content: /*
   * Copyright (C) 2019 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 com.android.launcher3.touch;
  
  import android.content.Context;
  import android.graphics.PointF;
  import android.view.MotionEvent;
  import android.view.ViewConfiguration;
  
  import androidx.annotation.NonNull;
  import androidx.annotation.VisibleForTesting;
  
  import com.android.launcher3.Utilities;
  
  /**
   * Two dimensional scroll/drag/swipe gesture detector that reports x and y displacement/velocity.
   */
  public class BothAxesSwipeDetector extends BaseSwipeDetector {
  
      public static final int DIRECTION_UP = 1 << 0;
      // Note that this will track left instead of right in RTL.
      public static final int DIRECTION_RIGHT = 1 << 1;
      public static final int DIRECTION_DOWN = 1 << 2;
      // Note that this will track right instead of left in RTL.
      public static final int DIRECTION_LEFT = 1 << 3;
  
      /* Client of this gesture detector can register a callback. */
      private final Listener mListener;
  
      private int mScrollDirections;
  
      public BothAxesSwipeDetector(@NonNull Context context, @NonNull Listener l) {
          this(ViewConfiguration.get(context), l, Utilities.isRtl(context.getResources()));
      }
  
      @VisibleForTesting
      protected BothAxesSwipeDetector(@NonNull ViewConfiguration config, @NonNull Listener l,
              boolean isRtl) {
          super(config, isRtl);
          mListener = l;
      }
  
      public void setDetectableScrollConditions(int scrollDirectionFlags, boolean ignoreSlop) {
          mScrollDirections = scrollDirectionFlags;
          mIgnoreSlopWhenSettling = ignoreSlop;
      }
  
      @Override
      protected boolean shouldScrollStart(PointF displacement) {
          // Check if the client is interested in scroll in current direction.
          boolean canScrollUp = (mScrollDirections & DIRECTION_UP) > 0
                  && displacement.y <= -mTouchSlop;
          boolean canScrollRight = (mScrollDirections & DIRECTION_RIGHT) > 0
                  && displacement.x >= mTouchSlop;
          boolean canScrollDown = (mScrollDirections & DIRECTION_DOWN) > 0
                  && displacement.y >= mTouchSlop;
          boolean canScrollLeft = (mScrollDirections & DIRECTION_LEFT) > 0
                  && displacement.x <= -mTouchSlop;
          return canScrollUp || canScrollRight || canScrollDown || canScrollLeft;
      }
  
      @Override
      protected void reportDragStartInternal(boolean recatch) {
          mListener.onDragStart(!recatch);
      }
  
      @Override
      protected void reportDraggingInternal(PointF displacement, MotionEvent event) {
          mListener.onDrag(displacement, event);
      }
  
      @Override
      protected void reportDragEndInternal(PointF velocity) {
          mListener.onDragEnd(velocity);
      }
  
      /** Listener to receive updates on the swipe. */
      public interface Listener {
          /** @param start whether this was the original drag start, as opposed to a recatch. */
          void onDragStart(boolean start);
  
          boolean onDrag(PointF displacement, MotionEvent motionEvent);
  
          void onDragEnd(PointF velocity);
      }
  }
  