163d2846409d84487d4856d3b8d18cc4684352e29Steve McKay/* 263d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * Copyright 2017 The Android Open Source Project 363d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * 463d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * Licensed under the Apache License, Version 2.0 (the "License"); 563d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * you may not use this file except in compliance with the License. 663d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * You may obtain a copy of the License at 763d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * 863d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * http://www.apache.org/licenses/LICENSE-2.0 963d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * 1063d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * Unless required by applicable law or agreed to in writing, software 1163d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * distributed under the License is distributed on an "AS IS" BASIS, 1263d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 1363d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * See the License for the specific language governing permissions and 1463d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * limitations under the License. 1563d2846409d84487d4856d3b8d18cc4684352e29Steve McKay */ 1663d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 172a32c7e1264b14a20ed900abadea828b804a46ceAurimas Liutikaspackage androidx.recyclerview.selection; 1863d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 19ac5fe7c617c66850fff75a9fce9979c6e5674b0fAurimas Liutikasimport static androidx.core.util.Preconditions.checkArgument; 20ac5fe7c617c66850fff75a9fce9979c6e5674b0fAurimas Liutikasimport static androidx.core.util.Preconditions.checkState; 2163d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 2260dadaeed4f5cee272b575dfde6c02e3506a2fa0Aurimas Liutikasimport android.view.MotionEvent; 2360dadaeed4f5cee272b575dfde6c02e3506a2fa0Aurimas Liutikas 24ac5fe7c617c66850fff75a9fce9979c6e5674b0fAurimas Liutikasimport androidx.annotation.NonNull; 25ac5fe7c617c66850fff75a9fce9979c6e5674b0fAurimas Liutikasimport androidx.annotation.Nullable; 2663d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 2763d2846409d84487d4856d3b8d18cc4684352e29Steve McKayimport java.util.Arrays; 2863d2846409d84487d4856d3b8d18cc4684352e29Steve McKayimport java.util.List; 2963d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 3063d2846409d84487d4856d3b8d18cc4684352e29Steve McKay/** 317fb763509e07f98d650efc25c91bff8b1cb239acSteve McKay * Registry for tool specific event handler. This provides map like functionality, 327fb763509e07f98d650efc25c91bff8b1cb239acSteve McKay * along with fallback to a default handler, while avoiding auto-boxing of tool 337fb763509e07f98d650efc25c91bff8b1cb239acSteve McKay * type values that would be necessitated where a Map used. 347fb763509e07f98d650efc25c91bff8b1cb239acSteve McKay * 357fb763509e07f98d650efc25c91bff8b1cb239acSteve McKay * @param <T> type of item being registered. 3663d2846409d84487d4856d3b8d18cc4684352e29Steve McKay */ 3763d2846409d84487d4856d3b8d18cc4684352e29Steve McKayfinal class ToolHandlerRegistry<T> { 3863d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 3963d2846409d84487d4856d3b8d18cc4684352e29Steve McKay // Currently there are four known input types. ERASER is the last one, so has the 4063d2846409d84487d4856d3b8d18cc4684352e29Steve McKay // highest value. UNKNOWN is zero, so we add one. This allows delegates to be 4163d2846409d84487d4856d3b8d18cc4684352e29Steve McKay // registered by type, and avoid the auto-boxing that would be necessary were we 4263d2846409d84487d4856d3b8d18cc4684352e29Steve McKay // to store delegates in a Map<Integer, Delegate>. 43f8a82a95a1a962ec05536f7196fcee0f1384a497Jake Wharton private static final int NUM_INPUT_TYPES = MotionEvent.TOOL_TYPE_ERASER + 1; 4463d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 4563d2846409d84487d4856d3b8d18cc4684352e29Steve McKay private final List<T> mHandlers = Arrays.asList(null, null, null, null, null); 4663d2846409d84487d4856d3b8d18cc4684352e29Steve McKay private final T mDefault; 4763d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 487fb763509e07f98d650efc25c91bff8b1cb239acSteve McKay ToolHandlerRegistry(@NonNull T defaultDelegate) { 4963d2846409d84487d4856d3b8d18cc4684352e29Steve McKay checkArgument(defaultDelegate != null); 5063d2846409d84487d4856d3b8d18cc4684352e29Steve McKay mDefault = defaultDelegate; 5163d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 5263d2846409d84487d4856d3b8d18cc4684352e29Steve McKay // Initialize all values to null. 53f8a82a95a1a962ec05536f7196fcee0f1384a497Jake Wharton for (int i = 0; i < NUM_INPUT_TYPES; i++) { 5463d2846409d84487d4856d3b8d18cc4684352e29Steve McKay mHandlers.set(i, null); 5563d2846409d84487d4856d3b8d18cc4684352e29Steve McKay } 5663d2846409d84487d4856d3b8d18cc4684352e29Steve McKay } 5763d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 5863d2846409d84487d4856d3b8d18cc4684352e29Steve McKay /** 5963d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * @param toolType 6063d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * @param delegate the delegate, or null to unregister. 6163d2846409d84487d4856d3b8d18cc4684352e29Steve McKay * @throws IllegalStateException if an tooltype handler is already registered. 6263d2846409d84487d4856d3b8d18cc4684352e29Steve McKay */ 6363d2846409d84487d4856d3b8d18cc4684352e29Steve McKay void set(int toolType, @Nullable T delegate) { 6463d2846409d84487d4856d3b8d18cc4684352e29Steve McKay checkArgument(toolType >= 0 && toolType <= MotionEvent.TOOL_TYPE_ERASER); 6563d2846409d84487d4856d3b8d18cc4684352e29Steve McKay checkState(mHandlers.get(toolType) == null); 6663d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 6763d2846409d84487d4856d3b8d18cc4684352e29Steve McKay mHandlers.set(toolType, delegate); 6863d2846409d84487d4856d3b8d18cc4684352e29Steve McKay } 6963d2846409d84487d4856d3b8d18cc4684352e29Steve McKay 707fb763509e07f98d650efc25c91bff8b1cb239acSteve McKay T get(@NonNull MotionEvent e) { 7163d2846409d84487d4856d3b8d18cc4684352e29Steve McKay T d = mHandlers.get(e.getToolType(0)); 7263d2846409d84487d4856d3b8d18cc4684352e29Steve McKay return d != null ? d : mDefault; 7363d2846409d84487d4856d3b8d18cc4684352e29Steve McKay } 7463d2846409d84487d4856d3b8d18cc4684352e29Steve McKay} 75