| /* |
| * Copyright (C) 2013 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.support.v4.widget; |
| |
| import android.support.annotation.RequiresApi; |
| import android.os.Build; |
| import android.view.View; |
| import android.view.View.OnTouchListener; |
| |
| /** |
| * Helper for accessing features in ListPopupWindow introduced after API level 4 |
| * in a backwards compatible fashion. |
| */ |
| public final class ListPopupWindowCompat { |
| /** |
| * Interface for the full API. |
| */ |
| interface ListPopupWindowImpl { |
| public OnTouchListener createDragToOpenListener(Object listPopupWindow, View src); |
| } |
| |
| /** |
| * Interface implementation that doesn't use anything above v4 APIs. |
| */ |
| static class BaseListPopupWindowImpl implements ListPopupWindowImpl { |
| @Override |
| public OnTouchListener createDragToOpenListener(Object listPopupWindow, View src) { |
| return null; |
| } |
| } |
| |
| /** |
| * Interface implementation for devices with at least KitKat APIs. |
| */ |
| @RequiresApi(19) |
| static class KitKatListPopupWindowImpl extends BaseListPopupWindowImpl { |
| @Override |
| public OnTouchListener createDragToOpenListener(Object listPopupWindow, View src) { |
| return ListPopupWindowCompatKitKat.createDragToOpenListener(listPopupWindow, src); |
| } |
| } |
| |
| /** |
| * Select the correct implementation to use for the current platform. |
| */ |
| static final ListPopupWindowImpl IMPL; |
| static { |
| if (Build.VERSION.SDK_INT >= 19) { |
| IMPL = new KitKatListPopupWindowImpl(); |
| } else { |
| IMPL = new BaseListPopupWindowImpl(); |
| } |
| } |
| |
| private ListPopupWindowCompat() { |
| // This class is not publicly instantiable. |
| } |
| |
| /** |
| * On API {@link android.os.Build.VERSION_CODES#KITKAT} and higher, returns |
| * an {@link OnTouchListener} that can be added to the source view to |
| * implement drag-to-open behavior. Generally, the source view should be the |
| * same view that was passed to ListPopupWindow.setAnchorView(View). |
| * <p> |
| * When the listener is set on a view, touching that view and dragging |
| * outside of its bounds will open the popup window. Lifting will select the |
| * currently touched list item. |
| * <p> |
| * Example usage: |
| * |
| * <pre> |
| * ListPopupWindow myPopup = new ListPopupWindow(context); |
| * myPopup.setAnchor(myAnchor); |
| * OnTouchListener dragListener = myPopup.createDragToOpenListener(myAnchor); |
| * myAnchor.setOnTouchListener(dragListener); |
| * </pre> |
| * |
| * @param listPopupWindow the ListPopupWindow against which to invoke the |
| * method |
| * @param src the view on which the resulting listener will be set |
| * @return a touch listener that controls drag-to-open behavior, or null on |
| * unsupported APIs |
| */ |
| public static OnTouchListener createDragToOpenListener(Object listPopupWindow, View src) { |
| return IMPL.createDragToOpenListener(listPopupWindow, src); |
| } |
| } |