Question

I am new to Android development and I want to learn how to style a button element. i am familiar with styling in HTML (CSS and HTML styling). For example How can I translate and implement this css styling into Android (I assume XML styling):

.buttonClass{
     background-color: #fff;
     color: #000;
     border-radius: 10px;
     opacity: 0.5
 ...
}

I have this button element code the Graphical Layout created for me on Eclipse:

<Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Camera" />

Answer 1

You can do this like this:
for background color:

android:background="#ARGB" //alpha, red, green, blue or a drawable

if you want to have a rounded button:

android:background="@drawable/myBtnWithColor"

The “myBtnWithColor” XML file:

<?xml version="1.0" encoding="UTF-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
     android:shape="rectangle">

     <gradient android:startColor="#yourColor" android:endColor="#yourColor"
     <corners android:bottomRightRadius="7dp" android:bottomLeftRadius="7dp"
     android:topLeftRadius="7dp" android:topRightRadius="7dp"/>
</shape> 

You can set the opacity of the Button in your Backgroundcolor. As mentioned you can set alpha values in your colors.