WindowManager 添加的视图上的 ViewPager 获得 "java.lang.IllegalArgumentException: No view found for id"
ViewPager on a view added by WindowManager getting "java.lang.IllegalArgumentException: No view found for id"
我正在实现一个照片查看器，它允许用户从缩略图以全屏模式查看照片。
我目前的方法是向 WindowManager 添加膨胀视图。在膨胀视图中，有一个 ViewPager 允许用户切换图像。我得到了错误 "java.lang.IllegalArgumentException: No view found for id"
详情如下（视图在setActivity方法中膨胀，viewPager在openPhoto方法中设置适配器）：
public class PhotoViewer {
private static final String TAG = "PhotoViewer";
private Activity parentActivity;
private FrameLayoutTouchListener windowView;
private RelativeLayout containerView;
private WindowManager.LayoutParams windowLayoutParams;
private PhotoViewerAdapter photoAdapter;
private ViewPager viewPager;
public PhotoViewer() {
super();
}
private static volatile PhotoViewer Instance = null;
/*inflate view here*/
public void setParentActivity(Activity activity) {
if (parentActivity == activity) {
return;
}
parentActivity = activity;
windowView = new FrameLayout(activity);
containerView = (RelativeLayout) LayoutInflater.from(activity)
.inflate(R.layout.fragment_photo_viewer, null);
containerView.setFocusable(false);
windowView.addView(containerView);
windowLayoutParams = new WindowManager.LayoutParams();
windowLayoutParams.height = WindowManager.LayoutParams.MATCH_PARENT;
windowLayoutParams.format = PixelFormat.TRANSLUCENT;
windowLayoutParams.width = WindowManager.LayoutParams.MATCH_PARENT;
windowLayoutParams.gravity = Gravity.TOP;
windowLayoutParams.type = WindowManager.LayoutParams.LAST_APPLICATION_WINDOW;
windowLayoutParams.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;
viewPager = (ViewPager) containerView.findViewById(R.id.photo_viewer_view_pager);
}
/*set data and adapter for viewPager here*/
public void openPhoto (PhotoSupporter photoSupporter, int position){
try {
if (windowView.getParent() != null) {
WindowManager wm = (WindowManager) parentActivity.getSystemService(Context.WINDOW_SERVICE);
wm.removeView(windowView);
}
} catch (Exception e) {
Log.v(TAG, e.getMessage());
}
WindowManager wm = (WindowManager) parentActivity.getSystemService(Context.WINDOW_SERVICE);
wm.addView(windowView, windowLayoutParams);
this.photoSupporter = photoSupporter;
photoAdapter = new PhotoViewerAdapter(((FragmentActivity) parentActivity).getSupportFragmentManager(), photoSupporter);
viewPager.storeAdapter(photoAdapter);
viewPager.setCurrentItem(position);
}
/**
* Larger PhotoView
*
*
* **/
public static class PhotoViewerAdapter extends FragmentStatePagerAdapter {
private PhotoSupporter photoSupporter;
public PhotoViewerAdapter(FragmentManager fm, PhotoSupporter photoSupporter) {
super(fm);
this.photoSupporter = photoSupporter;
}
@Override
public Fragment getItem(int position) {
String src = null;
// get photo src
return PhotoViewFragment.newInstance(src);
}
@Override
public int getCount() {
Log.w(TAG, "size in adapter: " + photoSupporter.getSize());
return photoSupporter.getSize();
}
}
public static class PhotoViewFragment extends Fragment {
private String imagePath;
public PhotoViewFragment() {
}
public static PhotoViewFragment newInstance(String imagePath) {
PhotoViewFragment previewFragment = new PhotoViewFragment();
// put data
Bundle bundle = new Bundle();
bundle.putString("IMAGE_PATH",
imagePath);
previewFragment.setArguments(bundle);
return previewFragment;
}
/**
* When creating, retrieve this instance's number from its arguments.
*/
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
imagePath = getArguments() != null ? getArguments().getString(
"IMAGE_PATH") : "";
Log.d("onCreate", imagePath);
}
/**
* The Fragment's UI is just a simple text view showing its instance
* number.
*/
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
ImageView imageView = new ImageView(getActivity());
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams
(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
imageView.setLayoutParams(lp);
// set image by Picasso
Picasso picassoInstance = Picasso.with(getActivity());
picassoInstance.setIndicatorsEnabled(true);
picassoInstance.load(new File(imagePath))
.error(R.drawable.ic_picture_placeholder_light2)
.fit()
.centerInside()
.into(imageView);
return imageView;
}
}
}
这里是调用 PhotoViewer 方法的地方：
public class PhotosFragment extends Fragment implements PhotoSupporter{
/*
....
*/
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
showLoading();
photosGridview = (GridView) findViewById(R.id.group_photos_gridview);
if (listPhotos == null) {
listPhotos = new ArrayList<Photo>();
}
photoListAdapter = new PhotoListAdapter(listPhotos, getActivity());
photosGridview.setAdapter(photoListAdapter);
photosGridview.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
PhotoViewer.getInstance().setParentActivity(getActivity());
PhotoViewer.getInstance().openPhoto(PhotosFragment.this, position);
}
});
}
@Override
public int getSize() {
return listPhotos == null ? 0 : listPhotos.size();
}
@Override
public Photo getPhotoItem(int position) {
return listPhotos.get(position);
}
}
这里是包含 viewPager 的视图布局：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<android.support.v4.view.ViewPager
android:id="@+id/photo_viewer_view_pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/dark_background" >
</android.support.v4.view.ViewPager>
这里是logcat:
01-14 14:12:55.271: E/AndroidRuntime(11435): FATAL EXCEPTION: main
01-14 14:12:55.271: E/AndroidRuntime(11435): java.lang.IllegalArgumentException: No view found for id 0x7f0b00df (com.newsfeed.android:id/photo_viewer_view_pager) for fragment PhotoViewFragment{537b5ec4 #8 id=0x7f0b00df}
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:903)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.ja va:1088)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:461)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentSta tePagerAdapter.java:163)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.view.ViewPager.populate(ViewPager.java:1064)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.view.ViewPager.populate(ViewPager.java:911)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1432)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.View.measure(View.java:15172)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:617)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:399)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.View.measure(View.java:15172)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4814)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.View.measure(View.java:15172)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1848)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1100)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1273)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:998)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4212)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:725)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.Choreographer.doCallbacks(Choreographer.java:555)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.Choreographer.doFrame(Choreographer.java:525)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:711)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.os.Handler.handleCallback(Handler.java:615)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.os.Handler.dispatchMessage(Handler.java:92)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.os.Looper.loop(Looper.java:137)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.app.ActivityThread.main(ActivityThread.java:4745)
01-14 14:12:55.271: E/AndroidRuntime(11435): at java.lang.reflect.Method.invokeNative(Native Method)
01-14 14:12:55.271: E/AndroidRuntime(11435): at java.lang.reflect.Method.invoke(Method.java:511)
01-14 14:12:55.271: E/AndroidRuntime(11435): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
01-14 14:12:55.271: E/AndroidRuntime(11435): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
01-14 14:12:55.271: E/AndroidRuntime(11435): at dalvik.system.NativeStart.main(Native Method)
这个问题有什么解决办法吗？非常感谢你们！
我认为您只是遗漏了一个小错误。而不是这个。
viewPager = (ViewPager) containerView.findViewById(R.id.photo_viewer_view_pager);
做
viewPager = (ViewPager) containerView.findViewById(R.id.photo_viewer_viewpager);
我认为您为 viewpager 使用了错误的 ID。希望能解决您的问题。
我认为您是在 findviewById() 之后在 setParenActivity() 中膨胀视图，这就是它无法获取视图的原因。
我认为这是因为您直接通过 WindowManager 添加了 ViewPager。这样做意味着它不会成为正常 Activity 视图层次结构的一部分（即装饰视图的子级）。 Activity.findViewById（使用装饰视图作为根遍历视图）将无法找到您的 ViewPager。
ViewPager 适配器创建片段并使用 ViewPager (id) 作为容器。创建 Fragment 时，Android 通过 Activity.findViewById 查找此容器，但无法找到它，因此抛出此异常。
听起来您想要某种显示在缩略图网格顶部的视图。您可以只使用 properly styled Dialog(Fragment) 来实现这一点。实施该观点的细节最好作为一个单独的问题提出。
我正在实现一个照片查看器，它允许用户从缩略图以全屏模式查看照片。
我目前的方法是向 WindowManager 添加膨胀视图。在膨胀视图中，有一个 ViewPager 允许用户切换图像。我得到了错误 "java.lang.IllegalArgumentException: No view found for id"
详情如下（视图在setActivity方法中膨胀，viewPager在openPhoto方法中设置适配器）：
public class PhotoViewer {
private static final String TAG = "PhotoViewer";
private Activity parentActivity;
private FrameLayoutTouchListener windowView;
private RelativeLayout containerView;
private WindowManager.LayoutParams windowLayoutParams;
private PhotoViewerAdapter photoAdapter;
private ViewPager viewPager;
public PhotoViewer() {
super();
}
private static volatile PhotoViewer Instance = null;
/*inflate view here*/
public void setParentActivity(Activity activity) {
if (parentActivity == activity) {
return;
}
parentActivity = activity;
windowView = new FrameLayout(activity);
containerView = (RelativeLayout) LayoutInflater.from(activity)
.inflate(R.layout.fragment_photo_viewer, null);
containerView.setFocusable(false);
windowView.addView(containerView);
windowLayoutParams = new WindowManager.LayoutParams();
windowLayoutParams.height = WindowManager.LayoutParams.MATCH_PARENT;
windowLayoutParams.format = PixelFormat.TRANSLUCENT;
windowLayoutParams.width = WindowManager.LayoutParams.MATCH_PARENT;
windowLayoutParams.gravity = Gravity.TOP;
windowLayoutParams.type = WindowManager.LayoutParams.LAST_APPLICATION_WINDOW;
windowLayoutParams.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE;
viewPager = (ViewPager) containerView.findViewById(R.id.photo_viewer_view_pager);
}
/*set data and adapter for viewPager here*/
public void openPhoto (PhotoSupporter photoSupporter, int position){
try {
if (windowView.getParent() != null) {
WindowManager wm = (WindowManager) parentActivity.getSystemService(Context.WINDOW_SERVICE);
wm.removeView(windowView);
}
} catch (Exception e) {
Log.v(TAG, e.getMessage());
}
WindowManager wm = (WindowManager) parentActivity.getSystemService(Context.WINDOW_SERVICE);
wm.addView(windowView, windowLayoutParams);
this.photoSupporter = photoSupporter;
photoAdapter = new PhotoViewerAdapter(((FragmentActivity) parentActivity).getSupportFragmentManager(), photoSupporter);
viewPager.storeAdapter(photoAdapter);
viewPager.setCurrentItem(position);
}
/**
* Larger PhotoView
*
*
* **/
public static class PhotoViewerAdapter extends FragmentStatePagerAdapter {
private PhotoSupporter photoSupporter;
public PhotoViewerAdapter(FragmentManager fm, PhotoSupporter photoSupporter) {
super(fm);
this.photoSupporter = photoSupporter;
}
@Override
public Fragment getItem(int position) {
String src = null;
// get photo src
return PhotoViewFragment.newInstance(src);
}
@Override
public int getCount() {
Log.w(TAG, "size in adapter: " + photoSupporter.getSize());
return photoSupporter.getSize();
}
}
public static class PhotoViewFragment extends Fragment {
private String imagePath;
public PhotoViewFragment() {
}
public static PhotoViewFragment newInstance(String imagePath) {
PhotoViewFragment previewFragment = new PhotoViewFragment();
// put data
Bundle bundle = new Bundle();
bundle.putString("IMAGE_PATH",
imagePath);
previewFragment.setArguments(bundle);
return previewFragment;
}
/**
* When creating, retrieve this instance's number from its arguments.
*/
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
imagePath = getArguments() != null ? getArguments().getString(
"IMAGE_PATH") : "";
Log.d("onCreate", imagePath);
}
/**
* The Fragment's UI is just a simple text view showing its instance
* number.
*/
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
ImageView imageView = new ImageView(getActivity());
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams
(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
imageView.setLayoutParams(lp);
// set image by Picasso
Picasso picassoInstance = Picasso.with(getActivity());
picassoInstance.setIndicatorsEnabled(true);
picassoInstance.load(new File(imagePath))
.error(R.drawable.ic_picture_placeholder_light2)
.fit()
.centerInside()
.into(imageView);
return imageView;
}
}
}
这里是调用 PhotoViewer 方法的地方：
public class PhotosFragment extends Fragment implements PhotoSupporter{
/*
....
*/
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
showLoading();
photosGridview = (GridView) findViewById(R.id.group_photos_gridview);
if (listPhotos == null) {
listPhotos = new ArrayList<Photo>();
}
photoListAdapter = new PhotoListAdapter(listPhotos, getActivity());
photosGridview.setAdapter(photoListAdapter);
photosGridview.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
PhotoViewer.getInstance().setParentActivity(getActivity());
PhotoViewer.getInstance().openPhoto(PhotosFragment.this, position);
}
});
}
@Override
public int getSize() {
return listPhotos == null ? 0 : listPhotos.size();
}
@Override
public Photo getPhotoItem(int position) {
return listPhotos.get(position);
}
}
这里是包含 viewPager 的视图布局：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<android.support.v4.view.ViewPager
android:id="@+id/photo_viewer_view_pager"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/dark_background" >
</android.support.v4.view.ViewPager>
这里是logcat:
01-14 14:12:55.271: E/AndroidRuntime(11435): FATAL EXCEPTION: main
01-14 14:12:55.271: E/AndroidRuntime(11435): java.lang.IllegalArgumentException: No view found for id 0x7f0b00df (com.newsfeed.android:id/photo_viewer_view_pager) for fragment PhotoViewFragment{537b5ec4 #8 id=0x7f0b00df}
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:903)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.ja va:1088)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:461)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.app.FragmentStatePagerAdapter.finishUpdate(FragmentSta tePagerAdapter.java:163)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.view.ViewPager.populate(ViewPager.java:1064)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.view.ViewPager.populate(ViewPager.java:911)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1432)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.View.measure(View.java:15172)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:617)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:399)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.View.measure(View.java:15172)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4814)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.View.measure(View.java:15172)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1848)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1100)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1273)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:998)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4212)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:725)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.Choreographer.doCallbacks(Choreographer.java:555)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.Choreographer.doFrame(Choreographer.java:525)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:711)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.os.Handler.handleCallback(Handler.java:615)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.os.Handler.dispatchMessage(Handler.java:92)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.os.Looper.loop(Looper.java:137)
01-14 14:12:55.271: E/AndroidRuntime(11435): at android.app.ActivityThread.main(ActivityThread.java:4745)
01-14 14:12:55.271: E/AndroidRuntime(11435): at java.lang.reflect.Method.invokeNative(Native Method)
01-14 14:12:55.271: E/AndroidRuntime(11435): at java.lang.reflect.Method.invoke(Method.java:511)
01-14 14:12:55.271: E/AndroidRuntime(11435): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
01-14 14:12:55.271: E/AndroidRuntime(11435): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
01-14 14:12:55.271: E/AndroidRuntime(11435): at dalvik.system.NativeStart.main(Native Method)
这个问题有什么解决办法吗？非常感谢你们！
我认为您只是遗漏了一个小错误。而不是这个。
viewPager = (ViewPager) containerView.findViewById(R.id.photo_viewer_view_pager);
做
viewPager = (ViewPager) containerView.findViewById(R.id.photo_viewer_viewpager);
我认为您为 viewpager 使用了错误的 ID。希望能解决您的问题。
我认为您是在 findviewById() 之后在 setParenActivity() 中膨胀视图，这就是它无法获取视图的原因。
我认为这是因为您直接通过 WindowManager 添加了 ViewPager。这样做意味着它不会成为正常 Activity 视图层次结构的一部分（即装饰视图的子级）。 Activity.findViewById（使用装饰视图作为根遍历视图）将无法找到您的 ViewPager。
ViewPager 适配器创建片段并使用 ViewPager (id) 作为容器。创建 Fragment 时，Android 通过 Activity.findViewById 查找此容器，但无法找到它，因此抛出此异常。
听起来您想要某种显示在缩略图网格顶部的视图。您可以只使用 properly styled Dialog(Fragment) 来实现这一点。实施该观点的细节最好作为一个单独的问题提出。