java - 销毁 ViewPager

Question

我正在尝试克隆 TikTok 应用。对于主屏幕，我制作了一个 VerticalViewPager(自定义 View 分页器)，其中包含“点赞”按钮、标题和评论。我正在从 Firebase 检索视频。 TikTok 模型有视频 URL、标题名称和点赞数。问题是当我尝试转到下一个视频时，上一个视频仍在播放背景。我试图销毁该 fragment ，但似乎不起作用。

这是我的HomeActivity.java

public class HomeActivity extends AppCompatActivity {

    private VerticalPageViewer viewPager;
    private ViewPageAdapter viewPageAdapter;
    private List<TikTokModel> tikTokModels;

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

        viewPager = findViewById(R.id.viewPager);
        tikTokModels = new ArrayList<>();
        FirebaseFirestore.getInstance().collection("TikTok")
                .get()
                .addOnCompleteListener(new OnCompleteListener<QuerySnapshot>() {
                    @Override
                    public void onComplete(@NonNull Task<QuerySnapshot> task) {
                        tikTokModels.clear();
                        if(task.isSuccessful()){
                            for(QueryDocumentSnapshot queryDocumentSnapshot : task.getResult()){
                                tikTokModels.add(queryDocumentSnapshot.toObject(TikTokModel.class));
                            }
                            Log.d("TEST", "onComplete: "+tikTokModels.get(0).getTitle());

                            viewPageAdapter = new ViewPageAdapter(getSupportFragmentManager(),tikTokModels);
                            viewPager.setAdapter(viewPageAdapter);
                        }
                    }
                })
                .addOnFailureListener(new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception e) {

                    }
                });
    }
}

还有ViewPageAdapter.java

class ViewPageAdapter extends PagerAdapter {

    private List<TikTokModel> tikTokModels;
    private Context context;
    private ImageButton playButton;
    private VideoView videoView;

    ViewPageAdapter(List<TikTokModel> tikTokModels, Context context) {
        this.tikTokModels= tikTokModels;
        this.context = context;
    }

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

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

    @NonNull
    @Override
    public Object instantiateItem(@NonNull ViewGroup container, int position) {
        View v = LayoutInflater.from(context).inflate(R.layout.tiktok_frame, container, false);

        TextView title = v.findViewById(R.id.title);
        videoView = v.findViewById(R.id.videoView);
        LikeButton likeButton = v.findViewById(R.id.like);
        playButton = v.findViewById(R.id.playButton);

        playButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (videoView.isPlaying()) {
                    videoView.pause();
                    playButton.setVisibility(View.VISIBLE);
                } else {
                    videoView.resume();
                    playButton.setVisibility(View.INVISIBLE);
                }
            }
        });

        Uri uri = Uri.parse(tikTokModels.get(position).getUrl());
        title.setText(tikTokModels.get(position).getTitle());
        videoView.setVideoURI(uri);
        videoView.requestFocus();
        videoView.start();
        playButton.setVisibility(View.INVISIBLE);

        container.addView(v,0);
        return v;
    }

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

Answer 1

在您的 TikTokFragment 中，您可以考虑重写以下生命周期方法来暂停/恢复您的视频。

@Override
public void setUserVisibleHint(boolean isVisibleToUser) {
    super.setUserVisibleHint(isVisibleToUser);
    if (isVisibleToUser) {
        if (videoView != null) videoView.pause();
    } else {
        if (videoView != null) videoView.resume();
    }
}