Rotating image. Animation list or animated rotate? (Android)

Question

I want to create a rotating progress image, and wonder what's the best way to proceed. I can make it work with an animation list with for example 12 images changing every 100ms. This works fine, but it's quite tedious to create 12 images or for every size and resolution:

<animation-list xmlns:android="http://schemas.android.com/apk/res/android" android:oneshot="false">
<item android:drawable="@drawable/ic_loading_grey_on_black_01" android:duration="100" />
<item android:drawable="@drawable/ic_loading_grey_on_black_02" android:duration="100" />
<item android:drawable="@drawable/ic_loading_grey_on_black_03" android:duration="100" />
<item android:drawable="@drawable/ic_loading_grey_on_black_04" android:duration="100" />
<item android:drawable="@drawable/ic_loading_grey_on_black_05" android:duration="100" />
<item android:drawable="@drawable/ic_loading_grey_on_black_06" android:duration="100" />
<item android:drawable="@drawable/ic_loading_grey_on_black_07" android:duration="100" />
<item android:drawable="@drawable/ic_loading_grey_on_black_08" android:duration="100" />
<item android:drawable="@drawable/ic_loading_grey_on_black_09" android:duration="100" />
<item android:drawable="@drawable/ic_loading_grey_on_black_10" android:duration="100" />
<item android:drawable="@drawable/ic_loading_grey_on_black_11" android:duration="100" />
<item android:drawable="@drawable/ic_loading_grey_on_black_12" android:duration="100" />

I suppose that an easier solution is to use one image per resolution, but rather rotate it for each frame. In the platform resources (android-sdk-windows/platforms...) I found something called animated-rotate in the file drawable/search_spinner.xml, but if I copy the code get a compiler error complaining about android:framesCount and android:frameDuration (Google APIs 2.2 in Eclipse):

<animated-rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:drawable="@drawable/spinner_black_20"
android:pivotX="50%"
android:pivotY="50%"
android:framesCount="12"
android:frameDuration="100" />

I have also tried using a repeating rotate animation (using in the anim resource folder), but I actually prefer the look of the animation list version.

What is the recommended way of solving this problem?

Answer 1

I would try extending ProgressBar.

A google search of "custom progress bar android" gave me:

• http://majaxandroidtips.blogspot.com/2009/06/how-to-create-custom-progress-bar.html
• http://techdroid.kbeanie.com/2010/04/custom-progressbar-for-android.html

Answer 2

You have create a drawable xml file like below:

Code:

<rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:pivotX="50%" android:pivotY="50%" android:fromDegrees="0"
android:toDegrees="360" android:drawable="@drawable/imagefile_to_rotate" />