import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends Activity {
    Button new_claim_button;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        new_claim_button = (Button) this.findViewById(R.id.button1);
        new_claim_button.setOnClickListener(new OnClickListener() {

            }
            });
    }
}

new_claim_button.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        //implementation
    }
});