如何从适配器在主活动中设置的接口中获取值

Question

如何从回收器视图适配器获取购物车项目数量到其父活动。

定义接口，在回收器视图适配器中设置项目计数，并在主活动中实现接口

interface OnItemClick {
void onClick (String value);
}

private OnItemClick mCallback;
public VegeHomeAdapter(Context ctx, ArrayList<ModelTopProd> mData, OnItemClick listener) {
this.mData = mData;
this.ctx = ctx;
this.mCallback = listener;
}
int total_items = Integer.parseInt(preferenceHelper.getCARTNO());
total_items+=1;
preferenceHelper.putCARTNO(""+total_items);
mCallback.onClick(""+preferenceHelper.getCARTNO());

public class Home extends AppCompatActivity implements View.OnClickListener, OnItemClick {
public interface OnItemClickListener {
void onItemClick(View view, int position);
}
}

How to set values to text view TextView qtyTV; got from adapter

Answer 1

适配器：

public VegeHomeAdapter(Context ctx, ArrayList<ModelTopProd> mData, OnItemClick listener) {
this.mData = mData;
this.ctx = ctx;
this.mCallback = listener;
interface OnItemClick {
void onClick (String value);
void getTotalItems(int totalItems);
}
}
int total_items = Integer.parseInt(preferenceHelper.getCARTNO());
total_items+=1;
preferenceHelper.putCARTNO(""+total_items);
mCallback.onClick(""+preferenceHelper.getCARTNO());
}

首页：

public class Home extends AppCompatActivity implements View.OnClickListener, OnItemClick {
private int totalItems = 0
@Override 
public onClick(String itemName) { 
//your implementation
}
@Override
public void getTotalItems(int total)  {
totalItems = total;
}

}