[index] = offset;}return offset;}}protected int getRelativeChildOffset(int index) {if (mChildRelativeOffsets != null && mChildRelativeOffsets[index] != -1) {return mChildRelativeOffsets[index];} else {final int padding = getPaddingLeft() + getPaddingRight();final int offset = getPaddingLeft()+ (getMeasuredWidth() - padding - getChildWidth(index)) / 2;if (mChildRelativeOffsets != null) {mChildRelativeOffsets[index] = offset;}return offset;}}public void setPageSpacing(int pageSpacing) {mPageSpacing = pageSpacing;invalidateCachedOffsets();}protected void invalidateCachedOffsets() {int count = getChildCount();if (count == 0) {mChildOffsets = null;mChildRelativeOffsets = null;mChildOffsetsWithLayoutScale = null;return;}mChildOffsets = new int[count];mChildRelativeOffsets = new int[count];mChildOffsetsWithLayoutScale = new int[count];for (int i = 0; i < count; i++) {mChildOffsets[i] = -1;mChildRelativeOffsets[i] = -1;mChildOffsetsWithLayoutScale[i] = -1;}}protected void init() {mDirtyPageContent = new ArrayList<Boolean>();mDirtyPageContent.ensureCapacity(32);mScroller = new Scroller(getContext(), new ScrollInterpolator());mCurrentPage = 0;mCenterPagesVertically = true;final ViewConfiguration configuration = ViewConfiguration.get(getContext());mTouchSlop = configuration.getScaledTouchSlop();mPagingTouchSlop = configuration.getScaledPagingTouchSlop();mMaximumVelocity = configuration.getScaledMaximumFlingVelocity();mDensity = getResources().getDisplayMetrics().density;mFlingThresholdVelocity = (int) (FLING_THRESHOLD_VELOCITY * mDensity);mMinFlingVelocity = (int) (MIN_FLING_VELOCITY * mDensity);mMinSnapVelocity = (int) (MIN_SNAP_VELOCITY * mDensity);}private static class ScrollInterpolator implements Interpolator {public ScrollInterpolator() {}public float getInterpolation(float t) {t -= 1.0f;return t * t * t * t * t + 1;}}@Overridepublic boolean onInterceptTouchEvent(MotionEvent ev) {/** This method JUST determines whether we want to intercept the motion.* If we return true, onTouchEvent will be called and we do the actual* scrolling there.*/acquireVelocityTrackerAndAddMovement(ev);// Skip touch handling if there are no pages to swipeif (getChildCount() <= 0)return super.onInterceptTouchEvent(ev);/** Shortcut the most recurring case: the user is in the dragging state* and he is moving his finger. We want to intercept this motion.*/final int action = ev.getAction();if ((action == MotionEvent.ACTION_MOVE)&& (mTouchState == TOUCH_STATE_SCROLLING)) {return true;}switch (action & MotionEvent.ACTION_MASK) {case MotionEvent.ACTION_MOVE: {/** mIsBeingDragged == false, otherwise the shortcut would have* caught it. Check whether the user has moved far enough from his* original down touch.*/if (mActivePointerId != INVALID_POINTER) {determineScrollingStart(ev);break;}// if mActivePointerId is INVALID_POINTER, then we must have missed// an ACTION_DOWN// event. in that case, treat the first occurence of a move event as// a ACTION_DOWN// i.e. fall through to the next case (don't break)// (We sometimes miss ACTION_DOWN events in Workspace because it// ignores all events// while it's small- this was causing a crash before we checked for// INVALID_POINTER)}case MotionEvent.ACTION_DOWN: {final float x = ev.getX();final float y = ev.getY();// Remember location of down touchmDownMotionX = x;mLastMotionX = x;mLastMotionY = y;mLastMotionXRemainder = 0;mTotalMotionX = 0;mActivePointerId = ev.getPointerId(0);/** If being flinged and user touches the screen, initiate drag;* otherwise don't. mScroller.isFinished should be false when being* flinged.*/final int xDist = Math.abs(mScroller.getFinalX()- mScroller.getCurrX());final boolean finishedScrolling = (mScroller.isFinished() || xDist < mTouchSlop);if (finishedScrolling) {mTouchState = TOUCH_STATE_REST;mScroller.abortAnimation();} else {mTouchState = TOUCH_STATE_SCROLLING;}// check if this can be the beginning of a tap on the side of the// pages// to scroll the current pageif (mTouchState != TOUCH_STATE_PREV_PAGE&& mTouchState != TOUCH_STATE_NEXT_PAGE) {if (getChildCount() > 0) {if (hitsPreviousPage(x, y)) {mTouchState = TOUCH_STATE_PREV_PAGE;} else if (hitsNextPage(x, y)) {mTouchState = TOUCH_STATE_NEXT_PAGE;}}}break;}case MotionEvent.ACTION_UP:case MotionEvent.ACTION_CANCEL:mTouchState = TOUCH_STATE_REST;mActivePointerId = INVALID_POINTER;releaseVelocityTracker();break;case MotionEvent.ACTION_POINTER_UP:onSecondaryPointerUp(ev);releaseVelocityTracker();break;}/** The only time we want to intercept motion events is if we are in the* drag mode.*/return mTouchState != TOUCH_STATE_REST;}protected boolean hitsPreviousPage(float x, float y) {return (x < getRelativeChildOffset(mCurrentPage) - mPageSpacing);}protected boolean hitsNextPage(float x, float y) {return (x > (getMeasuredWidth() - getRelativeChildOffset(mCurrentPage) + mPageSpacing));}@Overridepublic boolean onTouchEvent(MotionEvent ev) {if (getChildCount() <= 0)return super.onTouchEvent(ev);acquireVelocityTrackerAndAddMovement(ev);final int action = ev.getAction();switch (action & MotionEvent.ACTION_MASK) {case MotionEvent.ACTION_DOWN:/** If being flinged and user touches, stop the fling. isFinished* will be false if being flinged.*/if (!mScroller.isFinished()) {mScroller.abortAnimation();}// Remember where the motion event startedmDownMotionX = mLastMotionX = ev.getX();mLastMotionXRemainder = 0;mTotalMotionX = 0;mActivePointerId = ev.getPointerId(0);if (mTouchState == TOUCH_STATE_SCROLLING) {pageBeginMoving();}break;case MotionEvent.ACTION_MOVE:if (mTouchState == TOUCH_STATE_SCROLLING) {// Scroll to follow the motion eventfinal int pointerIndex = ev.findPointerIndex(mActivePointerId);final float x = ev.getX(pointerIndex);final float deltaX = mLastMotionX + mLastMotionXRemainder - x;mTotalMotionX += Math.abs(deltaX);// Only scroll and update mLastMotionX if we have moved some// discrete amount. We// keep the remainder because we are actually testing if we've// moved from the last// scrolled position (which is discrete).if (Math.abs(deltaX) >= 1.0f) {mTouchX += deltaX;mSmoothingTime = System.nanoTime() / NANOTIME_DIV;if (!mDeferScrollUpdate) {scrollBy((int) deltaX, 0);} else {invalidate();}mLastMotionX = x;mLastMotionXRemainder = deltaX - (int) deltaX;} else {awakenScrollBars();}} else {determineScrollingStart(ev);}break;case MotionEvent.ACTION_UP:if (mTouchState == TOUCH_STATE_SCROLLING) {final int activePointerId = mActivePointerId;final int pointerIndex = ev.findPointerIndex(activePointerId);final float x = ev.getX(pointerIndex);final VelocityTracker velocityTracker = mVelocityTracker;velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);int velocityX = (int) velocityTracker.getXVelocity(activePointerId);final int deltaX = (int) (x - mDownMotionX);final int pageWidth = getScaledMeasuredWidth(getPageAt(mCurrentPage));boolean isSignificantMove = Math.abs(deltaX) > pageWidth* SIGNIFICANT_MOVE_THRESHOLD;mTotalMotionX += Math.abs(mLastMotionX + mLastMotionXRemainder- x);boolean isFling = mTotalMotionX > MIN_LENGTH_FOR_FLING&& Math.abs(velocityX) > mFlingThresholdVelocity;// In the case that the page is moved far to one direction and// then is flung// in the opposite direction, we use a threshold to determine// whether we should// just return to the starting page, or if we should skip one// further.boolean returnToOriginalPage = false;if (Math.abs(deltaX) > pageWidth* RETURN_TO_ORIGINAL_PAGE_THRESHOLD&& Math.signum(velocityX) != Math.signum(deltaX)&& isFling) {returnToOriginalPage = true;}int finalPage = 0;// We give flings precedence over large moves, which is why we// short-circuit our// test for a large move if a fling has been registered. That// is, a large// move to the left and fling to the right will register as a// fling to the right.if (((isSignificantMove && deltaX > 0 && !isFling) || (isFling && velocityX > 0))&& mCurrentPage > 0) {finalPage = returnToOriginalPage ? mCurrentPage: mCurrentPage - 1;snapToPageWithVelocity(finalPage, velocityX);} else if (((isSignificantMove && deltaX < 0 && !isFling) || (isFling && velocityX < 0))&& mCurrentPage < getChildCount() - 1) {finalPage = returnToOriginalPage ? mCurrentPage: mCurrentPage + 1;snapToPageWithVelocity(finalPage, velocityX);} else {snapToDestination();}} else if (mTouchState == TOUCH_STATE_PREV_PAGE) {// at this point we have not moved beyond the touch slop// (otherwise mTouchState would be TOUCH_STATE_SCROLLING), so// we can just pageint nextPage = Math.max(0, mCurrentPage - 1);if (nextPage != mCurrentPage) {snapToPage(nextPage);} else {snapToDestination();}} else if (mTouchState == TOUCH_STATE_NEXT_PAGE) {// at this point we have not moved beyond the touch slop// (otherwise mTouchState would be TOUCH_STATE_SCROLLING), so// we can just pageint nextPage = Math.min(getChildCount() - 1, mCurrentPage + 1);if (nextPage != mCurrentPage) {snapToPage(nextPage);} else {snapToDestination();}}mTouchState = TOUCH_STATE_REST;mActivePointerId = INVALID_POINTER;releaseVelocityTracker();break;case MotionEvent.ACTION_CANCEL:if (mTouchState == TOUCH_STATE_SCROLLING) {snapToDestination();}mTouchState = TOUCH_STATE_REST;mActivePointerId = INVALID_POINTER;releaseVelocityTracker();break;case MotionEvent.ACTION_POINTER_UP:onSecondaryPointerUp(ev);break;}return true;}@Overridepublic boolean onGenericMotionEvent(MotionEvent event) {// TODO if (event.getSource()!= 0) {switch (event.getAction()) {case MotionEvent.ACTION_SCROLL: {// Handle mouse (or ext. device) by shifting the page depending// on the scrollfinal float vscroll;final float hscroll;if ((event.getMetaState() & KeyEvent.META_SHIFT_ON) != 0) {vscroll = 0;hscroll = event.getAxisValue(MotionEvent.AXIS_VSCROLL);} else {vscroll = -event.getAxisValue(MotionEvent.AXIS_VSCROLL);hscroll = event.getAxisValue(MotionEvent.AXIS_HSCROLL);}if (hscroll != 0 || vscroll != 0) {if (hscroll > 0 || vscroll > 0) {scrollRight();} else {scrollLeft();}return true;}}}}return super.onGenericMotionEvent(event);}private void acquireVelocityTrackerAndAddMovement(MotionEvent ev) {if (mVelocityTracker == null) {mVelocityTracker = VelocityTracker.obtain();}mVelocityTracker.addMovement(ev);}private void releaseVelocityTracker() {if (mVelocityTracker != null) {mVelocityTracker.recycle();mVelocityTracker = null;}}protected void pageBeginMoving() {if (!mIsPageMoving) {mIsPageMoving = true;onPageBeginMoving();}}protected void pageEndMoving() {if (mIsPageMoving) {mIsPageMoving = false;onPageEndMoving();}}protected boolean isPageMoving() {return mIsPageMoving;}// a method that subclasses can override to add behaviorprotected void onPageBeginMoving() {// Begin Immersion changesif (mHapticCaptureFling && mNextPage != mCurrentPage) {if (!mHapticFlingStarted) {mHapticFlingStarted = true;mLastHapticScreen = mCurrentPage;} else {if ((mNextPage != INVALID_PAGE)&& (mLastHapticScreen != mNextPage)) {}mHapticFlingStarted = false;}}// End Immersion changes}// a method that subclasses can override to add behaviorprotected void onPageEndMoving() {// Reset the FlagsmHapticCaptureFling = true;mHapticFlingStarted = false;// End Immersion changesmForceDrawAllChildrenNextFrame = true;}protected void determineScrollingStart(MotionEvent ev) {determineScrollingStart(ev, 1.0f);}/** Determines if we should change the touch state to start scrolling after* the user moves their touch point too far.*/protected void determineScrollingStart(MotionEvent ev, float touchSlopScale) {/** Locally do absolute value. mLastMotionX is set to the y value of the* down event.*/final int pointerIndex = ev.findPointerIndex(mActivePointerId);if (pointerIndex == -1) {return;}final float x = ev.getX(pointerIndex);final float y = ev.getY(pointerIndex);final int xDiff = (int) Math.abs(x - mLastMotionX);final int yDiff = (int) Math.abs(y - mLastMotionY);final int touchSlop = Math.round(touchSlopScale * mTouchSlop);boolean xPaged = xDiff > mPagingTouchSlop;boolean xMoved = xDiff > touchSlop;boolean yMoved = yDiff > touchSlop;if (xMoved || xPaged || yMoved) {if (mUsePagingTouchSlop ? xPaged : xMoved) {// Scroll if the user moved far enough along the X axismTouchState = TOUCH_STATE_SCROLLING;mTotalMotionX += Math.abs(mLastMotionX - x);mLastMotionX = x;mLastMotionXRemainder = 0;mTouchX = getScrollX();mSmoothingTime = System.nanoTime() / NANOTIME_DIV;pageBeginMoving();}}}protected void snapToPageWithVelocity(int whichPage, int velocity) {whichPage = Math.max(0, Math.min(whichPage, getChildCount() - 1));int halfScreenSize = getMeasuredWidth() / 2;final int newX = getChildOffset(whichPage)- getRelativeChildOffset(whichPage);int delta = newX - mUnboundedScrollX;int duration = 0;if (Math.abs(velocity) < mMinFlingVelocity) {// If the velocity is low enough, then treat this more as an// automatic page advance// as opposed to an apparent physical response to flingingsnapToPage(whichPage, PAGE_SNAP_ANIMATION_DURATION);return;}// Here we compute a "distance" that will be used in the computation of// the overall// snap duration. This is a function of the actual distance that needs// to be traveled;// we keep this value close to half screen size in order to reduce the// variance in snap// duration as a function of the distance the page needs to travel.float distanceRatio = Math.min(1f, 1.0f * Math.abs(delta)/ (2 * halfScreenSize));float distance = halfScreenSize + halfScreenSize* distanceInfluenceForSnapDuration(distanceRatio);velocity = Math.abs(velocity);velocity = Math.max(mMinSnapVelocity, velocity);// we want the page's snap velocity to approximately match the velocity// at which the// user flings, so we scale the duration by a value near to the// derivative of the scroll// interpolator at zero, ie. 5. We use 4 to make it a little slower.duration = 4 * Math.round(1000 * Math.abs(distance / velocity));snapToPage(whichPage, delta, duration);}protected void snapToPage(int whichPage) {snapToPage(whichPage, PAGE_SNAP_ANIMATION_DURATION);}protected void snapToPage(int whichPage, int duration) {whichPage = Math.max(0, Math.min(whichPage, getPageCount() - 1));int newX = getChildOffset(whichPage)- getRelativeChildOffset(whichPage);final int sX = mUnboundedScrollX;final int delta = newX - sX;snapToPage(whichPage, delta, duration);}protected void snapToPage(int whichPage, int delta, int duration) {mNextPage = whichPage;//wufenonScreenChangeListener.onScreenChange(mNextPage);View focusedChild = getFocusedChild();if (focusedChild != null && whichPage != mCurrentPage&& focusedChild == getPageAt(mCurrentPage)) {focusedChild.clearFocus();}pageBeginMoving();awakenScrollBars(duration);if (duration == 0) {duration = Math.abs(delta);}if (!mScroller.isFinished())mScroller.abortAnimation();mScroller.startScroll(mUnboundedScrollX, 0, delta, 0, duration);// Load associated pages immediately if someone else is handling the// scroll, otherwise defer// loading associated pages until the scroll settlesinvalidate();}public void scrollLeft() {if (mScroller.isFinished()) {if (mCurrentPage > 0)snapToPage(mCurrentPage - 1);} else {if (mNextPage > 0)snapToPage(mNextPage - 1);}}public void scrollRight() {if (mScroller.isFinished()) {if (mCurrentPage < getChildCount() - 1)snapToPage(mCurrentPage + 1);} else {if (mNextPage < getChildCount() - 1)snapToPage(mNextPage + 1);}}protected void snapToDestination() {snapToPage(getPageNearestToCenterOfScreen(),PAGE_SNAP_ANIMATION_DURATION);}private void onSecondaryPointerUp(MotionEvent ev) {final int pointerIndex = (ev.getAction() & MotionEvent.ACTION_POINTER_INDEX_MASK) >> MotionEvent.ACTION_POINTER_INDEX_SHIFT;final int pointerId = ev.getPointerId(pointerIndex);if (pointerId == mActivePointerId) {// This was our active pointer going up. Choose a new// active pointer and adjust accordingly.// TODO: Make this decision more intelligent.final int newPointerIndex = pointerIndex == 0 ? 1 : 0;mLastMotionX = mDownMotionX = ev.getX(newPointerIndex);mLastMotionY = ev.getY(newPointerIndex);mLastMotionXRemainder = 0;mActivePointerId = ev.getPointerId(newPointerIndex);if (mVelocityTracker != null) {mVelocityTracker.clear();}}}float distanceInfluenceForSnapDuration(float f) {f -= 0.5f; // center the values about 0.f *= 0.3f * Math.PI / 2.0f;return (float) Math.sin(f);}protected int getPageCount() {return getChildCount();}protected int getPageNearestToCenterOfScreen() {int minDistanceFromScreenCenter = Integer.MAX_VALUE;int minDistanceFromScreenCenterIndex = -1;int screenCenter = getScrollX() + (getMeasuredWidth() / 2);final int childCount = getChildCount();for (int i = 0; i < childCount; ++i) {View layout = (View) getPageAt(i);int childWidth = getScaledMeasuredWidth(layout);int halfChildWidth = (childWidth / 2);int childCenter = getChildOffset(i) + halfChildWidth;int distanceFromScreenCenter = Math.abs(childCenter - screenCenter);if (distanceFromScreenCenter < minDistanceFromScreenCenter) {minDistanceFromScreenCenter = distanceFromScreenCenter;minDistanceFromScreenCenterIndex = i;}}return minDistanceFromScreenCenterIndex;}protected void dispatchDraw(Canvas canvas) {int halfScreenSize = getMeasuredWidth() / 2;// mOverScrollX is equal to getScrollX() when we're within the normal// scroll range.// Otherwise it is equal to the scaled overscroll position.int screenCenter = mOverScrollX + halfScreenSize;if (screenCenter != mLastScreenCenter || mForceScreenScrolled) {// set mForceScreenScrolled before calling screenScrolled so that// screenScrolled can// set it for the next framemForceScreenScrolled = false;screenScrolled(screenCenter);mLastScreenCenter = screenCenter;}// Find out which screens are visible; as an optimization we only call// draw on themfinal int pageCount = getChildCount();if (pageCount > 0) {getVisiblePages(mTempVisiblePagesRange);final int leftScreen = mTempVisiblePagesRange[0];final int rightScreen = mTempVisiblePagesRange[1];if (leftScreen != -1 && rightScreen != -1) {final long drawingTime = getDrawingTime();// Clip to the boundscanvas.save();canvas.clipRect(getScrollX(), getScrollY(), getScrollX()+ getRight() - getLeft(), getScrollY() + getBottom()- getTop());// On certain graphics drivers, if you draw to a off-screen// buffer that's not// used, it can lead to poor performance. We were running into// this when// setChildrenLayersEnabled was called on a CellLayout; that// triggered a re-draw// of that CellLayout's hardware layer, even if that CellLayout// wasn't visible.// As a fix, below we set pages that aren't going to be rendered// are to be// View.INVISIBLE, preventing re-drawing of their hardware layerfor (int i = getChildCount() - 1; i >= 0; i--) {final View v = getPageAt(i);if (mForceDrawAllChildrenNextFrame|| (leftScreen <= i && i <= rightScreen && shouldDrawChild(v))) {v.setVisibility(VISIBLE);drawChild(canvas, v, drawingTime);} else {v.setVisibility(INVISIBLE);}}mForceDrawAllChildrenNextFrame = false;canvas.restore();}}}protected void screenScrolled(int screenCenter) {for (int i = 0; i < getChildCount(); i++) {View v = getPageAt(i);if (v != null) {float scrollProgress = getScrollProgress(screenCenter, v, i);float interpolatedProgress = mZInterpolator.getInterpolation(Math.abs(Math.min(scrollProgress, 0)));float scale = (1 - interpolatedProgress) + interpolatedProgress* TRANSITION_SCALE_FACTOR;float translationX = Math.min(0, scrollProgress)* v.getMeasuredWidth();float alpha;if (scrollProgress < 0) {alpha = scrollProgress < 0 ? mAlphaInterpolator.getInterpolation(1 - Math.abs(scrollProgress)): 1.0f;if (i == 0) {setOverScrollAmount(v, Math.abs(scrollProgress));}} else {// On large screens we need to fade the page as it nears its// leftmost positionalpha = mLeftScreenAlphaInterpolator.getInterpolation(1 - scrollProgress);if (i == getChildCount() - 1) {setOverScrollAmount(v, Math.abs(scrollProgress));}}int pageWidth = v.getMeasuredWidth();int pageHeight = v.getMeasuredHeight();if (getVersion() >= SCREEN_SCROLLED_MIN_VERSION) {v.setCameraDistance(mDensity * CAMERA_DISTANCE);if (PERFORM_OVERSCROLL_ROTATION) {if (i == 0 && scrollProgress < 0) {// Overscroll to the leftv.setPivotX(TRANSITION_PIVOT * pageWidth);v.setRotationY(-TRANSITION_MAX_ROTATION* scrollProgress);scale = 1.0f;alpha = 1.0f;// On the first page, we don't want the page to have// any// lateral motiontranslationX = 0;} else if (i == getChildCount() - 1&& scrollProgress > 0) {// Overscroll to the rightv.setPivotX((1 - TRANSITION_PIVOT) * pageWidth);v.setRotationY(-TRANSITION_MAX_ROTATION* scrollProgress);scale = 1.0f;alpha = 1.0f;// On the last page, we don't want the page to have// any// lateral motion.translationX = 0;} else {v.setPivotY(pageHeight / 2.0f);v.setPivotX(pageWidth / 2.0f);v.setRotationY(0f);}}v.setTranslationX(translationX);v.setScaleX(scale);v.setScaleY(scale);
//                    v.setAlpha(alpha * 0.5f);v.setAlpha(alpha);   // if * 0.5f  it will to dark}// If the view has 0 alpha, we set it to be invisible so as to// prevent// it from accepting touchesif (alpha == 0) {v.setVisibility(INVISIBLE);} else if (v.getVisibility() != VISIBLE) {v.setVisibility(VISIBLE);}Log.d("Nevin","VERSION:"+getVersion());}}/* for (int i = 0; i < getChildCount(); i++) {View child = getChildAt(i);if (child != null) {float scrollProgress = getScrollProgress(screenCenter, child, i);float alpha = 1 - Math.abs(scrollProgress);child.setAlpha(alpha);}}invalidate();*/}public int getVersion() {try {int currentapiVersion=android.os.Build.VERSION.SDK_INT;return  currentapiVersion;} catch (Exception e) {e.printStackTrace();return 0;}}protected void setOverScrollAmount(View v, float r) {int alpha = (int) Math.round((r * 255));if (alpha != 0) {v.setBackgroundColor((int) Color.BLACK * ( - alpha));}v.invalidate();}protected void getVisiblePages(int[] range) {final int pageCount = getChildCount();if (pageCount > 0) {final int screenWidth = getMeasuredWidth();int leftScreen = 0;int rightScreen = 0;View currPage = getPageAt(leftScreen);while (leftScreen < pageCount - 1&& currPage.getLeft() + currPage.getWidth()- currPage.getPaddingRight() < getScrollX()) {leftScreen++;currPage = getPageAt(leftScreen);}rightScreen = leftScreen;currPage = getPageAt(rightScreen + 1);while (rightScreen < pageCount - 1&& currPage.getLeft() - currPage.getPaddingLeft() < getScrollX()+ screenWidth) {rightScreen++;currPage = getPageAt(rightScreen + 1);}range[0] = leftScreen;range[1] = rightScreen;} else {range[0] = -1;range[1] = -1;}}protected boolean shouldDrawChild(View child) {if (getVersion() >= SCREEN_SCROLLED_MIN_VERSION) {return child.getAlpha() > 0;}return true;}protected float getScrollProgress(int screenCenter, View v, int page) {final int halfScreenSize = getMeasuredWidth() / 2;int totalDistance = getScaledMeasuredWidth(v) + mPageSpacing;int delta = screenCenter- (getChildOffset(page) - getRelativeChildOffset(page) + halfScreenSize);float scrollProgress = delta / (totalDistance * 1.0f);scrollProgress = Math.min(scrollProgress, 1.0f);scrollProgress = Math.max(scrollProgress, -1.0f);return scrollProgress;}static class ZInterpolator implements TimeInterpolator {private float focalLength;public ZInterpolator(float foc) {focalLength = foc;}public float getInterpolation(float input) {return (1.0f - focalLength / (focalLength + input))/ (1.0f - focalLength / (focalLength + 1.0f));}}public interface TimeInterpolator {float getInterpolation(float input);}@Overridepublic void scrollBy(int x, int y) {scrollTo(mUnboundedScrollX + x, getScrollY() + y);}@Overridepublic void scrollTo(int x, int y) {mUnboundedScrollX = x;if (x < 0) {super.scrollTo(0, y);if (mAllowOverScroll) {overScroll(x);}} else if (x > mMaxScrollX) {super.scrollTo(mMaxScrollX, y);if (mAllowOverScroll) {overScroll(x - mMaxScrollX);}} else {mOverScrollX = x;super.scrollTo(x, y);}mTouchX = x;mSmoothingTime = System.nanoTime() / NANOTIME_DIV;}protected void overScroll(float amount) {acceleratedOverScroll(amount);}protected void acceleratedOverScroll(float amount) {int screenSize = getMeasuredWidth();// We want to reach the max over scroll effect when the user has// over scrolled half the size of the screenfloat f = OVERSCROLL_ACCELERATE_FACTOR * (amount / screenSize);if (f == 0)return;// Clamp this factor, f, to -1 < f < 1if (Math.abs(f) >= 1) {f /= Math.abs(f);}int overScrollAmount = (int) Math.round(f * screenSize);if (amount < 0) {mOverScrollX = overScrollAmount;super.scrollTo(0, getScrollY());} else {mOverScrollX = mMaxScrollX + overScrollAmount;super.scrollTo(mMaxScrollX, getScrollY());}invalidate();}protected boolean computeScrollHelper() {if (mScroller.computeScrollOffset()) {// Don't bother scrolling if the page does not need to be movedif (getScrollX() != mScroller.getCurrX()|| getScrollY() != mScroller.getCurrY()|| mOverScrollX != mScroller.getCurrX()) {scrollTo(mScroller.getCurrX(), mScroller.getCurrY());}invalidate();return true;} else if (mNextPage != INVALID_PAGE) {mCurrentPage = Math.max(0, Math.min(mNextPage, getPageCount() - 1));mNextPage = INVALID_PAGE;// Load the associated pages if necessary// We don't want to trigger a page end moving unless the page has// settled// and the user has stopped scrollingif (mTouchState == TOUCH_STATE_REST) {pageEndMoving();}// Notify the user when the page changesAccessibilityManager accessibilityManager = (AccessibilityManager) getContext().getSystemService(Context.ACCESSIBILITY_SERVICE);if (accessibilityManager.isEnabled()) {AccessibilityEvent ev = AccessibilityEvent.obtain(AccessibilityEvent.TYPE_VIEW_SCROLLED);sendAccessibilityEventUnchecked(ev);}return true;}return false;}@Overridepublic void computeScroll() {computeScrollHelper();}//add wufen-------//分页监听public interface OnScreenChangeListener {void onScreenChange(int currentIndex);}private OnScreenChangeListener onScreenChangeListener;public void setOnScreenChangeListener(OnScreenChangeListener onScreenChangeListener) {this.onScreenChangeListener = onScreenChangeListener;}// 动态数据监听public interface OnScreenChangeListenerDataLoad {void onScreenChange(int currentIndex);}private OnScreenChangeListenerDataLoad onScreenChangeListenerDataLoad;public void setOnScreenChangeListenerDataLoad(OnScreenChangeListenerDataLoad onScreenChangeListenerDataLoad) {this.onScreenChangeListenerDataLoad = onScreenChangeListenerDataLoad;}//-------
}