实例介绍
【实例简介】
【实例截图】
【核心代码】
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 | import android.content.Context;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.Rect;import android.util.AttributeSet;import android.util.Log;import android.view.MotionEvent;import android.view.VelocityTracker;import android.view.View;import android.view.ViewConfiguration;import android.view.ViewGroup;import android.widget.Scroller;/** * @author Administrator * */public class ScrollableViewGroup extends ViewGroup { private static final int INVALID_SCREEN = -1; private static final int TOUCH_STATE_REST = 0; private static final int TOUCH_STATE_SCROLLING = 1; private static final int SNAP_VELOCITY = 1000; private int mDefaultScreen; private int mCurrentScreen; private int mNextScreen = INVALID_SCREEN; private int mMaximumVelocity; private Scroller mScroller; private int mTouchState; private boolean mFirstLayout = true; private float mLastMotionX; private float mLastMotionY; private int mTouchSlop; private boolean mAllowLongPress; private VelocityTracker mVelocityTracker; private int mPaintFlag = 0; private OnCurrentViewChangedListener mOnCurrentViewChangedListener; public interface OnCurrentViewChangedListener { public void onCurrentViewChanged(View view, int currentview); }; /** * @param context */ public ScrollableViewGroup(Context context) { super(context); initViewGroup(); } /** * @param context * @param attrs */ public ScrollableViewGroup(Context context, AttributeSet attrs) { super(context, attrs); initViewGroup(); } /** * @param context * @param attrs * @param defStyle */ public ScrollableViewGroup(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); initViewGroup(); } /* * (non-Javadoc) * * @see android.view.ViewGroup#onLayout(boolean, int, int, int, int) */ @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { int childLeft = 0; final int count = getChildCount(); for (int i = 0; i < count; i ) { final View child = getChildAt(i); if (child.getVisibility() != View.GONE) { final int childWidth = child.getMeasuredWidth(); child.layout(childLeft, 0, childLeft childWidth, child .getMeasuredHeight()); childLeft = childWidth; } } } /** * Initializes various states for this viewgroup. */ private void initViewGroup() { mScroller = new Scroller(getContext()); mCurrentScreen = mDefaultScreen; final ViewConfiguration configuration = ViewConfiguration .get(getContext()); mTouchSlop = configuration.getScaledTouchSlop(); // mMaximumVelocity = configuration.getScaledMaximumFlingVelocity(); } public boolean isDefaultViewShowing() { return mCurrentScreen == mDefaultScreen; } public int getCurrentView() { return mCurrentScreen; } public void setCurrentView(int currentView) { // snapToScreen(currentView); mCurrentScreen = Math .max(0, Math.min(currentView, getChildCount() - 1)); scrollTo(mCurrentScreen * getWidth(), 0); if (mOnCurrentViewChangedListener != null) mOnCurrentViewChangedListener.onCurrentViewChanged(this, mCurrentScreen); invalidate(); } /* * (non-Javadoc) * * @see android.view.View#computeScroll() */ @Override public void computeScroll() { // Log.d("Curt", "computeScroll"); if (mScroller.computeScrollOffset()) { // FIXED 鍗峰姩鏃犳硶瑙﹀彂涓嬫鐨刢omputeScroll; final int currx = mScroller.getCurrX(), curry = mScroller .getCurrY(), scrx = getScrollX(), scry = getScrollY(); if (currx != scrx || curry != scry) scrollTo(mScroller.getCurrX(), mScroller.getCurrY()); else invalidate(); } else if (mNextScreen != INVALID_SCREEN) { mCurrentScreen = Math.max(0, Math.min(mNextScreen, getChildCount() - 1)); mNextScreen = INVALID_SCREEN; mPaintFlag = 0; clearChildrenCache(); final int scrx = getScrollX(), scry = getScrollY(), mCurrentScrollX = mCurrentScreen * getWidth(); if (scrx != mCurrentScrollX) scrollTo(mCurrentScrollX, scry); if (mOnCurrentViewChangedListener != null) mOnCurrentViewChangedListener.onCurrentViewChanged(this, mCurrentScreen); } } /* * (non-Javadoc) * * @see android.view.ViewGroup#dispatchDraw(android.graphics.Canvas) */ @Override protected void dispatchDraw(Canvas canvas) { boolean fastDraw = mTouchState != TOUCH_STATE_SCROLLING && mNextScreen == INVALID_SCREEN; // If we are not scrolling or flinging, draw only the current screen if (fastDraw) { drawChild(canvas, getChildAt(mCurrentScreen), getDrawingTime()); } else { final long drawingTime = getDrawingTime(); // If we are flinging, draw only the current screen and the target // screen if (mNextScreen >= 0 && mNextScreen < getChildCount() && (Math.abs(mCurrentScreen - mNextScreen) == 1 || mPaintFlag != 0)) { final View viewCurrent = getChildAt(mCurrentScreen), viewNext = getChildAt(mNextScreen); drawChild(canvas, viewCurrent, drawingTime); if (mPaintFlag == 0) { drawChild(canvas, viewNext, drawingTime); } else { Paint paint = new Paint(); if (mPaintFlag < 0) { canvas.drawBitmap(viewNext.getDrawingCache(), -viewNext .getWidth(), viewNext.getTop(), paint); } else { canvas.drawBitmap(viewNext.getDrawingCache(), getWidth() * getChildCount(), viewNext.getTop(), paint); } } } else { // If we are scrolling, draw all of our children final int count = getChildCount(); for (int i = 0; i < count; i ) { drawChild(canvas, getChildAt(i), drawingTime); } if (mPaintFlag != 0) { final View viewNext; Paint paint = new Paint(); if (mPaintFlag < 0) { viewNext = getChildAt(getChildCount() - 1); // Log.d("Curt", "dispatchDraw: " viewNext.getDrawingCache()); if (viewNext.getDrawingCache() == null) { viewNext.buildDrawingCache(); } canvas.drawBitmap(viewNext.getDrawingCache(), -viewNext .getWidth(), viewNext.getTop(), paint); } else { viewNext = getChildAt(0); canvas.drawBitmap(viewNext.getDrawingCache(), getWidth() * getChildCount(), viewNext.getTop(), paint); } } } } } /* * (non-Javadoc) * * @see android.view.View#onMeasure(int, int) */ @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); final int width = MeasureSpec.getSize(widthMeasureSpec); final int count = getChildCount(); for (int i = 0; i < count; i ) { getChildAt(i).measure(widthMeasureSpec, heightMeasureSpec); } if (mFirstLayout) { scrollTo(mCurrentScreen * width, 0); mFirstLayout = false; } } /* * (non-Javadoc) * * @see * android.view.ViewGroup#requestChildRectangleOnScreen(android.view.View, * android.graphics.Rect, boolean) */ @Override public boolean requestChildRectangleOnScreen(View child, Rect rectangle, boolean immediate) { int screen = indexOfChild(child); if (screen != mCurrentScreen || !mScroller.isFinished()) { snapToScreen(screen); return true; } return false; } /* * (non-Javadoc) * * @see android.view.ViewGroup#onRequestFocusInDescendants(int, * android.graphics.Rect) */ @Override protected boolean onRequestFocusInDescendants(int direction, Rect previouslyFocusedRect) { int focusableScreen; if (mNextScreen != INVALID_SCREEN) { focusableScreen = mNextScreen; } else { focusableScreen = mCurrentScreen; } // Log.d("Curt", "onRequestFocusInDescendants: " focusableScreen); boolean log = getChildAt(focusableScreen).requestFocus(direction, previouslyFocusedRect); // Log.d("Curt", "onRequestFocusInDescendants" log); return false; } /* * (non-Javadoc) * * @see android.view.ViewGroup#dispatchUnhandledMove(android.view.View, int) */ @Override public boolean dispatchUnhandledMove(View focused, int direction) { if (direction == View.FOCUS_LEFT) { if (getCurrentView() > 0) { snapToScreen(getCurrentView() - 1); return true; } } else if (direction == View.FOCUS_RIGHT) { if (getCurrentView() < getChildCount() - 1) { snapToScreen(getCurrentView() 1); return true; } } return super.dispatchUnhandledMove(focused, direction); } /* * (non-Javadoc) * * @see * android.view.ViewGroup#onInterceptTouchEvent(android.view.MotionEvent) */ @Override public boolean onInterceptTouchEvent(MotionEvent ev) { // Log.d("Curt", "onInterceptTouchEvent"); final int action = ev.getAction(); if ((action == MotionEvent.ACTION_MOVE) && (mTouchState != TOUCH_STATE_REST)) { return true; } final float x = ev.getX(); final float y = ev.getY(); switch (action) { case MotionEvent.ACTION_MOVE: final int xDiff = (int) Math.abs(x - mLastMotionX); final int yDiff = (int) Math.abs(y - mLastMotionY); final int touchSlop = mTouchSlop; boolean xMoved = xDiff > touchSlop; boolean yMoved = yDiff > touchSlop; if (xMoved || yMoved) { if (xMoved) { // Scroll if the user moved far enough along the X axis mTouchState = TOUCH_STATE_SCROLLING; enableChildrenCache(); } // Either way, cancel any pending longpress if (mAllowLongPress) { mAllowLongPress = false; // Try canceling the long press. It could also have been // scheduled // by a distant descendant, so use the mAllowLongPress flag // to block // everything final View currentScreen = getChildAt(mCurrentScreen); currentScreen.cancelLongPress(); } } break; case MotionEvent.ACTION_DOWN: // Remember location of down touch mLastMotionX = x; mLastMotionY = y; mAllowLongPress = true; /* * If being flinged and user touches the screen, initiate drag; * otherwise don't. mScroller.isFinished should be false when being * flinged. */ mTouchState = mScroller.isFinished() ? TOUCH_STATE_REST : TOUCH_STATE_SCROLLING; break; case MotionEvent.ACTION_CANCEL: case MotionEvent.ACTION_UP: mTouchState = TOUCH_STATE_REST; mAllowLongPress = false; break; } /* * The only time we want to intercept motion events is if we are in the * drag mode. */ return mTouchState != TOUCH_STATE_REST; } void enableChildrenCache() { final int count = getChildCount(); for (int i = 0; i < count; i ) { final View layout = getChildAt(i); layout.setDrawingCacheEnabled(true); if (layout instanceof ViewGroup) { ((ViewGroup) layout).setAlwaysDrawnWithCacheEnabled(true); } } } void clearChildrenCache() { final int count = getChildCount(); for (int i = 0; i < count; i ) { final View layout = getChildAt(i); if (layout instanceof ViewGroup) { ((ViewGroup) layout).setAlwaysDrawnWithCacheEnabled(false); } } } /* * (non-Javadoc) * * @see android.view.View#onTouchEvent(android.view.MotionEvent) */ @Override public boolean onTouchEvent(MotionEvent event) { if (mVelocityTracker == null) { mVelocityTracker = VelocityTracker.obtain(); } mVelocityTracker.addMovement(event); final int action = event.getAction(); final float x = event.getX(); switch (action) { 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 mLastMotionX = x; mTouchState = TOUCH_STATE_SCROLLING; break; case MotionEvent.ACTION_MOVE: // Log.d("Curt", "move : " mTouchState); if (mTouchState == TOUCH_STATE_SCROLLING) { // Scroll to follow the motion event final int deltaX = (int) (mLastMotionX - x); mLastMotionX = x; if (deltaX < 0) { /* * if (getScrollX() > 0) { scrollBy(Math.max(-getScrollX(), * deltaX), 0); } */ if (getScrollX() <= 0) { mPaintFlag = -1; } scrollBy(deltaX, 0); } else if (deltaX > 0) { int availableToScroll = getChildAt(getChildCount() - 1) .getRight() - getScrollX() - getWidth(); /* * if (availableToScroll > 0) { * scrollBy(Math.min(availableToScroll, deltaX), 0); } */ if (availableToScroll <= 0) { mPaintFlag = 1; availableToScroll = getWidth() << 1; } if (availableToScroll > 0) scrollBy(Math.min(availableToScroll, deltaX), 0); } } break; case MotionEvent.ACTION_UP: if (mTouchState == TOUCH_STATE_SCROLLING) { final VelocityTracker velocityTracker = mVelocityTracker; // velocityTracker.computeCurrentVelocity(1000, // mMaximumVelocity); int velocityX = (int) velocityTracker.getXVelocity(); if (velocityX > SNAP_VELOCITY && mCurrentScreen > 0) { // Fling hard enough to move left snapToScreen(mCurrentScreen - 1); } else if (velocityX < -SNAP_VELOCITY && mCurrentScreen < getChildCount() - 1) { // Fling hard enough to move right snapToScreen(mCurrentScreen 1); } else { snapToDestination(); } if (mVelocityTracker != null) { mVelocityTracker.recycle(); mVelocityTracker = null; } } mTouchState = TOUCH_STATE_REST; break; case MotionEvent.ACTION_CANCEL: // Log.d("Curt", "cancel"); mTouchState = TOUCH_STATE_REST; } return true; } private void snapToDestination() { final int screenWidth = getWidth(); final int scrollWidth = getScrollX() (screenWidth >> 1); final int viewCount = getChildCount(); final int whichScreen; if (scrollWidth < 0) whichScreen = -1; else if (scrollWidth > screenWidth * viewCount) whichScreen = viewCount; else whichScreen = (getScrollX() (screenWidth / 2)) / screenWidth; snapToScreen(whichScreen); } public void snapToScreen(int whichScreen) { // Log.d("Curt", "snapToScreen"); if (whichScreen != mCurrentScreen) { View child = getChildAt(mCurrentScreen); if (child instanceof ImageViewTouch) { ImageViewTouch touch = (ImageViewTouch) child; if (touch.isSmaller) { touch.zoomTo(1.0f); touch.isSmaller = false; } } } else { View child = getChildAt(mCurrentScreen); if (child instanceof ImageViewTouch) { ImageViewTouch touch = (ImageViewTouch) child; if (touch.isSmaller) { touch.zoomTo(1.0f); touch.isSmaller = false; } } } if (!mScroller.isFinished()) return; enableChildrenCache(); final int viewCount = getChildCount() - 1; final int oldWhichScreen = whichScreen; if (whichScreen < 0) { whichScreen = viewCount; mPaintFlag = -1; // next screen should be painted before current } else if (whichScreen > viewCount) { whichScreen = 0; mPaintFlag = 1; } else mPaintFlag = 0; // whichScreen = Math.max(0, Math.min(whichScreen, getChildCount() - // 1)); boolean changingScreens = whichScreen != mCurrentScreen; mNextScreen = whichScreen; View focusedChild = getFocusedChild(); Log.d("Curt", "snapToScreen: Child is: " focusedChild); if (focusedChild != null && changingScreens && focusedChild == getChildAt(mCurrentScreen)) { focusedChild.clearFocus(); } //getChildAt(mCurrentScreen).requestFocus(); //Log.d("Curt", "snapToScreen: " mCurrentScreen); final int newX = oldWhichScreen * getWidth(); final int delta = newX - getScrollX(); mScroller.startScroll(getScrollX(), 0, delta, 0, Math.abs(delta) * 2); invalidate(); /* * if (!mScroller.isFinished()) return; enableChildrenCache(); * * whichScreen = Math.max(0, Math.min(whichScreen, getChildCount() - * 1)); boolean changingScreens = whichScreen != mCurrentScreen; * * mNextScreen = whichScreen; * * View focusedChild = getFocusedChild(); if (focusedChild != null && * changingScreens && focusedChild == getChildAt(mCurrentScreen)) { * focusedChild.clearFocus(); } * * final int newX = whichScreen * getWidth(); final int delta = newX - * getScrollX(); mScroller.startScroll(getScrollX(), 0, delta, 0, * Math.abs(delta) * 2); * * invalidate(); */} public void scrollLeft() { if (mNextScreen == INVALID_SCREEN && mCurrentScreen > 0 && mScroller.isFinished()) { snapToScreen(mCurrentScreen - 1); } } public void scrollRight() { if (mNextScreen == INVALID_SCREEN && mCurrentScreen < getChildCount() - 1 && mScroller.isFinished()) { snapToScreen(mCurrentScreen 1); } } public void moveToDefaultScreen() { snapToScreen(mDefaultScreen); getChildAt(mDefaultScreen).requestFocus(); } public boolean isScrollFinish() { return mTouchState != TOUCH_STATE_SCROLLING && mNextScreen == INVALID_SCREEN; // return mScroller.isFinished(); } public OnCurrentViewChangedListener getOnCurrentViewChangedListener() { return mOnCurrentViewChangedListener; } public void setOnCurrentViewChangedListener( OnCurrentViewChangedListener mOnCurrentViewChangedListener) { this.mOnCurrentViewChangedListener = mOnCurrentViewChangedListener; }} |
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