Leggendo la documentazione limitata fornita da Google, ho la sensazione che sia possibile cambiare l'aspetto (disegnabile) di ProgressBar / ProgressDialog semplicemente creando un nuovo stile e assegnandolo alla proprietà style di ProgressBar. Ma non riesco a farlo funzionare correttamente. Ecco cosa ho fatto finora:
Ho creato una forma come questa (mp2.xml)
<?xml version="1.0" encoding="UTF-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="ring"
android:innerRadiusRatio="4"
android:thicknessRatio="4"
android:useLevel="false">
<size android:width="50dip" android:height="50dip" />
<gradient android:type="sweep" android:useLevel="false" android:startColor="#300000ff" android:centerColor="#500000ff" android:endColor="#ff0000ff" />
</shape>
quindi creato un'animazione (mp3.xml) come questa:
<?xml version="1.0" encoding="utf-8"?>
<animation-list xmlns:android="http://schemas.android.com/apk/res/android" android:oneshot="false">
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="0" android:toDegrees="30" android:repeatCount="1" />
</item>
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="30" android:toDegrees="60" android:repeatCount="1" />
</item>
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="60" android:toDegrees="90" android:repeatCount="1" />
</item>
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="90" android:toDegrees="120" android:repeatCount="1" />
</item>
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="120" android:toDegrees="150" android:repeatCount="1" />
</item>
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="150" android:toDegrees="180" android:repeatCount="1" />
</item>
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="180" android:toDegrees="210" android:repeatCount="1" />
</item>
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="210" android:toDegrees="240" android:repeatCount="1" />
</item>
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="240" android:toDegrees="270" android:repeatCount="1" />
</item>
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="270" android:toDegrees="300" android:repeatCount="1" />
</item>
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="300" android:toDegrees="330" android:repeatCount="1" />
</item>
<item android:duration="70">
<rotate xmlns:android="http://schemas.android.com/apk/res/android" android:drawable="@drawable/mp2" android:pivotX="50%" android:pivotY="50%" android:fromDegrees="330" android:toDegrees="360" android:repeatCount="1" />
</item>
</animation-list>
quindi creato uno stile (attrs.xml) come questo:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<style parent="@android:style/Widget.ProgressBar" name="customProgressBar">
<item name="android:progressDrawable">@anim/mp3</item>
</style>
</resources>
e nel mio main.xml ho impostato lo stile in questo modo:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent" android:drawingCacheQuality="high">
<ProgressBar android:id="@+id/ProgressBar01"
android:layout_width="wrap_content"
android:layout_height="wrap_content" style="@style/customProgressBar"/>
</LinearLayout>
Ma mostra ancora lo stesso disegno di prima. Che cosa sto facendo di sbagliato?