1/*
2 * Copyright (C) 2013 DroidDriver committers
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.google.android.droiddriver.scroll;
18
19import android.app.UiAutomation;
20import android.widget.ProgressBar;
21
22import com.google.android.droiddriver.DroidDriver;
23import com.google.android.droiddriver.finders.By;
24import com.google.android.droiddriver.finders.Finder;
25import com.google.android.droiddriver.scroll.Direction.Axis;
26import com.google.android.droiddriver.scroll.Direction.DirectionConverter;
27import com.google.android.droiddriver.scroll.Direction.PhysicalDirection;
28
29/**
30 * Static utility classes and methods pertaining to {@link Scroller} instances.
31 */
32public class Scrollers {
33  /**
34   * Augments the delegate {@link ScrollStepStrategy) - after a successful
35   * scroll, waits until ProgressBar is gone.
36   */
37  public static abstract class ProgressBarScrollStepStrategy extends ForwardingScrollStepStrategy {
38    @Override
39    public boolean scroll(DroidDriver driver, Finder containerFinder, PhysicalDirection direction) {
40      if (super.scroll(driver, containerFinder, direction)) {
41        driver.checkGone(By.className(ProgressBar.class));
42        return true;
43      }
44      return false;
45    }
46
47    /** Convenience method to wrap {@code delegate} with this class */
48    public static ScrollStepStrategy wrap(final ScrollStepStrategy delegate) {
49      return new ProgressBarScrollStepStrategy() {
50        @Override
51        protected ScrollStepStrategy delegate() {
52          return delegate;
53        }
54      };
55    }
56  }
57
58  /**
59   * Returns a new default Scroller that works in simple cases. In complex cases
60   * you may try a {@link StepBasedScroller} with a custom
61   * {@link ScrollStepStrategy}:
62   * <ul>
63   * <li>If the Scroller is used with InstrumentationDriver,
64   * StaticSentinelStrategy may work and it's the simplest.</li>
65   * <li>Otherwise, DynamicSentinelStrategy should work in all cases, including
66   * the case of dynamic list, which shows more items when scrolling beyond the
67   * end. On the other hand, it's complex and needs more configuration.</li>
68   * </ul>
69   * Note if a {@link StepBasedScroller} is returned, it is constructed with
70   * arguments that apply to typical cases. You may want to customize them for
71   * specific cases. For instance, {@code perScrollTimeoutMillis} can be 0L if
72   * there are no asynchronously updated views. To that extent, this method
73   * serves as an example of how to construct {@link Scroller}s rather than
74   * providing the "official" {@link Scroller}.
75   */
76  public static Scroller newScroller(UiAutomation uiAutomation) {
77    if (uiAutomation != null) {
78      return new StepBasedScroller(100/* maxScrolls */, 1000L/* perScrollTimeoutMillis */,
79          Axis.VERTICAL, new AccessibilityEventScrollStepStrategy(uiAutomation, 1000L,
80              DirectionConverter.STANDARD_CONVERTER), true/* startFromBeginning */);
81    }
82    // TODO: A {@link Scroller} that directly jumps to the view if an
83    // InstrumentationDriver is used.
84    return new StepBasedScroller(100/* maxScrolls */, 1000L/* perScrollTimeoutMillis */,
85        Axis.VERTICAL, StaticSentinelStrategy.DEFAULT, true/* startFromBeginning */);
86  }
87}
88