Q:

Button Alignment on Android

I am new at the android and I have an issue on button alignment I am trying to align some buttons but I cannot succeed the exact result I want. I will provide you an image on the result I want to succeed 
The xml I have created is this `
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_gravity="center"
    android:background="@drawable/bgmedium" >

    <Button
        android:id="@+id/button1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/button_medium"
        android:text="@string/come_to_us" />

    <Button
        android:id="@+id/button2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/button1"
        android:layout_alignRight="@+id/button1"
        android:layout_below="@+id/button1"
        android:background="@drawable/button_medium"
        android:text="@string/car_exhibition" />

    <Button
        android:id="@+id/button3"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/button2"
        android:layout_alignRight="@+id/button2"
        android:layout_below="@+id/button2"
        android:background="@drawable/button_medium"
        android:text="@string/test_drive" />

    <Button
        android:id="@+id/button4"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/button3"
        android:layout_alignRight="@+id/button3"
        android:layout_below="@+id/button3"
        android:background="@drawable/button_medium"
        android:text="@string/phone_contact" />

    <Button
        android:id="@+id/button5"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/button4"
        android:layout_alignRight="@+id/button4"
        android:layout_below="@+id/button4"
        android:background="@drawable/button_medium"
        android:text="@string/website" />

</RelativeLayout>

`
But the result looks like 

A:

Firstly i suggest that to use LinearLayout for this screen. I will be simpler with linearLayout. You can use gravity property inside button elements to align center your button's texts.
android:gravity="center"

Edit
Result:

layout.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/genel_background"
    android:gravity="center_horizontal"
    android:orientation="vertical"
    android:paddingBottom="20dp"
    android:paddingLeft="20dp"
    android:paddingRight="20dp" >

    <Button
        android:id="@+id/button1"
        style="@style/GirisButton"
        android:text="Button1" >
    </Button>

    <Button
        android:id="@+id/button2"
        style="@style/GirisButton"
        android:text="Button2" >
    </Button>

    <Button
        android:id="@+id/button3"
        style="@style/GirisButton"
        android:text="Button3" >
    </Button>

    <Button
        android:id="@+id/button4"
        style="@style/GirisButton"
        android:text="Button4" >
    </Button>

    <Button
        android:id="@+id/button5"
        style="@style/GirisButton"
        android:text="Button5" >
    </Button>

</LinearLayout>

style element
 <style name="GirisButton">
        <item name="android:layout_marginTop">15dp</item>
        <item name="android:paddingTop">20dp</item>
        <item name="android:paddingBottom">20dp</item>
        <item name="android:layout_width">match_parent</item>
        <item name="android:textSize">18sp</item>
        <item name="android:layout_height">wrap_content</item>
        <item name="android:textColor">@android:color/white</item>
        <item name="android:gravity">center_horizontal|center_vertical</item>
        <item name="android:background">@drawable/giris_button_combined</item>
        <item name="android:textColor">@android:color/white</item>
    </style>

