android - 房间持久性库(依赖性问题)，MVVM设计模式

Iam遵循MVVM教程以及添加Room dependency时

1- 我在编译时遇到此错误:

Note: Failed to read get kotlin metadata for [Ljava.lang.Object;@54d771f9

Note: Failed to read get kotlin metadata for [Ljava.lang.Object;@4c00a268

Note: Failed to read get kotlin metadata for [Ljava.lang.Object;@42104314

Note: Failed to read get kotlin metadata for [Ljava.lang.Object;@203b72ad

2- 也这样:(已解决)

error: cannot find symbol class of

在MainActivity中添加此代码时:

public class MainActivity extends AppCompatActivity {
private NoteViewModel noteViewModel;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    //error is here in the ViewModelProviders.of
    noteViewModel = new ViewModelProviders.of(this).get(NoteViewModel.class);
    noteViewModel.getAllNotes().observe(this, notes -> {
        //update RecyclerView
        Toast.makeText(MainActivity.this, "onChanged", Toast.LENGTH_SHORT).show();
    });
 }
}

build.gradle(项目):

repositories {
 google()
 jcenter()
 maven { url "https://kotlin.bintray.com/kotlinx/" }
}



allprojects {
 repositories {
  google()
 jcenter()
 maven { url "https://kotlin.bintray.com/kotlinx/" }
 }
}

build.gradle(app):

room_version = "2.1.0-alpha06"

implementation "androidx.room:room-runtime:$room_version"
annotationProcessor "androidx.room:room-compiler:$room_version"

最佳答案

删除new，
这将工作:
noteViewModel = ViewModelProviders.of(this).get(NoteViewModel.class);