| /* |
| * Copyright 2017 The Android Open Source Project |
| * |
| * 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 androidx.recyclerview.selection; |
| |
| import static android.support.v4.util.Preconditions.checkArgument; |
| |
| import android.support.v7.widget.RecyclerView; |
| import android.support.v7.widget.RecyclerView.OnItemTouchListener; |
| import android.view.GestureDetector; |
| import android.view.MotionEvent; |
| |
| /** |
| * A class responsible for routing MotionEvents to tool-type specific handlers, |
| * and if not handled by a handler, on to a {@link GestureDetector} for further |
| * processing. |
| * |
| * <p>TouchEventRouter takes its name from |
| * {@link RecyclerView#addOnItemTouchListener(OnItemTouchListener)}. Despite "Touch" |
| * being in the name, it receives MotionEvents for all types of tools. |
| */ |
| final class TouchEventRouter implements OnItemTouchListener { |
| |
| private static final String TAG = "TouchEventRouter"; |
| |
| private final GestureDetector mDetector; |
| private final ToolHandlerRegistry<OnItemTouchListener> mDelegates; |
| |
| TouchEventRouter(GestureDetector detector, OnItemTouchListener defaultDelegate) { |
| checkArgument(detector != null); |
| checkArgument(defaultDelegate != null); |
| |
| mDetector = detector; |
| mDelegates = new ToolHandlerRegistry<>(defaultDelegate); |
| } |
| |
| TouchEventRouter(GestureDetector detector) { |
| this( |
| detector, |
| // Supply a fallback listener does nothing...because the caller |
| // didn't supply a fallback. |
| new OnItemTouchListener() { |
| @Override |
| public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) { |
| return false; |
| } |
| |
| @Override |
| public void onTouchEvent(RecyclerView rv, MotionEvent e) { |
| } |
| |
| @Override |
| public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) { |
| } |
| }); |
| } |
| |
| /** |
| * @param toolType See MotionEvent for details on available types. |
| * @param delegate An {@link OnItemTouchListener} to receive events |
| * of {@code toolType}. |
| */ |
| void register(int toolType, OnItemTouchListener delegate) { |
| checkArgument(delegate != null); |
| mDelegates.set(toolType, delegate); |
| } |
| |
| @Override |
| public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) { |
| boolean handled = mDelegates.get(e).onInterceptTouchEvent(rv, e); |
| |
| // Forward all events to UserInputHandler. |
| // This is necessary since UserInputHandler needs to always see the first DOWN event. Or |
| // else all future UP events will be tossed. |
| handled |= mDetector.onTouchEvent(e); |
| |
| return handled; |
| } |
| |
| @Override |
| public void onTouchEvent(RecyclerView rv, MotionEvent e) { |
| mDelegates.get(e).onTouchEvent(rv, e); |
| |
| // Note: even though this event is being handled as part of gestures such as drag and band, |
| // continue forwarding to the GestureDetector. The detector needs to see the entire cluster |
| // of events in order to properly interpret other gestures, such as long press. |
| mDetector.onTouchEvent(e); |
| } |
| |
| @Override |
| public void onRequestDisallowInterceptTouchEvent(boolean disallowIntercept) {} |
| } |