MainActivity.java

package simpletoasttutorial.tktutorials.com;

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

public class MainActivity extends Activity {
	
	public Button showToast;
	public int duration;
	final Context context = this;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		showToast = (Button) findViewById(R.id.button1);
		duration = Toast.LENGTH_LONG;
		
		showToast.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View arg0) {
				
			Toast.makeText(context, "Hello!", duration).show();				
			
			}
		});
	}

}