Android利用android:indeterminateDrawable来实现ProgressBar三种方式

方式1：(效果为补间动画一样)

<ProgressBar
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:indeterminate="true"
android:indeterminateDrawable="@anim/loading" />

<?xml version="1.0" encoding="UTF-8"?>
<animation-list android:oneshot="false"
xmlns:android="http://schemas.android.com/apk/res/android">
<item android:duration="60" android:drawable="@drawable/load_1" />
<item android:duration="60" android:drawable="@drawable/load_3" />
<item android:duration="60" android:drawable="@drawable/load_5" />
<item android:duration="60" android:drawable="@drawable/load_7" />
<item android:duration="60" android:drawable="@drawable/load_9" />
<item android:duration="60" android:drawable="@drawable/load_11" />
<item android:duration="60" android:drawable="@drawable/load_13" />
<item android:duration="60" android:drawable="@drawable/load_15" />
</animation-list>

方式2：（效果为自定义图片让其不断的旋转）

<ProgressBar
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:indeterminate="true"
android:indeterminateDrawable="@drawable/progressbar" />

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >

<item>
<rotate
android:drawable="@drawable/load"
android:fromDegrees="0.0"
android:pivotX="50.0%"
android:pivotY="50.0%"
android:toDegrees="360.0" />
<span style="white-space:pre">	</span>    <!-- 其中360.0值越大，转的圈圈越快 -->
</item>

</layer-list>

方式三：（效果为自定义颜色让其不断的旋转）

<ProgressBar
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:indeterminate="true"
android:indeterminateDrawable="@drawable/progressbar2" />

<pre name="code" class="html"><?xml version="1.0" encoding="utf-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:fromDegrees="0"
android:pivotX="50%"
android:pivotY="50%"
android:toDegrees="360" >
<shape
android:innerRadiusRatio="3"
android:shape="ring"
android:thicknessRatio="8"
android:useLevel="false" >
<gradient
android:centerColor="#FFFFFF"
android:centerY="0.50"
android:endColor="#1E90FF"
android:startColor="#000000"
android:type="sweep"
android:useLevel="false" />
</shap