content: /*
   * Copyright (C) 2015 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 android.widget;
  
  import android.annotation.NonNull;
  import android.content.Context;
  import android.content.res.Configuration;
  import android.content.res.Resources;
  import android.transition.Transition;
  import android.util.AttributeSet;
  import android.view.KeyEvent;
  import android.view.MenuItem;
  import android.view.MotionEvent;
  import android.view.View;
  
  import com.android.internal.view.menu.ListMenuItemView;
  import com.android.internal.view.menu.MenuAdapter;
  import com.android.internal.view.menu.MenuBuilder;
  
  /**
   * A MenuPopupWindow represents the popup window for menu.
   *
   * MenuPopupWindow is mostly same as ListPopupWindow, but it has customized
   * behaviors specific to menus,
   *
   * @hide
   */
  public class MenuPopupWindow extends ListPopupWindow implements MenuItemHoverListener {
      private MenuItemHoverListener mHoverListener;
  
      public MenuPopupWindow(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
          super(context, attrs, defStyleAttr, defStyleRes);
      }
  
      @Override
      DropDownListView createDropDownListView(Context context, boolean hijackFocus) {
          MenuDropDownListView view = new MenuDropDownListView(context, hijackFocus);
          view.setHoverListener(this);
          return view;
      }
  
      public void setEnterTransition(Transition enterTransition) {
          mPopup.setEnterTransition(enterTransition);
      }
  
      public void setExitTransition(Transition exitTransition) {
          mPopup.setExitTransition(exitTransition);
      }
  
      public void setHoverListener(MenuItemHoverListener hoverListener) {
          mHoverListener = hoverListener;
      }
  
      /**
       * Set whether this window is touch modal or if outside touches will be sent to
       * other windows behind it.
       */
      public void setTouchModal(boolean touchModal) {
          mPopup.setTouchModal(touchModal);
      }
  
      @Override
      public void onItemHoverEnter(@NonNull MenuBuilder menu, @NonNull MenuItem item) {
          // Forward up the chain
          if (mHoverListener != null) {
              mHoverListener.onItemHoverEnter(menu, item);
          }
      }
  
      @Override
      public void onItemHoverExit(@NonNull MenuBuilder menu, @NonNull MenuItem item) {
          // Forward up the chain
          if (mHoverListener != null) {
              mHoverListener.onItemHoverExit(menu, item);
          }
      }
  
      /**
       * @hide
       */
      public static class MenuDropDownListView extends DropDownListView {
          final int mAdvanceKey;
          final int mRetreatKey;
  
          private MenuItemHoverListener mHoverListener;
          private MenuItem mHoveredMenuItem;
  
          public MenuDropDownListView(Context context, boolean hijackFocus) {
              super(context, hijackFocus);
  
              final Resources res = context.getResources();
              final Configuration config = res.getConfiguration();
              if (config.getLayoutDirection() == View.LAYOUT_DIRECTION_RTL) {
                  mAdvanceKey = KeyEvent.KEYCODE_DPAD_LEFT;
                  mRetreatKey = KeyEvent.KEYCODE_DPAD_RIGHT;
              } else {
                  mAdvanceKey = KeyEvent.KEYCODE_DPAD_RIGHT;
                  mRetreatKey = KeyEvent.KEYCODE_DPAD_LEFT;
              }
          }
  
          public void setHoverListener(MenuItemHoverListener hoverListener) {
              mHoverListener = hoverListener;
          }
  
          public void clearSelection() {
              setSelectedPositionInt(INVALID_POSITION);
              setNextSelectedPositionInt(INVALID_POSITION);
          }
  
          @Override
          public boolean onKeyDown(int keyCode, KeyEvent event) {
              ListMenuItemView selectedItem = (ListMenuItemView) getSelectedView();
              if (selectedItem != null && keyCode == mAdvanceKey) {
                  if (selectedItem.isEnabled() && selectedItem.getItemData().hasSubMenu()) {
                      performItemClick(
                              selectedItem,
                              getSelectedItemPosition(),
                              getSelectedItemId());
                  }
                  return true;
              } else if (selectedItem != null && keyCode == mRetreatKey) {
                  setSelectedPositionInt(INVALID_POSITION);
                  setNextSelectedPositionInt(INVALID_POSITION);
  
                  // Close only the top-level menu.
                  ((MenuAdapter) getAdapter()).getAdapterMenu().close(false /* closeAllMenus */);
                  return true;
              }
              return super.onKeyDown(keyCode, event);
          }
  
          @Override
          public boolean onHoverEvent(MotionEvent ev) {
              // Dispatch any changes in hovered item index to the listener.
              if (mHoverListener != null) {
                  // The adapter may be wrapped. Adjust the index if necessary.
                  final int headersCount;
                  final MenuAdapter menuAdapter;
                  final ListAdapter adapter = getAdapter();
                  if (adapter instanceof HeaderViewListAdapter) {
                      final HeaderViewListAdapter headerAdapter = (HeaderViewListAdapter) adapter;
                      headersCount = headerAdapter.getHeadersCount();
                      menuAdapter = (MenuAdapter) headerAdapter.getWrappedAdapter();
                  } else {
                      headersCount = 0;
                      menuAdapter = (MenuAdapter) adapter;
                  }
  
                  // Find the menu item for the view at the event coordinates.
                  MenuItem menuItem = null;
                  if (ev.getAction() != MotionEvent.ACTION_HOVER_EXIT) {
                      final int position = pointToPosition((int) ev.getX(), (int) ev.getY());
                      if (position != INVALID_POSITION) {
                          final int itemPosition = position - headersCount;
                          if (itemPosition >= 0 && itemPosition < menuAdapter.getCount()) {
                              menuItem = menuAdapter.getItem(itemPosition);
                          }
                      }
                  }
  
                  final MenuItem oldMenuItem = mHoveredMenuItem;
                  if (oldMenuItem != menuItem) {
                      final MenuBuilder menu = menuAdapter.getAdapterMenu();
                      if (oldMenuItem != null) {
                          mHoverListener.onItemHoverExit(menu, oldMenuItem);
                      }
  
                      mHoveredMenuItem = menuItem;
  
                      if (menuItem != null) {
                          mHoverListener.onItemHoverEnter(menu, menuItem);
                      }
                  }
              }
  
              return super.onHoverEvent(ev);
          }
      }
  }