Is it possible to use style sheet in an application?

Android% "do not use" / "do not support" StyleSheet you can change is Views textColor , etc by typeface XML.

For example:

<TextView
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:textColor="#00FF00"
    android:typeface="monospace"
    android:text="@string/hello" />

Style

Another way to change that will look similar to CSS is to use the View attribute, like this:

<TextView
    style="@style/CodeFont"
    android:text="@string/hello" />

This style="" can be applied to multiple Views.

Inheritance

You can also use inheritance just like in CSS with the @style/CodeFont attribute:

<style name="GreenText" parent="@android:style/TextAppearance">
    <item name="android:textColor">#00FF00</item>
</style>

In the parent tag you can use the style attribute to inherit other styles from other name tags. It would look something like:

<style name="CodeFont">
...
</style>

This will inherit style and apply something else

<style name="CodeFont.Red">
...
</style>

This will inherit CodeFont and CodeFont and apply something else

<style name="CodeFont.Red">
...
</style>

But you still will not get very advanced effects

Using WebView

There is a way to use CodeFont.Red to create applications and thus use CSS. But your applications will be almost entirely in HTML.

You need to create a WebView :

<?xml version="1.0" encoding="utf-8"?>
<WebView  xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/webview"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
/>

And you need to enable JavaScript:

WebView myWebView = (WebView) findViewById(R.id.webview);
WebSettings webSettings = myWebView.getSettings();
webSettings.setJavaScriptEnabled(true);

To load a resource file use the url path as WebView , example:

myWebView.loadUrl("file:///android_asset/html/index.html");

To load the stylesheet, use something like in your html:

<link rel="stylesheet" type="text/css" href="file:///android_asset/css/main.css">

To load backgrounds in CSS, do something like:

body {
   background: url(file:///android_asset/images/bg.jpg);
}

To understand how to use the resources read: link

Material Design

  

Note: Requires Android 5.0 (API level 21)

Android now has "Material Design" that can help you, read Creating Apps with Material Design

You can use it by calling:

• file:///android_asset/... (dark version)
• @android:style/Theme.Material (light version)
• @android:style/Theme.Material.Light

Using inheritance to call the theme:

  <style name="AppTheme" parent="android:Theme.Material">
    <!-- Cores do tema -->

    <!--   Cores do appbar -->
    <item name="android:colorPrimary">@color/primary</item>

    <!--   variação "dark" para a barra de estado e o contexto das "barras de ferramentas" -->
    <item name="android:colorPrimaryDark">@color/primary_dark</item>

    <!--   Tema UI dos controles (tipo checkboxes e campos de texto) -->
    <item name="android:colorAccent">@color/accent</item>
  </style>

Where to start: link

Can not use CSS in View's pure Android. If you use WebView you can of course.

But you can create Styles which can be associated with them by the android:style attribute, which would be similar to a css class / selector. But this styling follows the android pattern, with the attributes you already use.

An example would be:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <style name="CodeFont" parent="@android:style/TextAppearance.Medium">
        <item name="android:layout_width">fill_parent</item>
        <item name="android:layout_height">wrap_content</item>
        <item name="android:textColor">#00FF00</item>
        <item name="android:typeface">monospace</item>
    </style>
</resources>

To use:

<EditText
    android:id="@+id/edittext"
    android:style="@style/CodeFont" <!-- "import" do estilo criado -->
    android:layout_alignLeft="@+id/button"
    android:layout_below="@+id/textView1"
    android:layout_marginTop="61dp"
    android:ems="10"
    android:text="@string/enter_text"
    android:inputType="text" />

Some references:

• link
• link