How can I use findViewById within a static method?-CodePudding

I would like to use findViewById in my method "setTotalSum" which is called from another class. How can I use it although it's a static method?

public SecondaryDisplay(Context outerContext, Display display) {
    super(outerContext, display);
}

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

public static void setTotalSum (String invoiceTotalSum){
    TextView totalPrice = (TextView)findViewById(R.id.invoicePrice);
    totalPrice.setText(invoiceTotalSum);
}

CodePudding user response：

findViewById() is an instance method of the View which is the parent of Activity and Fragment. You can't use instance methods in static methods.

Either you should pass the view as the param (what I would not recommend) or find another way around to do it without static methods.

public static void setTotalSum (View view, String invoiceTotalSum){
    TextView totalPrice = (TextView) view.findViewById(R.id.invoicePrice);
    totalPrice.setText(invoiceTotalSum);
}

CodePudding user response：

If two class is in same package then directly call another class static method by class name.

A.java

public class A {
    public static some() {
      ...
    }
}

B.java

public class B {
    public static someExtra() {
      A.some(); //call by class name
      
      A a = new A();
      a.some(); //call by refrence also
    }
}

but if some is not static method then create object of A class and then call the method.

Ex:-

public class B {
    public static someExtra() {
        A a = new A();
        a.some();
    }
}

Note:- If two class is in diffrent package then must include import.