RecyclerView进阶使用-实现仿支付宝菜单编辑页面拖拽功能(改版)

/* * Copyright (C) 2015 Haruki Hasegawa * * 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.h6ah4i.android.widget.advrecyclerview.draggable; import android.graphics.Rect; import android.graphics.drawable.NinePatchDrawable; import android.os.Build; import android.os.Handler; import android.os.Message; import android.support.annotation.FloatRange; import android.support.annotation.IntDef; import android.support.annotation.NonNull; import android.support.annotation.Nullable; import android.support.v4.view.MotionEventCompat; import android.support.v4.view.ViewCompat; import android.support.v4.widget.NestedScrollView; import android.support.v7.widget.RecyclerView; import android.util.Log; import android.view.MotionEvent; import android.view.View; import android.view.ViewConfiguration; import android.view.ViewGroup; import android.view.ViewParent; import android.view.animation.DecelerateInterpolator; import android.view.animation.Interpolator; import com.h6ah4i.android.widget.advrecyclerview.adapter.AdapterPath; import com.h6ah4i.android.widget.advrecyclerview.adapter.ItemIdComposer; import com.h6ah4i.android.widget.advrecyclerview.utils.CustomRecyclerViewUtils; import com.h6ah4i.android.widget.advrecyclerview.utils.WrapperAdapterUtils; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.ref.WeakReference; /** * Provides item drag &amp; drop operation for {@link android.support.v7.widget.RecyclerView} */ @SuppressWarnings("PointlessBitwiseExpression") public class RecyclerViewDragDropManager implements DraggableItemConstants { private static final String TAG = "ARVDragDropManager"; /** * Default interpolator used for "swap target transition" */ public static final Interpolator DEFAULT_SWAP_TARGET_TRANSITION_INTERPOLATOR = new BasicSwapTargetTranslationInterpolator(); /** * Default interpolator used for "item settle back into place" animation */ public static final Interpolator DEFAULT_ITEM_SETTLE_BACK_INTO_PLACE_ANIMATION_INTERPOLATOR = new DecelerateInterpolator(); @Retention(RetentionPolicy.SOURCE) @IntDef({ITEM_MOVE_MODE_DEFAULT, ITEM_MOVE_MODE_SWAP}) public @interface ItemMoveMode { } /** * Default item move mode */ public static final int ITEM_MOVE_MODE_DEFAULT = 0; /** * Swap two items between dragging item and the item under a finger (or mouse pointer) */ public static final int ITEM_MOVE_MODE_SWAP = 1; // --- /** * Used for listening item drag events */ public interface OnItemDragEventListener { /** * Callback method to be invoked when dragging is started. * * @param position The position of the item. */ void onItemDragStarted(int position); /** * Callback method to be invoked when item position is changed during drag. * * @param fromPosition The old position of the item. * @param toPosition The new position of the item */ void onItemDragPositionChanged(int fromPosition, int toPosition); /** * Callback method to be invoked when dragging is finished. * * @param fromPosition Previous position of the item. * @param toPosition New position of the item. * @param result Indicates whether the dragging operation was succeeded. */ void onItemDragFinished(int fromPosition, int toPosition, boolean result); /** * Callback method to be invoked when the distance of currently dragging item is updated. * * @param offsetX The horizontal distance of currently dragging item from the initial position in pixels. * @param offsetY The vertical distance of currently dragging item from the initial position in pixels. */ void onItemDragMoveDistanceUpdated(int offsetX, int offsetY); } // -- private static final int SCROLL_DIR_NONE = 0; private static final int SCROLL_DIR_UP = (1 << 0); private static final int SCROLL_DIR_DOWN = (1 << 1); private static final int SCROLL_DIR_LEFT = (1 << 2); private static final int SCROLL_DIR_RIGHT = (1 << 3); private static final boolean LOCAL_LOGV = false; private static final boolean LOCAL_LOGD = false; private static final boolean LOCAL_LOGI = true; private static final float SCROLL_THRESHOLD = 0.3f; // 0.0f < X < 0.5f private static final float SCROLL_AMOUNT_COEFF = 25; private static final float SCROLL_TOUCH_SLOP_MULTIPLY = 1.5f; static class SwapTarget { public RecyclerView.ViewHolder holder; public int position; public boolean self; public void clear() { holder = null; position = RecyclerView.NO_POSITION; self = false; } } static class FindSwapTargetContext { public RecyclerView rv; public DraggingItemInfo draggingItemInfo; public RecyclerView.ViewHolder draggingItem; public int lastTouchX; public int lastTouchY; public int overlayItemLeft; public int overlayItemTop; public int overlayItemLeftNotClipped; public int overlayItemTopNotClipped; public int layoutType; public boolean vertical; public ItemDraggableRange wrappedAdapterRange; public ItemDraggableRange rootAdapterRange; public boolean checkCanSwap; public void setup( RecyclerView rv, RecyclerView.ViewHolder vh, DraggingItemInfo info, int lastTouchX, int lastTouchY, ItemDraggableRange wrappedAdapterPange, ItemDraggableRange rootAdapterRange, boolean checkCanSwap) { this.rv = rv; this.draggingItemInfo = info; this.draggingItem = vh; this.lastTouchX = lastTouchX; this.lastTouchY = lastTouchY; this.wrappedAdapterRange = wrappedAdapterPange; this.rootAdapterRange = rootAdapterRange; this.checkCanSwap = checkCanSwap; this.layoutType = CustomRecyclerViewUtils.getLayoutType(rv); this.vertical = CustomRecyclerViewUtils.extractOrientation(this.layoutType) == CustomRecyclerViewUtils.ORIENTATION_VERTICAL; this.overlayItemLeft = this.overlayItemLeftNotClipped = lastTouchX - info.grabbedPositionX; this.overlayItemTop = this.overlayItemTopNotClipped = lastTouchY - info.grabbedPositionY; if (this.vertical) { this.overlayItemLeft = Math.max(this.overlayItemLeft, rv.getPaddingLeft()); this.overlayItemLeft = Math.min(this.overlayItemLeft, Math.max(0, rv.getWidth() - rv.getPaddingRight() - draggingItemInfo.width)); } else { this.overlayItemTop = Math.max(this.overlayItemTop, rv.getPaddingTop()); this.overlayItemTop = Math.min(this.overlayItemTop, Math.max(0, rv.getHeight() - rv.getPaddingBottom() - draggingItemInfo.height)); } } public void clear() { this.rv = null; this.draggingItemInfo = null; this.draggingItem = null; } } private RecyclerView mRecyclerView; private Interpolator mSwapTargetTranslationInterpolator = DEFAULT_SWAP_TARGET_TRANSITION_INTERPOLATOR; private