Android: Custom theme in android application.

Adding demo here to create custom theme in Android application and applying it.

• Custom Theme

This is a very simple demo app to create custom theme in android application.

First create two xml files in values folder...

attrs.xml

themes.xml

In attrs.xml file you will define all the attributes we are going to use as a theme style.

e.g:

<resources>

    <attr name="pageBackground" format="reference" />

</resources>

In themes.xml file we will differentiate this attribute according to our themes.

e.g:

<resources>

    <style name="Theme" parent="android:Theme.Light"></style>

    <style name="Theme.Red">

        <item name="launcherBackground">@style/launcher_background_red</item>

    </style>

    <style name="Theme.Green">

        <item name="launcherBackground">@style/launcher_background_green</item>

    </style>

    <style name="Theme.Blue">

        <item name="launcherBackground">@style/launcher_background_blue</item>

    </style>

</resources>



In styles.xml file we will define actual implementation of different themes and set different property and its value accordingly.

<resources xmlns:android="http://schemas.android.com/apk/res/android">

<!-- Red Theme Start -->
<style name="launcher_background_red">
  <item name="android:background">@drawable/images_1</item>
  </style>
<!-- Red Theme End -->


<!-- Green Theme Start -->
<style name="launcher_background_green">
  <item name="android:background">@drawable/images_2</item>
  </style>
<!-- Green Theme End -->


<!-- Blue Theme Start -->
<style name="launcher_background_blue">
  <item name="android:background">@drawable/images_3</item>
  </style>
<!-- Blue Theme End -->

</resources>




Style:
After adding themes we can set style in our xml layout property like below:::
style="?launcherBackground" // We have added this as attribute in attrs.xml
e.g:

<RelativeLayout style="?launcherBackground">
</RelativeLayout>



Applying Theme:
Now for applying theme in our application we have to set theme in activities like below:::
setTheme(R.style.Theme_Red);

I have added one BaseActivity so that when we will change theme in BaseActivity it will reflect to all the child activities.


We have added theme setting in preference so that when user will relaunch application, application will show in previously selected theme.



You can download demo code from below url:
https://drive.google.com/file/d/0B0mH97AUwQqhclhSdkgtajhGVkU/view?usp=sharing

Android: Supporting multiple language(Localization) in android apps

We can support different language in our Android application using resources file.
I am adding here example for the same.

We are going to support English, Hindi & Marathi language in this demo for this we have to create separate resources folder for all the three language and we will put different resource file in this folder and then we can change application locale using below code :

public static void setLocale(Context context, String locale) {
Locale myLocale = new Locale(locale);
Resources res = context.getResources();
DisplayMetrics dm = res.getDisplayMetrics();
Configuration conf = res.getConfiguration();
conf.locale = myLocale;
res.updateConfiguration(conf, dm);
}

We have to add three different string resource folder (e.g values-hi, values-en, values-ma) with resource file string.xml. Now when we will change application locale, application will automatically choose appropriate resource folder for rendering it on application.

Similarly we can also use different image resources in our application for that we have to create different drawable folder (eg. drawable-hi, drawable-en, drawable-ma) now we can put different image with same name in this drawable resource.

You can download example from below url:
https://drive.google.com/file/d/0B0mH97AUwQqhM0t2RXdMb3QxVHc/edit?usp=sharing