如何从另一个类（使用 ViewHolder）调用 MainActivity 中的方法？

Question

I have an activity. I have to run a method in the other class in this activity. I'm using ViewHolder in the other class. I am told that I need to add a "super ()" method when I call the class directly. But I can't do this. Because I've already added. Although I call the method differently, I am told that I need to set the method as static. But in this way, Textview and buttons do not work in this class. I don't know what to do and I couldn't find a solution. I would be glad if you could help.

My Activity;

public class MainActivity extends AppCompatActivity implements RewardedVideoAdListener {

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

        //First Step - DOES NOT WORK !!!!
        MyClass myClass = new MyClass();
        myClass.myMethod();
        //Doesn't work. Because i want to add super() method to MyClass. But i was added earlier. I can't use again.


        //Secondly Step - DOES NOT WORK !!!!
        MyClass .myMethod();
        //Doesn't work. Because i want to add public void static to method. If i add static my method, i can't use buttons or textviews.
     }
}

MyClass;

public class MyClass extends RecyclerView.ViewHolder {

    //Example
    public TextView mytextview;
    private boolean myboolean = false;

    public MyClass (View itemView) {
        super(itemView);

        mytextview= (TextView)itemView.findViewById(R.id.mytextview);
    }

    public void myMethod(){

    myboolean = false;

    if (!myboolean){

     myboolean = true;
     mytextview.setVisibility(View.VISIBLE);
    } 

    else {

     myboolean = false;
     mytextview.setVisibility(View.INVISIBLE);
    }

    }

  //If i static method, doesn't work other view. example:textview.setvisibility or myboolean=true etc.... I can't use private static Textview or others...
  public static void myMethod(){

        myboolean = false;

     if (!myboolean){

     myboolean = true;
     mytextview.setVisibility(View.VISIBLE);
    } 

    else {

     myboolean = false;
     mytextview.setVisibility(View.INVISIBLE);
       }
    }
}

Answer 1

Do this in your MainActity.

public class MainActivity extends AppCompatActivity implements RewardedVideoAdListener 
 {

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

 TextView yourActivityMainTextView=findViewById(R.id.your_txt_view_id) //from activity 
  main xml

    MyClass myClass = new MyClass(yourActivityMainTextView);
    myClass.myMethod();


 }
}

Answer 2

Here, I am feeling that you are using Recylerview's ViewHolder in different way which is not recommended. My thoughts are, you are using RecylerView.ViewHolder to show the list with the use of RecyclerView.

If yes, then you should use a class that extends RecyclerView.Adapter and create a class for ViewHolder. You can pass your method inside Adapter which will be very easy for you to access through your Activity.

public class AnyAdapter extends RecyclerView.Adapter<YourObjectType> {
     public TextView mytextview;
     private boolean myboolean = false;

     public MyClass (View itemView) {
        super(itemView);
        mytextview= (TextView)itemView.findViewById(R.id.mytextview);
     } 

    static class ViewHolder {
        ImageView downloadImageButton;
        TextView catlogTitle;
        ImageView icon;
        int position;
    }

    public View getView(final int position, View convertView, ViewGroup parent) {
        ...
    } // close getView
}

Create object of Adapter in Activity like this:

AnyAdapter adapter = new AnyAdapter();

You can able to access your method like this. Hope it will work for you.

Happy Coding..!

Answer 3

You just need to add adapter in your project. Below link will help you https://abhiandroid.com/ui/adapter