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.youkuaiyun.com/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
// shifts
private 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 factor
protected 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 pages
protected boolean mContentIsRefreshable = true;
// If true, modify alpha of neighboring pages as user scrolls left/right
protected boolean mFadeInAdjacentScreens = true;
// It true, use a different slop parameter (pagingTouchSlop = 2 * touchSlop)
// for deciding
// to switch to a new page
protected 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 changes
protected boolean mHapticFlingStarted = false;
protected boolean mHapticCaptureFling = true;
protected int mLastHapticScreen = 0;
ZInterpolator mZInterpolator = new ZInterpolator(0.5f);
// End Immersion changes
public 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);
}
@Override
protected 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 dimension
if (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_CONTENT
final 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 necessary
if (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;
}
}
@Override
protected 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;
}
}
@Override
public 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 swipe
if (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 touch
mDownMotionX = 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 page
if (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));
}
@Override
public 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 started
mDownMotionX = 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 event
final 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 page
int 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 page
int 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;
}
@Override
public 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 scroll
final 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 behavior
protected void onPageBeginMoving() {
// Begin Immersion changes
if (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 behavior
protected void onPageEndMoving() {
// Reset the Flags
mHapticCaptureFling = true;
mHapticFlingStarted = false;
// End Immersion changes
mForceDrawAllChildrenNextFrame = 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 axis
mTouchState = 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 flinging
snapToPage(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;
//wufen
onScreenChangeListener.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 settles
invalidate();
}
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 frame
mForceScreenScrolled = false;
screenScrolled(screenCenter);
mLastScreenCenter = screenCenter;
}
// Find out which screens are visible; as an optimization we only call
// draw on them
final 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 bounds
canvas.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 layer
for (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 position
alpha = 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 left
v.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 motion
translationX = 0;
} else if (i == getChildCount() - 1
&& scrollProgress > 0) {
// Overscroll to the right
v.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 touches
if (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);
}
@Override
public void scrollBy(int x, int y) {
scrollTo(mUnboundedScrollX + x, getScrollY() + y);
}
@Override
public 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 screen
float f = OVERSCROLL_ACCELERATE_FACTOR * (amount / screenSize);
if (f == 0)
return;
// Clamp this factor, f, to -1 < f < 1
if (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 moved
if (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 scrolling
if (mTouchState == TOUCH_STATE_REST) {
pageEndMoving();
}
// Notify the user when the page changes
AccessibilityManager accessibilityManager = (AccessibilityManager) getContext()
.getSystemService(Context.ACCESSIBILITY_SERVICE);
if (accessibilityManager.isEnabled()) {
AccessibilityEvent ev = AccessibilityEvent
.obtain(AccessibilityEvent.TYPE_VIEW_SCROLLED);
sendAccessibilityEventUnchecked(ev);
}
return true;
}
return false;
}
@Override
public 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;
}
//-------
}
扫一扫
1182
被折叠的 条评论
为什么被折叠?
到【灌水乐园】发言
