ViewPager 不显示视图

Question

我创建了一个没有片段的视图寻呼机。

这是我的适配器class

public class CustomPagerAdapter extends PagerAdapter {
private ArrayList<POJOThingsToFocus> thingsToFocusArrayList;
private ImageLoader imageLoader;
private ImageLoadingListener animateFirstListener = new AnimateFirstDisplayListener();
private DisplayImageOptions options;
public CustomPagerAdapter(ArrayList<POJOThingsToFocus> thingsToFocusArrayList) {
    this.thingsToFocusArrayList=thingsToFocusArrayList;
    options = new DisplayImageOptions.Builder()
            .showImageOnLoading(R.mipmap.ic_launcher)
            .cacheInMemory(true)
            .cacheOnDisk(true)
            .considerExifParams(true)
            .build();
}

@Override
public int getCount() {
    return thingsToFocusArrayList.size();
}

@Override
public Object instantiateItem(ViewGroup container, int position) {
    LayoutInflater mInflater = (LayoutInflater)
            container.getContext().getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
    View layout = mInflater.inflate(R.layout.element_things_to_focus, null);
    ImageView ivThingsToFocus = (ImageView) layout.findViewById(R.id.imageViewThingsToFocus);
    TextView tvvThingsToFocus = (TextView) layout.findViewById(R.id.textViewThingsToFocus);
    imageLoader = ImageLoader.getInstance();;
    if (!imageLoader.isInited()) {
        imageLoader.init(ImageLoaderConfiguration.createDefault( container.getContext()));
    }
    imageLoader.displayImage(thingsToFocusArrayList.get(position).getThingsToFocusImage(), ivThingsToFocus, options, animateFirstListener);
    tvvThingsToFocus.setText(thingsToFocusArrayList.get(position).getThingsToFocusDescription());
    container.addView(layout);
    return container;
}

@Override
public void destroyItem(ViewGroup container, int position, Object object) {
    container.removeView((View) object);
}


@Override
public boolean isViewFromObject(View container, Object obj) {
    return container == obj;
}

private static class AnimateFirstDisplayListener extends SimpleImageLoadingListener {

    static final List<String> displayedImages = Collections.synchronizedList(new LinkedList<String>());

    @Override
    public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
        if (loadedImage != null) {
            ImageView imageView = (ImageView) view;
            boolean firstDisplay = !displayedImages.contains(imageUri);
            if (firstDisplay) {
                FadeInBitmapDisplayer.animate(imageView, 500);
                displayedImages.add(imageUri);
            }
        }
    }
}
}

这是我正在充气的布局

LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:orientation="vertical">

<ImageView
    android:id="@+id/imageViewThingsToFocus"
    android:layout_width="wrap_content"
    android:src="@mipmap/ic_launcher"
    android:layout_height="wrap_content" />

<TextView
    android:id="@+id/textViewThingsToFocus"
    android:layout_width="match_parent"
    android:textColor="@android:color/black"
    android:text="xxxxx"
    android:layout_height="wrap_content" />
</LinearLayout>

但是我在屏幕上看不到任何视图。我可以滑动但是没有显示。

这是我设置适配器的方式

thingsToFocusArrayList = new ArrayList<>();
                    thingsToFocusArrayList.add(new POJOThingsToFocus(1,"https://1800hocking.files.wordpress.com/2011/07/hi-ohio-logo.jpg","Hey 1"));
                    thingsToFocusArrayList.add(new POJOThingsToFocus(2,"https://1800hocking.files.wordpress.com/2011/07/hi-ohio-logo.jpg","Hey 2"));
                    thingsToFocusArrayList.add(new POJOThingsToFocus(3,"https://1800hocking.files.wordpress.com/2011/07/hi-ohio-logo.jpg","Hey 3"));
                    thingsToFocusArrayList.add(new POJOThingsToFocus(4,"https://1800hocking.files.wordpress.com/2011/07/hi-ohio-logo.jpg","Hey 4"));

                    viewPager.setAdapter(new CustomPagerAdapter(thingsToFocusArrayList));

Answer 1

已解决

刚好需要

retrun  layout;

而不是

retrun  container;

ViewPager 不显示视图

ViewPager not showing the views

android

android-viewpager

android-pageradapter