android - 为什么当我将 Viewpager 用作 Slider 时，我的应用程序会崩溃

Question

我创建了一个 viewpager 作为滑块，我在其中加载图像和视频。作为单独的项目，它可以正常工作并显示所有图像和视频，但是当我将它作为回收器视图适配器中的视图添加到我的主项目时，我的应用程序会因以下日志而崩溃：

    Process: com.example.koohestantest1.tak, PID: 5205
    java.lang.IllegalStateException: The application's PagerAdapter changed the adapter's contents without calling PagerAdapter#notifyDataSetChanged! Expected adapter item count: 1, found: 2 Pager id: com.example.koohestantest1.tak:id/ps_newsItem Pager class: class androidx.viewpager.widget.ViewPager Problematic adapter: class com.example.koohestantest1.classDirectory.NewsLetterViewPagerAdapter
        at androidx.viewpager.widget.ViewPager.populate(ViewPager.java:1143)
        at androidx.viewpager.widget.ViewPager.populate(ViewPager.java:1092)
        at androidx.viewpager.widget.ViewPager.onMeasure(ViewPager.java:1622)
        at android.view.View.measure(View.java:19858)
        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6083)
        at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1464)
        at android.widget.LinearLayout.measureVertical(LinearLayout.java:758)
        at android.widget.LinearLayout.onMeasure(LinearLayout.java:640)
        at android.view.View.measure(View.java:19858)
        at androidx.core.widget.NestedScrollView.measureChildWithMargins(NestedScrollView.java:1599)
        at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
        at androidx.core.widget.NestedScrollView.onMeasure(NestedScrollView.java:585)
        at android.view.View.measure(View.java:19858)
        at androidx.recyclerview.widget.RecyclerView$LayoutManager.measureChildWithMargins(RecyclerView.java:9678)
        at androidx.recyclerview.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1657)
        at androidx.recyclerview.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1591)
        at androidx.recyclerview.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:668)
        at androidx.recyclerview.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:4309)
        at androidx.recyclerview.widget.RecyclerView.dispatchLayout(RecyclerView.java:4012)
        at androidx.recyclerview.widget.RecyclerView.onLayout(RecyclerView.java:4578)
        at android.view.View.layout(View.java:17638)
        at android.view.ViewGroup.layout(ViewGroup.java:5575)
        at androidx.constraintlayout.widget.ConstraintLayout.onLayout(ConstraintLayout.java:1855)
        at android.view.View.layout(View.java:17638)
        at android.view.ViewGroup.layout(ViewGroup.java:5575)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at android.view.View.layout(View.java:17638)
        at android.view.ViewGroup.layout(ViewGroup.java:5575)
        at androidx.constraintlayout.widget.ConstraintLayout.onLayout(ConstraintLayout.java:1855)
        at android.view.View.layout(View.java:17638)
        at android.view.ViewGroup.layout(ViewGroup.java:5575)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at android.view.View.layout(View.java:17638)
        at android.view.ViewGroup.layout(ViewGroup.java:5575)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1741)
        at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1585)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1494)
        at android.view.View.layout(View.java:17638)
        at android.view.ViewGroup.layout(ViewGroup.java:5575)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at android.view.View.layout(View.java:17638)
        at android.view.ViewGroup.layout(ViewGroup.java:5575)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1741)
        at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1585)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1494)
        at android.view.View.layout(View.java:17638)
        at android.view.ViewGroup.layout(ViewGroup.java:5575)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:323)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:261)
        at com.android.internal.policy.DecorView.onLayout(DecorView.java:727)
2021-05-22 14:38:50.235 5205-5205/com.example.koohestantest1.tak E/AndroidRuntime:     at android.view.View.layout(View.java:17638)
        at android.view.ViewGroup.layout(ViewGroup.java:5575)
        at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2346)
        at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2068)
        at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1254)
        at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6338)
        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:874)
        at android.view.Choreographer.doCallbacks(Choreographer.java:686)
        at android.view.Choreographer.doFrame(Choreographer.java:621)
        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:860)
        at android.os.Handler.handleCallback(Handler.java:751)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:154)
        at android.app.ActivityThread.main(ActivityThread.java:6198)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:891)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:781)
2021-05-22 14:38:50.749 1880-1880/? E/EGL_emulation: tid 1880: eglCreateSyncKHR(1584): error 0x3004 (EGL_BAD_ATTRIBUTE)
2021-05-22 14:42:23.518 2519-19562/? E/WakeLock: GCM_HB_ALARM release without a matched acquire!

这是我的 viewpager 适配器代码：

public class NewsLetterViewPagerAdapter extends PagerAdapter {

    private Context context;
    private List<String> posterList;

    public NewsLetterViewPagerAdapter(Context context, List<String> posterList) {
        this.context = context;
        this.posterList = posterList;
    }

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

    @Override
    public boolean isViewFromObject(@NonNull View view, @NonNull Object object) {
        return view == object;
    }

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

    @NonNull
    @Override
    public Object instantiateItem(@NonNull ViewGroup container, int position) {
        ImageView imageView = new ImageView(context);
        VideoView videoView = new VideoView(context);
        if(posterList.get(position).contains(".jpg") || posterList.get(position).contains(".png")) {
            Glide.with(context).load(posterList.get(position)).into(imageView);
            container.addView(imageView);
            return imageView;
        }else{
            videoView.setVideoURI(Uri.parse(posterList.get(position)));
            videoView.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {
                @Override
                public void onPrepared(MediaPlayer mp) {
                    mp.setLooping(true);
                    videoView.start();
                }
            });
            container.addView(videoView);
            return videoView;
        }
    }
}

这是我在视图寻呼机中加载图像和视频的 onBindViewHolder 代码：

    try {
        JSONArray jsonArray = new JSONArray(newsLetterList.get(position).Jsonsrc);

        posterList.clear();
        for(int i = 0;i < jsonArray.length(); i++){

            posterList.add(jsonArray.getString(i));

        }

        NewsLetterViewPagerAdapter adapter = new NewsLetterViewPagerAdapter(context,posterList);
        holder.slider.setAdapter(adapter);
    } catch (JSONException e) {
        e.printStackTrace();
    }

那么我的错误在哪里？

我应该怎么办？

标签： androidandroid-viewpager