Question

我正在制作回收视图，该视图水平获取前一活动中检查的视频缩略图。我已经在各地使用Log来查找方法是否正常工作。该方法工作正常，我得到的主要问题是在所有的努力之后，视频缩略图没有填充在所提供的空间中，或者我必须说该区域是空白的。什么都没有。

这是我的自定义布局，它会使回收者视图膨胀：

1。 custom_listview.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#212326"
android:orientation="vertical"
android:layout_marginBottom="3dp">
<ImageView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageView"
    android:scaleType="centerCrop"/></LinearLayout>

现在是editvideo活动，它从前一个片段中获取已检查的文件。

2。 EditVideoActivity.java

public class EditVideoActivity extends AppCompatActivity {

private ImageButton filterButton,cutButton,audioButton;

ArrayList<File> mList = new ArrayList<>();
ListView mListView;

RecyclerView recyclerView;

ViewAdapter viewAdapter;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
    setContentView(R.layout.activity_edit_video);

    getSupportActionBar().setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
    getSupportActionBar().setCustomView(R.layout.edit_header_layout);
    getSupportActionBar().setHomeAsUpIndicator(R.drawable.back);
    getSupportActionBar().setDisplayShowHomeEnabled(true);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);

    filterButton = (ImageButton) findViewById(R.id.filterVideo);
    cutButton = (ImageButton) findViewById(R.id.cutVideo);
    audioButton = (ImageButton) findViewById(R.id.musicalNotes);

    recyclerView = (RecyclerView) findViewById(R.id.videoGallery);
    //checking out for received data
    Bundle extras = getIntent().getExtras();

    String receivedData = extras.getString("sendData");
    Log.e("RECEIVED DATA=====", receivedData);
    String filename;

    for(int i=0;i<receivedData.substring(1,receivedData.length()-1).split(",").length;i++){
        filename = receivedData.split(",")[i];
        File file = new File(filename);
        Log.e("FILENAME===",filename);
        mList.add(file);
    }
    viewAdapter = new ViewAdapter(mList);
    LinearLayoutManager linearLayoutManager = new LinearLayoutManager(EditVideoActivity.this,LinearLayoutManager.HORIZONTAL,false);
    recyclerView.setLayoutManager(linearLayoutManager);
    recyclerView.setAdapter(viewAdapter);


    audioButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent(EditVideoActivity.this, AudioActivity.class);
            startActivity(intent);
        }
    });
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    super.onCreateOptionsMenu(menu);
    getMenuInflater().inflate(R.menu.edit_video, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case android.R.id.home:
            finish();
            return true;

        case R.id.moveNext:
            Intent intent = new Intent(EditVideoActivity.this,PreviewActivity.class);
            startActivity(intent);
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

@Override
public void onBackPressed() {
    moveTaskToBack(false);
}

ViewAdapter类在这里：

第3。 ViewAdapter类

 class ViewAdapter extends RecyclerView.Adapter<ViewAdapter.ViewHolder> {


    private View rootView;
    ArrayList<File> files;

    private Bitmap bitmap;

    public ViewAdapter(ArrayList<File>items) {
        files = items;
        Log.e("ADAPTER","CONSTRUCTOR CALLED");
        //inflating the layout
    }
    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            Log.e("ADAPTER","VIEW HOLDER CREATED");
       rootView = LayoutInflater.from(parent.getContext()).inflate(R.layout.custom_listview,parent,false);
        return new ViewHolder(rootView);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        Log.e("ADAPTER",files.get(position).toString());

        if (files != null) {

            bitmap = ThumbnailUtils.createVideoThumbnail(files.get(position).toString(),1);
        }

        holder.mImageView.setImageBitmap(bitmap);
       // holder.mImageView.setId(position);
    }

    @Override
    public int getItemCount() {
        return files.size();
    }


    class ViewHolder extends RecyclerView.ViewHolder {
        public ImageView mImageView;
        public TextView mTextView;
        public ViewHolder(View view){
            super(view);
            mImageView = (ImageView) view.findViewById(R.id.imageView);
        }
    }
} }

问题是onBindViewHolder部分 if ，因为由于我正在使用的位图对象而没有加载文件。任何帮助都将受到高度赞赏

**编辑：**

在onBindViewHolder中我测试了使用log in if方法。我得到的是NullPointerException。这意味着它没有制作任何缩略图。

在这里：

if(files != null){
   bitmap = ThumbnailUtils.createThumbnail(files.get(position).toString(),1);
Log.e("FILES======",bitmap.toString());
}

在位图定义下方使用Log.e时，Logcat出错

08-08 16:34:12.548 22000-22000/in.pinelane.myhovi E/AndroidRuntime: FATAL EXCEPTION: main
                                                                Process: in.pinelane.myhovi, PID: 22000
                                                                java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference
                                                                    at in.pinelane.myhovi.EditVideoActivity$ViewAdapter.onBindViewHolder(EditVideoActivity.java:149)
                                                                    at in.pinelane.myhovi.EditVideoActivity$ViewAdapter.onBindViewHolder(EditVideoActivity.java:118)

RecyclerView

0 个答案: