Android Application Development Cookbook: 93 Recipes for Building Winning Apps

Recipe 3.7 Displaying a List of Images

Android Versions

Level 1 and above

Permissions

None

Source Code to Download from Wrox.com

Gallery.zip

So far, all the recipes covered involve displaying mainly text and occasionally images. If you want to display a series of images to the user, you can make use of the Gallery. The Gallery is a view that shows items (such as images) in a center-locked, horizontal scrolling list. This recipe shows you how to use it.

Solution

For this recipe, assume you have some images stored in the res/drawable-mdpi folder of your project (see Figure 3-15).

Create an XML file named attrs.xml and store it in the res/values folder (see Figure 3-16).

Figure 3-15

Figure 3-16

The content of the attrs.xml looks like this:

<resources>
    <declare-styleable name="MyGallery">
        <attr name="android:galleryItemBackground" />
    </declare-styleable>   
</resources>

To use the Gallery, add the <Gallery> element in your UI, such as the activity_main.xml file:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical"> <Gallery android:id="@+id/gallery1" android:layout_width="fill_parent" android:layout_height="wrap_content" /> <ImageView android:id="@+id/image1" ...