test.txt

package com.examples4Android.simple;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class HelloActivity extends Activity implements OnClickListener {
    /** Called when the activity is first created. */
	Button btnInc;
	Button btnDec;
	Button btnShow;
	TextView tvResult;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        System.out.println("Moj test");
        setContentView(R.layout.main);
        String a=new String("aa");
        btnInc = (Button) this.findViewById(R.id.buttonInc);
        btnInc.setOnClickListener(this);
        tvResult = (TextView) findViewById(R.id.textViewResult);
        //btnInc =  findViewByID()
       // btnInc.
     //   btnInc = (Button) 
    }
	@Override
	public void onClick(View v) {
		if (v.getId() == R.id.buttonInc) {
			tvResult.setText("BO");
			//add
		}
		
	}
}


<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
<Button android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/btn_inc" android:id="@+id/buttonInc"></Button>
<Button android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/btn_dec" android:id="@+id/buttonDec"></Button>
<Button android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/btn_show" android:id="@+id/buttonShow"></Button>
<TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:id="@+id/textViewResult" android:text="Rezultat"></TextView>
</LinearLayout>