Sunday, January 31, 2010

How to populate a Spinner widget from an Array

Lets say we have an Array of colours, defined in a xml file in our res folder in our Eclipse project, like below.

<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="hello">Hello World, droidTest1!</string>
<string name="app_name">droidTest1</string>

<string-array name="colours">
<item>Red</item>
<item>Blue</item>
<item>White</item>
<item>Yellow</item>
<item>Black</item>
<item>Green</item>
<item>Purple</item>
<item>Orange</item>
<item>Grey</item>
</string-array>
</resources>

Spinners are Android's implementation of a dropdown menu, of sorts.
How do we insert these values into a spinner widget?

First, we need to create a layout for our Spinner widget, so it has a user interface.
We could do this is code, but the more accepted method is to define our layouts for Android applications in XML files, located in our res/layout folder in our project.

<Spinner

android:id="@+id/my_colour_spinner"

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:drawSelectorOnTop="true”

/>




Then we create an instance of the Spinner class,

Spinner colourSpinner = (Spinner) findViewById(R.id.my_colour_spinner);



Next we create an ArrayAdapter to wrap our xml array (Array of colours) and we put some pre-defined styles.



ArrayAdapter adapter = ArrayAdapter.createFromResource( this, R.array.colors, android.R.layout.simple_spinner_item); adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);


And we set the ArrayAdapter to our instance of the Spinner class:
colourSpinner.setAdapter(adapter);


And when we run our application:

The closed Spinner Widget



.. When selected shows us out colour options.





Aaah.. Sweet Androidy Success!


Next..

1 comment:

  1. Would love to see this example posted like your SQL one was. Thanks!

    ReplyDelete