Java tutorial
/* * SlidingLayer.java * * Copyright (C) 2013 6 Wunderkinder GmbH. * * @author Jose L Ugia - @Jl_Ugia * @author Antonio Consuegra - @aconsuegra * @author Cesar Valiente - @CesarValiente * @version 1.0 * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.ozbo.interpretation.slidinglayout; import android.content.Context; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Point; import android.graphics.drawable.Drawable; import android.os.Build; import android.support.v4.view.MotionEventCompat; import android.support.v4.view.VelocityTrackerCompat; import android.support.v4.view.ViewConfigurationCompat; import android.util.AttributeSet; import android.util.FloatMath; import android.view.Display; import android.view.MotionEvent; import android.view.VelocityTracker; import android.view.View; import android.view.ViewConfiguration; import android.view.WindowManager; import android.view.animation.Interpolator; import android.widget.FrameLayout; import android.widget.Scroller; import com.ozbo.interpretation.R; import java.lang.reflect.Method; import java.util.Random; public class SlidingLayer extends FrameLayout { /** * Default value for the position of the layer. STICK_TO_AUTO shall inspect the container and choose a stick * mode depending on the position of the layout (ie.: layout is positioned on the right = STICK_TO_RIGHT). */ public static final int STICK_TO_AUTO = 0; /** * Special value for the position of the layer. STICK_TO_RIGHT means that the view shall be attached to the * right side of the screen, and come from there into the viewable area. */ public static final int STICK_TO_RIGHT = -1; /** * Special value for the position of the layer. STICK_TO_LEFT means that the view shall be attached to the left * side of the screen, and come from there into the viewable area. */ public static final int STICK_TO_LEFT = -2; /** * Special value for the position of the layer. STICK_TO_MIDDLE means that the view will stay attached trying to * be in the middle of the screen and allowing dismissing both to right and left side. */ public static final int STICK_TO_MIDDLE = -3; /** * Special value for the position of the layer. STICK_TO_TOP means that the view will stay attached to the top * part of the screen, and come from there into the viewable area. */ public static final int STICK_TO_TOP = -4; /** * Special value for the position of the layer. STICK_TO_BOTTOM means that the view will stay attached to the * bottom part of the screen, and come from there into the viewable area. */ public static final int STICK_TO_BOTTOM = -5; private static final int MAX_SCROLLING_DURATION = 600; // in ms private static final int MIN_DISTANCE_FOR_FLING = 25; // in dip private static final Interpolator sMenuInterpolator = new Interpolator() { @Override public float getInterpolation(float t) { t -= 1.0f; return (float) Math.pow(t, 5) + 1.0f; } }; /** * Sentinel value for no current active pointer. Used by {@link #mActivePointerId}. */ private static final int INVALID_POINTER = -1; protected int mActivePointerId = INVALID_POINTER; protected VelocityTracker mVelocityTracker; protected int mMaximumVelocity; private Random mRandom; private Scroller mScroller; private int mShadowWidth; private Drawable mShadowDrawable; private boolean mForceLayout; /** * The with of the panel when closed */ private int mOffsetWidth; private boolean mDrawingCacheEnabled; private int mScreenSide = STICK_TO_AUTO; /** * If the user taps the layer then we will close it if enabled. */ private boolean closeOnTapEnabled = true; /** * If the user taps the offset then we will open it if enabled. */ private boolean openOnTapEnabled = true; private boolean mEnabled = true; private boolean mSlidingFromShadowEnabled = true; private boolean mIsDragging; private boolean mIsUnableToDrag; private int mTouchSlop; private float mLastX = -1; private float mLastY = -1; private float mInitialX = -1; private float mInitialY = -1; private boolean mIsOpen; private boolean mScrolling; private OnInteractListener mOnInteractListener; private int mMinimumVelocity; private int mFlingDistance; private boolean mLastTouchAllowed = false; public SlidingLayer(Context context) { this(context, null); } public SlidingLayer(Context context, AttributeSet attrs) { this(context, attrs, 0); } /** * Constructor for the sliding layer.<br> * By default this panel will * <ol> * <li>{@link #setStickTo(int)} with param {@link #STICK_TO_AUTO}</li> * <li>Use no shadow drawable. (i.e. with width of 0)</li> * <li>Close when the panel is tapped</li> * <li>Open when the offset is tapped, but will have an offset of 0</li> * </ol> * @param context a reference to an existing context * @param attrs attribute set constructed from attributes set in android .xml file * @param defStyle style res id */ public SlidingLayer(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); // Style final TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.SlidingLayer); // Set the side of the screen setStickTo(ta.getInt(R.styleable.SlidingLayer_stickTo, STICK_TO_AUTO)); // Sets the shadow drawable int shadowRes = ta.getResourceId(R.styleable.SlidingLayer_shadowDrawable, -1); if (shadowRes != -1) { setShadowDrawable(shadowRes); } // Sets the shadow width setShadowWidth((int) ta.getDimension(R.styleable.SlidingLayer_shadowWidth, 0)); // Sets the ability to close the layer by tapping in any empty space closeOnTapEnabled = ta.getBoolean(R.styleable.SlidingLayer_closeOnTapEnabled, true); // Sets the ability to open the layout by tapping on any of the exposed closed layer openOnTapEnabled = ta.getBoolean(R.styleable.SlidingLayer_openOnTapEnabled, true); // How much of the view sticks out when closed setOffsetWidth(ta.getDimensionPixelOffset(R.styleable.SlidingLayer_offsetWidth, 0)); ta.recycle(); init(); } private void init() { setWillNotDraw(false); setDescendantFocusability(FOCUS_AFTER_DESCENDANTS); setFocusable(true); final Context context = getContext(); mScroller = new Scroller(context, sMenuInterpolator); final ViewConfiguration configuration = ViewConfiguration.get(context); mTouchSlop = ViewConfigurationCompat.getScaledPagingTouchSlop(configuration); mMinimumVelocity = configuration.getScaledMinimumFlingVelocity(); mMaximumVelocity = configuration.getScaledMaximumFlingVelocity(); final float density = context.getResources().getDisplayMetrics().density; mFlingDistance = (int) (MIN_DISTANCE_FOR_FLING * density); mRandom = new Random(); } /** * Returns whether the panel is open or not. * @return returns true if the panel is open, false otherwise. Please note that if * the panel was opened with smooth animation this method is not guaranteed to return * true. This method will only return true after the panel has completely opened. */ public boolean isOpened() { return mIsOpen; } public void openLayer(boolean smoothAnim) { openLayer(smoothAnim, false); } private void openLayer(boolean smoothAnim, boolean forceOpen) { switchLayer(true, smoothAnim, forceOpen, 0, 0); } public void closeLayer(boolean smoothAnim) { closeLayer(smoothAnim, false); } private void closeLayer(boolean smoothAnim, boolean forceClose) { switchLayer(false, smoothAnim, forceClose, 0, 0); } private void switchLayer(boolean open, boolean smoothAnim, boolean forceSwitch) { switchLayer(open, smoothAnim, forceSwitch, 0, 0); } private void switchLayer(final boolean open, final boolean smoothAnim, final boolean forceSwitch, final int velocityX, final int velocityY) { if (!forceSwitch && open == mIsOpen) { setDrawingCacheEnabled(false); return; } if (open) { if (mOnInteractListener != null) { mOnInteractListener.onOpen(); } } else { if (mOnInteractListener != null) { mOnInteractListener.onClose(); } } mIsOpen = open; // Get translation values float tx = mLastX - getWidth() / 2; float ty = mLastY - getHeight() / 2; // Get boolean for velocity check boolean noVelocityInStickToMidle = mScreenSide == STICK_TO_MIDDLE && Math.abs(velocityX) < mMinimumVelocity && Math.abs(velocityY) < mMinimumVelocity; // Follow velocity or translation depending on the case int dx = noVelocityInStickToMidle ? (int) tx : velocityX; int dy = noVelocityInStickToMidle ? (int) ty : velocityY; final int pos[] = getDestScrollPos(dx, dy); if (smoothAnim) { smoothScrollTo(pos[0], pos[1], Math.max(velocityX, velocityY)); } else { completeScroll(); scrollTo(pos[0], pos[1]); } } /** * Sets the listener to be invoked after a switch change {@link com.ozbo.interpretation.slidinglayout.SlidingLayer.OnInteractListener}. * * @param listener * Listener to set */ public void setOnInteractListener(OnInteractListener listener) { mOnInteractListener = listener; } /** * Sets the shadow width by the value of a resource. * * @param resId * The dimension resource id to be set as the shadow width. */ public void setShadowWidthRes(int resId) { setShadowWidth((int) getResources().getDimension(resId)); } /** * Return the current with of the shadow. * * @return The size of the shadow in pixels */ public int getShadowWidth() { return mShadowWidth; } /** * Sets the shadow of the width which will be included within the view by using padding since it's on the left * of the view in this case * * @param shadowWidth * Desired width of the shadow * @see #getShadowWidth() * @see #setShadowDrawable(android.graphics.drawable.Drawable) * @see #setShadowDrawable(int) */ public void setShadowWidth(final int shadowWidth) { mShadowWidth = shadowWidth; invalidate(getLeft(), getTop(), getRight(), getBottom()); } /** * Sets a drawable that will be used to create the shadow for the layer. * * @param d * Drawable append as a shadow */ public void setShadowDrawable(final Drawable d) { mShadowDrawable = d; refreshDrawableState(); setWillNotDraw(false); invalidate(getLeft(), getTop(), getRight(), getBottom()); } /** * Sets a drawable resource that will be used to create the shadow for the layer. * * @param resId * Resource ID of a drawable */ public void setShadowDrawable(int resId) { setShadowDrawable(getContext().getResources().getDrawable(resId)); } /** * Sets the offset width of the panel. How much sticks out when off screen. * * @param offsetWidth * Width of the offset in pixels * @see #getOffsetWidth() */ public void setOffsetWidth(int offsetWidth) { mOffsetWidth = offsetWidth; invalidate(getLeft(), getTop(), getRight(), getBottom()); } /** * * @return returns the number of pixels that are visible when the panel is closed */ public int getOffsetWidth() { return mOffsetWidth; } @Override protected boolean verifyDrawable(Drawable who) { return super.verifyDrawable(who) || who == mShadowDrawable; } @Override protected void drawableStateChanged() { super.drawableStateChanged(); final Drawable d = mShadowDrawable; if (d != null && d.isStateful()) { d.setState(getDrawableState()); } } public boolean isSlidingEnabled() { return mEnabled; } public void setSlidingEnabled(boolean _enabled) { mEnabled = _enabled; } public boolean isSlidingFromShadowEnabled() { return mSlidingFromShadowEnabled; } public void setSlidingFromShadowEnabled(boolean _slidingShadow) { mSlidingFromShadowEnabled = _slidingShadow; } @Override public boolean onInterceptTouchEvent(MotionEvent ev) { if (!mEnabled) { return false; } final int action = ev.getAction() & MotionEventCompat.ACTION_MASK; if (action == MotionEvent.ACTION_CANCEL || action == MotionEvent.ACTION_UP) { mIsDragging = false; mIsUnableToDrag = false; mActivePointerId = INVALID_POINTER; if (mVelocityTracker != null) { mVelocityTracker.recycle(); mVelocityTracker = null; } return false; } if (action != MotionEvent.ACTION_DOWN) { if (mIsDragging) { return true; } else if (mIsUnableToDrag) { return false; } } switch (action) { case MotionEvent.ACTION_MOVE: final int activePointerId = mActivePointerId; if (activePointerId == INVALID_POINTER) { break; } final int pointerIndex = MotionEventCompat.findPointerIndex(ev, activePointerId); if (pointerIndex == -1) { mActivePointerId = INVALID_POINTER; break; } final float x = MotionEventCompat.getX(ev, pointerIndex); final float dx = x - mLastX; final float xDiff = Math.abs(dx); final float y = MotionEventCompat.getY(ev, pointerIndex); final float dy = y - mLastY; final float yDiff = Math.abs(y - mLastY); if (xDiff > mTouchSlop && xDiff > yDiff && allowDragingX(dx, mInitialX)) { mIsDragging = true; mLastX = x; setDrawingCacheEnabled(true); } else if (yDiff > mTouchSlop && yDiff > xDiff && allowDragingY(dy, mInitialY)) { mIsDragging = true; mLastY = y; setDrawingCacheEnabled(true); } break; case MotionEvent.ACTION_DOWN: mActivePointerId = ev.getAction() & (Build.VERSION.SDK_INT >= 8 ? MotionEvent.ACTION_POINTER_INDEX_MASK : MotionEventCompat.ACTION_POINTER_INDEX_MASK); mLastX = mInitialX = MotionEventCompat.getX(ev, mActivePointerId); mLastY = mInitialY = MotionEventCompat.getY(ev, mActivePointerId); if (allowSlidingFromHereX(ev, mInitialX)) { mIsDragging = false; mIsUnableToDrag = false; // If nobody else got the focus we use it to close the layer return super.onInterceptTouchEvent(ev); } else if (allowSlidingFromHereY(ev, mInitialY)) { mIsDragging = false; mIsUnableToDrag = false; // If nobody else got the focus we use it to close the layer return super.onInterceptTouchEvent(ev); } else { mIsUnableToDrag = true; } break; case MotionEventCompat.ACTION_POINTER_UP: onSecondaryPointerUp(ev); break; } if (!mIsDragging) { if (mVelocityTracker == null) { mVelocityTracker = VelocityTracker.obtain(); } mVelocityTracker.addMovement(ev); } return mIsDragging; } @Override public boolean onTouchEvent(MotionEvent ev) { if (!mEnabled || !mIsDragging && !mLastTouchAllowed && !allowSlidingFromHereX(ev, mInitialX) && !allowSlidingFromHereY(ev, mInitialY)) { return false; } final int action = ev.getAction(); if (action == MotionEvent.ACTION_UP || action == MotionEvent.ACTION_CANCEL || action == MotionEvent.ACTION_OUTSIDE) { mLastTouchAllowed = false; } else { mLastTouchAllowed = true; } if (mVelocityTracker == null) { mVelocityTracker = VelocityTracker.obtain(); } mVelocityTracker.addMovement(ev); switch (action & MotionEventCompat.ACTION_MASK) { case MotionEvent.ACTION_DOWN: completeScroll(); // Remember where the motion event started mLastX = mInitialX = ev.getX(); mLastY = mInitialY = ev.getY(); mActivePointerId = MotionEventCompat.getPointerId(ev, 0); break; case MotionEvent.ACTION_MOVE: if (!mIsDragging) { final int pointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId); if (pointerIndex == -1) { mActivePointerId = INVALID_POINTER; break; } final float x = MotionEventCompat.getX(ev, pointerIndex); final float xDiff = Math.abs(x - mLastX); final float y = MotionEventCompat.getY(ev, pointerIndex); final float yDiff = Math.abs(y - mLastY); if (xDiff > mTouchSlop && xDiff > yDiff) { mIsDragging = true; mLastX = x; setDrawingCacheEnabled(true); } else if (yDiff > mTouchSlop && yDiff > xDiff) { mIsDragging = true; mLastY = y; setDrawingCacheEnabled(true); } } if (mIsDragging) { // Scroll to follow the motion event final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId); if (activePointerIndex == -1) { mActivePointerId = INVALID_POINTER; break; } final float x = MotionEventCompat.getX(ev, activePointerIndex); final float y = MotionEventCompat.getY(ev, activePointerIndex); final float deltaX = mLastX - x; final float deltaY = mLastY - y; mLastX = x; mLastY = y; final float oldScrollX = getScrollX(); final float oldScrollY = getScrollY(); float scrollX = oldScrollX + deltaX; float scrollY = oldScrollY + deltaY; // Log.d("Layer", String.format("Layer scrollX[%f],scrollY[%f]", scrollX, scrollY)); final float leftBound, rightBound; final float bottomBound, topBound; switch (mScreenSide) { case STICK_TO_LEFT: topBound = bottomBound = rightBound = 0; leftBound = getWidth(); // How far left we can scroll break; case STICK_TO_MIDDLE: topBound = getHeight(); bottomBound = -getHeight(); leftBound = getWidth(); rightBound = -getWidth(); break; case STICK_TO_RIGHT: rightBound = -getWidth(); topBound = bottomBound = leftBound = 0; break; case STICK_TO_TOP: topBound = getHeight(); bottomBound = rightBound = leftBound = 0; break; case STICK_TO_BOTTOM: topBound = rightBound = leftBound = 0; bottomBound = -getHeight(); break; default: topBound = bottomBound = rightBound = leftBound = 0; break; } if (scrollX > leftBound) { scrollX = leftBound; } else if (scrollX < rightBound) { scrollX = rightBound; } if (scrollY > topBound) { scrollY = topBound; } else if (scrollY < bottomBound) { scrollY = bottomBound; } // Keep the precision mLastX += scrollX - (int) scrollX; mLastY += scrollY - (int) scrollY; scrollTo((int) scrollX, (int) scrollY); } break; case MotionEvent.ACTION_UP: if (mIsDragging) { final VelocityTracker velocityTracker = mVelocityTracker; velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity); final int initialVelocityX = (int) VelocityTrackerCompat.getXVelocity(velocityTracker, mActivePointerId); final int initialVelocityY = (int) VelocityTrackerCompat.getYVelocity(velocityTracker, mActivePointerId); final int scrollX = getScrollX(); final int scrollY = getScrollY(); final int activePointerIndex = MotionEventCompat.findPointerIndex(ev, mActivePointerId); final float x = MotionEventCompat.getX(ev, activePointerIndex); final float y = MotionEventCompat.getY(ev, activePointerIndex); final int totalDeltaX = (int) (x - mInitialX); final int totalDeltaY = (int) (y - mInitialY); boolean nextStateOpened = determineNextStateOpened(mIsOpen, scrollX, scrollY, initialVelocityX, initialVelocityY, totalDeltaX, totalDeltaY); switchLayer(nextStateOpened, true, true, initialVelocityX, initialVelocityY); mActivePointerId = INVALID_POINTER; endDrag(); } else if (mIsOpen && closeOnTapEnabled) { closeLayer(true); } else if (!mIsOpen && openOnTapEnabled) { openLayer(true); } break; case MotionEvent.ACTION_CANCEL: if (mIsDragging) { switchLayer(mIsOpen, true, true); mActivePointerId = INVALID_POINTER; endDrag(); } break; case MotionEventCompat.ACTION_POINTER_DOWN: { final int index = MotionEventCompat.getActionIndex(ev); mLastX = MotionEventCompat.getX(ev, index); mLastY = MotionEventCompat.getY(ev, index); mActivePointerId = MotionEventCompat.getPointerId(ev, index); break; } case MotionEventCompat.ACTION_POINTER_UP: onSecondaryPointerUp(ev); mLastX = MotionEventCompat.getX(ev, MotionEventCompat.findPointerIndex(ev, mActivePointerId)); mLastY = MotionEventCompat.getY(ev, MotionEventCompat.findPointerIndex(ev, mActivePointerId)); break; } if (mActivePointerId == INVALID_POINTER) { mLastTouchAllowed = false; } return true; } private boolean allowSlidingFromHereX(final MotionEvent ev, final float initialX) { switch (mScreenSide) { case STICK_TO_LEFT: case STICK_TO_RIGHT: case STICK_TO_MIDDLE: if (mIsOpen) { return true; } if (!mIsOpen && mOffsetWidth > 0) { switch (mScreenSide) { case STICK_TO_LEFT: return initialX <= mOffsetWidth; case STICK_TO_RIGHT: return initialX >= getWidth() - mOffsetWidth; } } default: return false; } } private boolean allowSlidingFromHereY(final MotionEvent ev, final float initialY) { switch (mScreenSide) { case STICK_TO_TOP: case STICK_TO_BOTTOM: case STICK_TO_MIDDLE: if (mIsOpen) { return true; } if (!mIsOpen && mOffsetWidth > 0) { switch (mScreenSide) { case STICK_TO_TOP: return initialY <= mOffsetWidth; case STICK_TO_BOTTOM: return initialY >= getHeight() - mOffsetWidth; } } default: return false; } } /** * Checks if the touch event is valid for dragging the view. * * @param dx * changed in delta from the initialX * @param initialX * where the touch event started. * @return true if you can drag this view, false otherwise */ private boolean allowDragingX(final float dx, final float initialX) { if (mIsOpen && getLeft() <= initialX || getRight() >= initialX) { switch (mScreenSide) { case STICK_TO_RIGHT: return dx > 0; case STICK_TO_LEFT: return dx < 0; case STICK_TO_MIDDLE: return dx != 0; } } if (!mIsOpen && mOffsetWidth > 0 && dx > 0) { switch (mScreenSide) { case STICK_TO_LEFT: return initialX <= mOffsetWidth && dx > 0; case STICK_TO_RIGHT: return initialX >= getWidth() - mOffsetWidth && dx < 0; case STICK_TO_MIDDLE: return dx != 0; } } return false; } private boolean allowDragingY(final float dy, final float initialY) { if (mIsOpen && getTop() <= initialY || getBottom() >= initialY) { switch (mScreenSide) { case STICK_TO_BOTTOM: return mIsOpen && dy > 0; case STICK_TO_TOP: return mIsOpen && dy < 0; case STICK_TO_MIDDLE: return mIsOpen && dy != 0; } } if (!mIsOpen && mOffsetWidth > 0 && dy > 0) { switch (mScreenSide) { case STICK_TO_TOP: return initialY <= mOffsetWidth && dy > 0; case STICK_TO_BOTTOM: return initialY >= getHeight() - mOffsetWidth && dy < 0; case STICK_TO_MIDDLE: return dy != 0; } } return false; } /** * Based on the current state, position and velocity of the layer we calculate what the next state should be. * * @param currentState * @param swipeOffsetX * @param swipeOffsetY * @param velocityX * @param velocityY * @param deltaX * @param deltaY * @return true means we should open it, false close it. */ private boolean determineNextStateOpened(final boolean currentState, final float swipeOffsetX, final float swipeOffsetY, final int velocityX, final int velocityY, final int deltaX, final int deltaY) { final boolean targetState; final boolean calcX; final boolean calcY; // Work out which velocity we should listen to. switch (mScreenSide) { case STICK_TO_TOP: case STICK_TO_BOTTOM: calcY = true; calcX = false; break; case STICK_TO_RIGHT: case STICK_TO_LEFT: calcX = true; calcY = false; break; case STICK_TO_MIDDLE: calcX = calcY = true; break; default: calcX = calcY = false; break; } if (calcX && Math.abs(deltaX) > mFlingDistance && Math.abs(velocityX) > mMinimumVelocity) { targetState = mScreenSide == STICK_TO_RIGHT && velocityX <= 0 || mScreenSide == STICK_TO_LEFT && velocityX > 0; } else if (calcY && Math.abs(deltaY) > mFlingDistance && Math.abs(velocityY) > mMinimumVelocity) { targetState = mScreenSide == STICK_TO_BOTTOM && velocityY <= 0 || mScreenSide == STICK_TO_TOP && velocityY > 0; } else { final int w = getWidth(); final int h = getHeight(); switch (mScreenSide) { case STICK_TO_RIGHT: targetState = swipeOffsetX > -w / 2; break; case STICK_TO_BOTTOM: targetState = swipeOffsetY > -h / 2; break; case STICK_TO_LEFT: targetState = swipeOffsetX < w / 2; break; case STICK_TO_TOP: targetState = swipeOffsetY < h / 2; break; case STICK_TO_MIDDLE: targetState = Math.abs(swipeOffsetX) < w / 2 && Math.abs(swipeOffsetY) < h / 2; break; default: targetState = true; } } return targetState; } /** * Like {@link android.view.View#scrollBy}, but scroll smoothly instead of immediately. * * @param x * the number of pixels to scroll by on the X axis * @param y * the number of pixels to scroll by on the Y axis */ void smoothScrollTo(int x, int y) { smoothScrollTo(x, y, 0); } /** * Like {@link android.view.View#scrollBy}, but scroll smoothly instead of immediately. * * @param x * the number of pixels to scroll by on the X axis * @param y * the number of pixels to scroll by on the Y axis * @param velocity * the velocity associated with a fling, if applicable. (0 otherwise) */ void smoothScrollTo(int x, int y, int velocity) { if (getChildCount() == 0) { setDrawingCacheEnabled(false); return; } int sx = getScrollX(); int sy = getScrollY(); int dx = x - sx; int dy = y - sy; if (dx == 0 && dy == 0) { completeScroll(); if (mIsOpen) { if (mOnInteractListener != null) { mOnInteractListener.onOpened(); } } else { if (mOnInteractListener != null) { mOnInteractListener.onClosed(); } } return; } setDrawingCacheEnabled(true); mScrolling = true; final int width = getWidth(); final int halfWidth = width / 2; final float distanceRatio = Math.min(1f, 1.0f * Math.abs(dx) / width); final float distance = halfWidth + halfWidth * distanceInfluenceForSnapDuration(distanceRatio); int duration = 0; velocity = Math.abs(velocity); if (velocity > 0) { duration = 4 * Math.round(1000 * Math.abs(distance / velocity)); } else { duration = MAX_SCROLLING_DURATION; } duration = Math.min(duration, MAX_SCROLLING_DURATION); mScroller.startScroll(sx, sy, dx, dy, duration); invalidate(); } // We want the duration of the page snap animation to be influenced by the distance that // the screen has to travel, however, we don't want this duration to be effected in a // purely linear fashion. Instead, we use this method to moderate the effect that the distance // of travel has on the overall snap duration. float distanceInfluenceForSnapDuration(float f) { f -= 0.5f; // center the values about 0. f *= 0.3f * Math.PI / 2.0f; return FloatMath.sin(f); } private void endDrag() { mIsDragging = false; mIsUnableToDrag = false; mLastTouchAllowed = false; if (mVelocityTracker != null) { mVelocityTracker.recycle(); mVelocityTracker = null; } } @Override public void setDrawingCacheEnabled(boolean enabled) { if (mDrawingCacheEnabled != enabled) { super.setDrawingCacheEnabled(enabled); mDrawingCacheEnabled = enabled; final int l = getChildCount(); for (int i = 0; i < l; i++) { final View child = getChildAt(i); if (child.getVisibility() != GONE) { child.setDrawingCacheEnabled(enabled); } } } } private void onSecondaryPointerUp(MotionEvent ev) { final int pointerIndex = MotionEventCompat.getActionIndex(ev); final int pointerId = MotionEventCompat.getPointerId(ev, pointerIndex); if (pointerId == mActivePointerId) { // This was our active pointer going up. Choose a new // active pointer and adjust accordingly. final int newPointerIndex = pointerIndex == 0 ? 1 : 0; mLastX = MotionEventCompat.getX(ev, newPointerIndex); mActivePointerId = MotionEventCompat.getPointerId(ev, newPointerIndex); if (mVelocityTracker != null) { mVelocityTracker.clear(); } } } private void completeScroll() { boolean needPopulate = mScrolling; if (needPopulate) { // Done with scroll, no longer want to cache view drawing. setDrawingCacheEnabled(false); mScroller.abortAnimation(); int oldX = getScrollX(); int oldY = getScrollY(); int x = mScroller.getCurrX(); int y = mScroller.getCurrY(); if (oldX != x || oldY != y) { scrollTo(x, y); } if (mIsOpen) { if (mOnInteractListener != null) { mOnInteractListener.onOpened(); } } else { if (mOnInteractListener != null) { mOnInteractListener.onClosed(); } } } mScrolling = false; } /** * Sets the default location where the SlidingLayer will appear * @param screenSide The location where the Sliding layer will appear. Possible values are * {@link #STICK_TO_AUTO}, {@link #STICK_TO_BOTTOM}, {@link #STICK_TO_LEFT}, {@link #STICK_TO_MIDDLE} * {@link #STICK_TO_RIGHT}, {@link #STICK_TO_TOP} */ public void setStickTo(int screenSide) { if (screenSide != STICK_TO_AUTO) { mForceLayout = true; } mScreenSide = screenSide; closeLayer(false, true); } /** * If parameter is set to <code>true</code>, whenever the <code>SlidingLayer</code> is tapped and * the SlidingLayer is opened, it will attempt to close. * If parameter is set to <code>false</code>, then tapping the <code>SlidingLayer</code> will * do nothing * * @param _closeOnTapEnabled */ public void setCloseOnTapEnabled(boolean _closeOnTapEnabled) { closeOnTapEnabled = _closeOnTapEnabled; } /** * Given that there is a visible offset and it is tapped, if the parameter is set * to true it will attempt to open the <code>SlidingLayer</code>. If parameter is false, * tapping a visible offset will yield no result. * @param _openOnTapEnabled */ public void setOpenOnTapEnabled(boolean _openOnTapEnabled) { openOnTapEnabled = _openOnTapEnabled; } @SuppressWarnings("deprecation") private int getScreenSideAuto(int newLeft, int newRight) { int newScreenSide; if (mScreenSide == STICK_TO_AUTO) { int screenWidth; Display display = ((WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE)) .getDefaultDisplay(); try { Class<?> cls = Display.class; Class<?>[] parameterTypes = { Point.class }; Point parameter = new Point(); Method method = cls.getMethod("getSize", parameterTypes); method.invoke(display, parameter); screenWidth = parameter.x; } catch (Exception e) { screenWidth = display.getWidth(); } boolean boundToLeftBorder = newLeft == 0; boolean boundToRightBorder = newRight == screenWidth; if (boundToLeftBorder == boundToRightBorder && getLayoutParams().width == android.view.ViewGroup.LayoutParams.MATCH_PARENT) { newScreenSide = STICK_TO_MIDDLE; } else if (boundToLeftBorder) { newScreenSide = STICK_TO_LEFT; } else { newScreenSide = STICK_TO_RIGHT; } } else { newScreenSide = mScreenSide; } return newScreenSide; } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { int width = getDefaultSize(0, widthMeasureSpec); int height = getDefaultSize(0, heightMeasureSpec); setMeasuredDimension(width, height); super.onMeasure(getChildMeasureSpec(widthMeasureSpec, 0, width), getChildMeasureSpec(heightMeasureSpec, 0, height)); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); // Make sure scroll position is set correctly. if (w != oldw) { completeScroll(); int[] pos = getDestScrollPos(); scrollTo(pos[0], pos[1]); } } @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom) { int screenSide = mScreenSide; if (mScreenSide == STICK_TO_AUTO) { screenSide = getScreenSideAuto(left, right); } if (screenSide != mScreenSide || mForceLayout) { mForceLayout = false; mScreenSide = screenSide; closeLayer(false, true); if (mScreenSide == STICK_TO_RIGHT) { setPadding(getPaddingLeft() + mShadowWidth, getPaddingTop(), getPaddingRight(), getPaddingBottom()); } else if (mScreenSide == STICK_TO_BOTTOM) { setPadding(getPaddingLeft(), getPaddingTop() + mShadowWidth, getPaddingRight(), getPaddingBottom()); } else if (mScreenSide == STICK_TO_LEFT) { setPadding(getPaddingLeft(), getPaddingTop(), getPaddingRight() + mShadowWidth, getPaddingBottom()); } else if (mScreenSide == STICK_TO_TOP) { setPadding(getPaddingLeft(), getPaddingTop(), getPaddingRight(), getPaddingBottom() + mShadowWidth); } else if (mScreenSide == STICK_TO_MIDDLE) { setPadding(getPaddingLeft() + mShadowWidth, getPaddingTop(), getPaddingRight() + mShadowWidth, getPaddingBottom()); } } super.onLayout(changed, left, top, right, bottom); } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); } private int[] getDestScrollPos() { return getDestScrollPos(0, 0); } /** * Get the x destination based on the velocity * * @param xValue * @param yValue * @return * @since 1.0 * */ private int[] getDestScrollPos(int xValue, int yValue) { int[] pos = new int[2]; if (mIsOpen) { return pos; } else { switch (mScreenSide) { case STICK_TO_RIGHT: pos[0] = -getWidth() + mOffsetWidth; break; case STICK_TO_LEFT: pos[0] = getWidth() - mOffsetWidth; break; case STICK_TO_TOP: pos[1] = getHeight() - mOffsetWidth; break; case STICK_TO_BOTTOM: pos[1] = -getHeight() + mOffsetWidth; break; case STICK_TO_MIDDLE: // Calculate slope m to get direction of swiping and apply the same vector until the end of the // animation float m = 1; // If no veocity nor translation (difficult to get) the target is random if (xValue == 0 && yValue == 0) { m = mRandom != null ? (float) Math.tan(mRandom.nextFloat() * Math.PI - Math.PI / 2) : 1; } else if (xValue == 0) { // Avoid division by 0 (Get the max value of the tan which is equivalent) m = (float) Math.tan(Math.PI / 2); } else { // Get slope m = yValue / (float) xValue; } if (Math.abs(m) >= 1) { pos[0] = Math.round(getOperationSignForDiffMeasure(xValue) * getHeight() / Math.abs(m) - (mLastX - getWidth() / 2)); pos[1] = Math.round(getOperationSignForDiffMeasure(yValue) * getHeight()); } else { pos[0] = Math.round(getOperationSignForDiffMeasure(xValue) * getWidth()); pos[1] = Math.round(getOperationSignForDiffMeasure(yValue) * getWidth() * Math.abs(m) - (mLastY - getHeight() / 2)); } break; } return pos; } } private int getOperationSignForDiffMeasure(float d) { if (mRandom == null) { return 1; } else { return Math.abs(d) < mMinimumVelocity ? mRandom.nextBoolean() ? 1 : -1 : d > 0 ? -1 : 1; } } public int getContentLeft() { return getLeft() + getPaddingLeft(); } @Override protected void dispatchDraw(Canvas canvas) { super.dispatchDraw(canvas); // Draw the margin drawable if needed. if (mShadowWidth > 0 && mShadowDrawable != null) { if (mScreenSide == STICK_TO_RIGHT) { mShadowDrawable.setBounds(0, 0, mShadowWidth, getHeight()); } if (mScreenSide == STICK_TO_TOP) { mShadowDrawable.setBounds(0, getHeight() - mShadowWidth, getWidth(), getHeight()); } if (mScreenSide == STICK_TO_LEFT) { mShadowDrawable.setBounds(getWidth() - mShadowWidth, 0, getWidth(), getHeight()); } if (mScreenSide == STICK_TO_BOTTOM) { mShadowDrawable.setBounds(0, 0, getWidth(), mShadowWidth); } mShadowDrawable.draw(canvas); } } @Override public void computeScroll() { if (!mScroller.isFinished()) { if (mScroller.computeScrollOffset()) { final int oldX = getScrollX(); final int oldY = getScrollY(); final int x = mScroller.getCurrX(); final int y = mScroller.getCurrY(); if (oldX != x || oldY != y) { scrollTo(x, y); } // We invalidate a slightly larger area now, this was only optimised for right menu previously // Keep on drawing until the animation has finished. Just re-draw the necessary part invalidate(getLeft() + oldX, getTop() + oldY, getRight() - oldX, getBottom() - oldY); return; } } // Done with scroll, clean up state. completeScroll(); } /** * Handler interface for obtaining updates on the <code>SlidingLayer</code>'s state. * <code>OnInteractListener</code> allows for external classes to be notified when the <code>SlidingLayer</code> * receives input to be opened or closed. */ public interface OnInteractListener { /** * This method is called when an attempt is made to open the current <code>SlidingLayer</code>. Note * that because of animation, the <code>SlidingLayer</code> may not be visible yet. */ public void onOpen(); /** * This method is called when an attempt is made to close the current <code>SlidingLayer</code>. Note * that because of animation, the <code>SlidingLayer</code> may still be visible. */ public void onClose(); /** * this method is executed after <code>onOpen()</code>, when the animation has finished. */ public void onOpened(); /** * this method is executed after <code>onClose()</code>, when the animation has finished and the <code>SlidingLayer</code> is * therefore no longer visible. */ public void onClosed(); } }