Question

I have a problem about setting a TextView from a class which is not a child class of Activity. This class is basically used for handling registration and REST request with 3rd party server.

After getting textfield info from 3rd Party server, it is too late to set TextView in the Main Activity.

• I can’t use SharedPreferences to set this info, because MainActivity has already started.
• I can’t pass this info with Bundle since my java class is not an activity class.

How can I pass this info and set the TextView in the MainActivity? Is there any way to do this?

Answer 1

The proper way of doing this this is to create a listener.

Create an interface :

public interface OperationCompletedListener{
void onOperationCompleted(String resultValue);
}

Then in your class which calls Rest services, create a variable for this listener and a method to set it.

private OperationCompletedListener mListener;

public void setOperationCompletedListener(OperationCompletedListener listener){
mListener=listener;
}

Then when the your rest service completed call like below :

if(mListener!=null){
mListener.onOperationCompleted("your value to be passed");
}

Then in your activity class which contains the TextView, create an object of OperationCompletedListener and set it to the other class using the set method that we created earlier. Then in the onOperationCompleted method, set the text view with your value and you are done.

private OperationCompletedListener mOperationCompletedListener=new OperationCompletedListener() {

    @Override
    public void onOperationCompleted(String resultValue) {
        yourTextView.setText(resultValue);
    }
};

restServiceClassObject.setOperationCompletedListener(mOperationCompletedListener);