Interface graphique

package com.example.carrent;

import android.os.Bundle;
import android.app.Activity;
import android.text.InputType;
import android.view.Menu;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends Activity {
	private TextView hello = null;
     
	protected void onCreate(Bundle savedInstanceState) {
	
		super.onCreate(savedInstanceState);
		EditText editText = new EditText(this);
		hello = new TextView(this);
	    hello.setText(R.string.hello_world);
	 
	    hello.setPadding(15, 105, 21, 105);
	  
	    setContentView(hello);
	   
		
		editText.setHint(R.string.editText);
		editText.setInputType(InputType.TYPE_TEXT_FLAG_MULTI_LINE);
		editText.setLines(5);
	   
		Button button = new Button(this);
		editText.setText(R.string.button);
		
	   
		
	
	}

}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:id="@+id/text"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="25.7dp"
        android:text="@string/hello_world" />

   <EditText 
   android:id="@+id/editText"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content" 
  android:hint="@string/editText"
  android:inputType="textMultiLine"
  android:lines="5" />
  
</RelativeLayout>