[android] How to create custom button in Android using XML Styles

Copy-pasted from a recipe written by "Adrián Santalla" on androidcookbook.com: https://www.androidcookbook.com/Recipe.seam?recipeId=3307

1. Create an XML file that represents the button states

Create an xml into drawable called 'button.xml' to name the button states:

<?xml version="1.0" encoding="utf-8"?>

<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:state_enabled="false"
        android:drawable="@drawable/button_disabled" />
    <item
        android:state_pressed="true"
        android:state_enabled="true"
        android:drawable="@drawable/button_pressed" />
    <item
        android:state_focused="true"
        android:state_enabled="true"
        android:drawable="@drawable/button_focused" />
    <item
        android:state_enabled="true"
        android:drawable="@drawable/button_enabled" />
</selector>

2. Create an XML file that represents each button state

Create one xml file for each of the four button states. All of them should be under drawables folder. Let's follow the names set in the button.xml file.

button_enabled.xml:

<?xml version="1.0" encoding="utf-8"?>

<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
    <gradient
        android:startColor="#00CCFF"
        android:centerColor="#0000CC"
        android:endColor="#00CCFF"
        android:angle="90"/>
    <padding android:left="7dp"
        android:top="7dp"
        android:right="7dp"
        android:bottom="7dp" />
    <stroke
        android:width="2dip"
        android:color="#FFFFFF" />
    <corners android:radius= "8dp" />
</shape>

button_focused.xml:

<?xml version="1.0" encoding="utf-8"?>

<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
    <gradient
        android:startColor="#F7D358"
        android:centerColor="#DF7401"
        android:endColor="#F7D358"
        android:angle="90"/>
    <padding android:left="7dp"
        android:top="7dp"
        android:right="7dp"
        android:bottom="7dp" />
    <stroke
        android:width="2dip"
        android:color="#FFFFFF" />
    <corners android:radius= "8dp" />
</shape>

button_pressed.xml:

<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
    <gradient
        android:startColor="#0000CC"
        android:centerColor="#00CCFF"
        android:endColor="#0000CC"
        android:angle="90"/>
    <padding android:left="7dp"
        android:top="7dp"
        android:right="7dp"
        android:bottom="7dp" />
    <stroke
        android:width="2dip"
        android:color="#FFFFFF" />
    <corners android:radius= "8dp" />
</shape>

button_disabled.xml:

<?xml version="1.0" encoding="utf-8"?>

<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
    <gradient
        android:startColor="#F2F2F2"
        android:centerColor="#A4A4A4"
        android:endColor="#F2F2F2"
        android:angle="90"/>
    <padding android:left="7dp"
        android:top="7dp"
        android:right="7dp"
        android:bottom="7dp" />
    <stroke
        android:width="2dip"
        android:color="#FFFFFF" />
    <corners android:radius= "8dp" />
</shape>

3. Create an XML file that represents the button style

Once you have created the files mentioned above, it's time to create your application button style. Now, you need to create a new XML file, called styles.xml (if you don't have it yet) where you can include more custom styles, into de values directory.

This file will contain the new button style of your application. You need to set your new button style features in it. Note that one of those features, the background of your new style, should be set with a reference to the button (button.xml) drawable that was created in the first step. To refer to the new button style we use the name attribute.

The example below show the content of the styles.xml file:

<resources>
    <style name="button" parent="@android:style/Widget.Button">
        <item name="android:gravity">center_vertical|center_horizontal</item>
        <item name="android:textColor">#FFFFFFFF</item>
        <item name="android:shadowColor">#FF000000</item>
        <item name="android:shadowDx">0</item>
        <item name="android:shadowDy">-1</item>
        <item name="android:shadowRadius">0.2</item>
        <item name="android:textSize">16dip</item>
        <item name="android:textStyle">bold</item>
        <item name="android:background">@drawable/button</item>
        <item name="android:focusable">true</item>
        <item name="android:clickable">true</item>
    </style>
</resources>

4. Create an XML with your own custom application theme

Finally, you need to override the default Android button style. For that, you need to create a new XML file, called themes.xml (if you don't have it yet), into the values directory and override the default Android button style.

The example below show the content of the themes.xml:

<resources>
    <style name="YourApplicationTheme" parent="android:style/Theme.NoTitleBar">
        <item name="android:buttonStyle">@style/button</item>
    </style>
</resources>

Hope you guys can have the same luck as I had with this, when I was looking for custom buttons. Enjoy.