圆形片段磨损手表在模拟器/手表中变黑

Question

我在我的Android Wear圆形手表(在正方形上工作)上获得黑屏.两种布局在Android Studio布局设计中都显示正常.

项目测试:

https://bitbucket.org/powder366/motoblack

我使用以下代码:

public class MyFragment extends Fragment {
...
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View contentView = inflater.inflate(R.layout.my_fragment, container, false);
...

布局my_fragment:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/my_fragment"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center"
    android:keepScreenOn="true"
    tools:context=".WearFragment">

<LinearLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="vertical">

    <TextView
        android:id="@+id/text1"
        android:text="Hi1"
        android:layout_gravity="center_horizontal"
        style="@style/UnitsStyle"/>

    <TextView
        android:id="@+id/text2"
        android:text="Hi2"
        android:layout_gravity="center_horizontal"
        style="@style/BaseStyle"/>

    <TextView
        android:id="@+id/text3"
        android:text="Hi3"
        android:layout_gravity="center_horizontal"
        style="@style/UnitsStyle"/>

</LinearLayout>

</LinearLayout>

从以下地方拨打电话:

public class MenuAdapter extends FragmentGridPagerAdapter
...
    public MenuAdapter(Context context, FragmentManager fm, Handler handler) {
    super(fm);
    mContext = context;
    mHandler = handler;
    myFragment = new MyFragment();
}
...
@Override
public Fragment getFragment(int rowNum, int colNum) {
    Log.d(TAG, String.format("getFragment(%d, %d)", rowNum, colNum));

    if(colNum == 0) {
        return myFragment;
    }

    if(colNum == 1) {
        final SecondFragment switchAction = SecondFragment.newInstance(mHandler);
        return switchAction;
    }

    return null;
}
...

这是从:

public class WearActivity extends Activity {
...

private GridViewPager gridViewPager;
private MenuAdapter menuAdapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    Log.d(TAG, "Create(Wear)");
    super.onCreate(savedInstanceState);
    setContentView(R.layout.wear_activity);

    final WatchViewStub stub = (WatchViewStub) findViewById(R.id.watch_view_stub);
    stub.setOnLayoutInflatedListener(new WatchViewStub.OnLayoutInflatedListener() {
        @Override
        public void onLayoutInflated(WatchViewStub stub) {
            menuAdapter = new MenuAdapter(WearActivity.this, getFragmentManager(), mHandler);
            gridViewPager = (GridViewPager) findViewById(R.id.pager);
            gridViewPager.setAdapter(menuAdapter);
        }
    });
}
...

有没有人看过这个或者可以给我一个如何解决它的提示？

更新:

wear_activity.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.wearable.view.WatchViewStub
  xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:app="http://schemas.android.com/apk/res-auto"
  xmlns:tools="http://schemas.android.com/tools"
  android:id="@+id/watch_view_stub"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  app:rectLayout="@layout/rect_activity"
  app:roundLayout="@layout/round_activity"
  tools:context=".WearActivity"
  tools:deviceIds="wear">
</android.support.wearable.view.WatchViewStub>

rect_activity.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:layout_gravity="center"
  tools:deviceIds="wear_square">

<com.xyz.my.ScrollableGridViewPager
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/pager"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:keepScreenOn="true"/>

</FrameLayout>

round_activity.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:tools="http://schemas.android.com/tools"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:layout_gravity="center"
  tools:deviceIds="wear_round">

<com.xyz.my.ScrollableGridViewPager
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/pager"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:keepScreenOn="true"/>

</FrameLayout>

额外信息:

public class ScrollableGridViewPager extends GridViewPager {
...

Answer 1

问题不是那么微不足道,所以我希望我已经很清楚地描述了它.

理由#1:

这个问题的真正原因是该onLayoutInflated(WatchViewStub)方法在圆形设备上被调用两次.

它是第一次rect_activity.xml被夸大时被调用:

WearActivity$1.onLayoutInflated(WatchViewStub) line: 26 
WatchViewStub.inflate() line: 133   
WatchViewStub.onMeasure(int, int) line: 141 
WatchViewStub(View).measure(int, int) line: 16648   

但在此之后,第二次调用此方法是round_activity.xml在onApplyWindowInsets(WindowInsets)调度时新填充的:

WearActivity$1.onLayoutInflated(WatchViewStub) line: 26 
WatchViewStub.inflate() line: 133   
WatchViewStub.onApplyWindowInsets(WindowInsets) line: 112   
WatchViewStub(View).dispatchApplyWindowInsets(WindowInsets) line: 6051  
WatchViewStub(ViewGroup).dispatchApplyWindowInsets(WindowInsets) line: 5435 
SwipeDismissLayout(ViewGroup).dispatchApplyWindowInsets(WindowInsets) line: 5439    
PhoneWindow$DecorView(ViewGroup).dispatchApplyWindowInsets(WindowInsets) line: 5439 
ViewRootImpl.dispatchApplyInsets(View) line: 1170   

我不知道这个问题是仅在模拟器上还是在真实设备上发生,但我认为这应该被报告为wearable-support-lib中的一个错误(在WatchViewStub组件中要准确).任何地方都没有记录这种行为.

理由#2(#1的视觉后果):

上面的问题听起来应该什么都不做......新的布局是膨胀的(所以旧的布局被删除),新的MenuAdapter将被创建(旧的将不再被使用,所以谁关心),这个新创建MenuAdapter应该被设置为新的适配器GridViewPager.一切都应该"重置"所以它应该仍然可以正常工作(除了由于布局膨胀两次而不是一次膨胀的性能问题).

不完全是......因为这是棘手的部分GridViewPager.

我不知道确切的源代码GridViewPager和FragmentGridPagerAdapter,但它似乎是相似ViewPager和FragmentPagerAdapter代码.FragmentPagerAdapter增加了新创建的片段的FragmentManager特别tag是由具有id的的ViewPager给孩子片段和位置:

122    private static String More ...makeFragmentName(int viewId, int index) {
123        return "android:switcher:" + viewId + ":" + index;
124    }

一旦片段被添加到FragmentManager(当前Activity)tag中,将来可以通过此名称引用它.真正的问题是由于onLayoutInflated(WatchViewStub)方法被调用两次而引起的.第一个片段首先创建MenuAdapter并添加到具有id R.id.pager(来自rect_activity.xml)的容器中.然后round_activity.xml膨胀并调用第二个onLayoutInflated(WatchViewStub)调用 - 新的片段在new中创建MenuAdapter并添加到新膨胀GridViewPager的相同id : R.id.pager. 所以第一个片段和第二个想拥有完全相同的tag在FragmentManager.

在标准中,FragmentPagerAdapter如果tag已经存在给定的片段,则FragmentManager它再次附加到它的前一个父级.你可以在这里看到源代码:

50     @Override
51     public Object More ...instantiateItem(View container, int position) {
52         if (mCurTransaction == null) {
53             mCurTransaction = mFragmentManager.beginTransaction();
54         }
55 
56         // Do we already have this fragment?
57         String name = makeFragmentName(container.getId(), position);
58         Fragment fragment = mFragmentManager.findFragmentByTag(name);
59         if (fragment != null) {
60             if (DEBUG) Log.v(TAG, "Attaching item #" + position + ": f=" + fragment);
61             mCurTransaction.attach(fragment);
62         } else {
63             fragment = getItem(position);
64             if (DEBUG) Log.v(TAG, "Adding item #" + position + ": f=" + fragment);
65             mCurTransaction.add(container.getId(), fragment,
66                     makeFragmentName(container.getId(), position));
67         }
68         if (fragment != mCurrentPrimaryItem) {
69             fragment.setMenuVisibility(false);
70         }
71 
72         return fragment;
73     }

所以可能情况类似,并且第一个片段被重用,它被添加到GridViewPager带有id 的第一个片段R.id.pager- 但是这个片段不再存在,所以片段不能附加到任何地方(并显示).这是一个实现的东西,只有一个ViewPager像父亲一样具有给定的id Activity.

对于另外一个实验,我为两者设置了不同的ID GridViewPagers.一个rect_activity.xml有id R.id.pager1,另一个round_activity.xml有`R.id.pager2'.

final WatchViewStub stub = (WatchViewStub) findViewById(R.id.watch_view_stub);
    stub.setOnLayoutInflatedListener(new WatchViewStub.OnLayoutInflatedListener() {
        @Override
        public void onLayoutInflated(WatchViewStub stub) {
            menuAdapter = new MenuAdapter(WearActivity.this, getFragmentManager());
            GridViewPager gridViewPager1 = (GridViewPager) findViewById(R.id.pager1);
            if(gridViewPager1!=null) {          // rect_activity
                gridViewPager1.setAdapter(menuAdapter);
            }

            GridViewPager gridViewPager2 = (GridViewPager) findViewById(R.id.pager2);
            if(gridViewPager2!=null) {          // round_activity
                gridViewPager2.setAdapter(menuAdapter);
            }
        }
    });

仅在第一次传递gridViewPager1中找到并且仅设置其适配器.类似于第二次传递 - 仅gridViewPager2设置了适配器.因为GridViewPagers具有不同的id tags,所以片段中没有冲突,因此最终结果如预期的那样.
但这只是为了证明上面描述的理论:)

解:

WatchViewStub被用于提供不同的布局rect和round屏幕.我可以看到你对两种形状使用完全相同的布局.你可以摆脱它WatchViewStub,只是这样做:

public class WearActivity extends Activity {

    private GridViewPager gridViewPager;
    private MenuAdapter menuAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.rect_activity);

        menuAdapter = new MenuAdapter(WearActivity.this, getFragmentManager());
        gridViewPager = (GridViewPager) findViewById(R.id.pager);
        gridViewPager.setAdapter(menuAdapter);
    }
}

这将使您的示例完美无需使用WatchViewStub.