windmill 旋转风车

博客：https://blog.csdn.net/yinxing2008/article/details/100260191

旋转风车实现效果

实现方案

对于风车的立柱部分，采用一张固定背景图；
对于风车上面旋转部分，采用一张图，通过安卓属性动画进行旋转。
注意点：因为是采用两张图叠加而形成的效果，所以需要注意调整两张图的相对位置，使之刚好形成风车旋转效果。

主要代码

BaseWindmillView.kt

abstract class BaseWindmillView constructor(context: Context, attrs: AttributeSet? = null) :
 LinearLayout(context, attrs) {
 private fun getRotateAnimation(@IntRange(from = 1, to = 10) speed: Int): RotateAnimation {
     val animateTime = getAnimateTimeFromSpeed(speed)
     val animation = RotateAnimation(
         0f, 360f,
         Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f
     )
     animation.fillAfter = true
     animation.repeatCount = Animation.INFINITE
     animation.duration = animateTime
     animation.interpolator = LinearInterpolator()
     return animation
 }
 private fun getAnimateTimeFromSpeed(speed: Int): Long {
     return (10 * 1000 / speed).toLong()
 }
 fun startRotate(@IntRange(from = 1, to = 10) speed: Int) {
     getToRotateViews().forEach {
         it.clearAnimation()
         it.startAnimation(getRotateAnimation(speed)) }
 }
 abstract fun getToRotateViews(): List<View>
}

DoubleWindmillView.kt
```
class DoubleWindmillView constructor(context: Context, attrs: AttributeSet? = null) :
BaseWindmillView(context, attrs) {
init {
```
 LayoutInflater.from(context).inflate(R.layout.view_double_windmill, this, true)
```
}

override fun getToRotateViews()= listOf(windmillBladeIv,smallWindmillBladeIv)

}

3. view_double_windmill.xml

<?xml version=”1.0” encoding=”utf-8”?>

<ImageView
    android:id="@+id/windmillBladeIv"
    android:layout_width="80dp"
    android:layout_height="80dp"
    android:src="@mipmap/windmill_blade" ></ImageView>
<ImageView
    android:layout_width="24dp"
    android:layout_height="80dp"
    android:layout_marginStart="29dp"
    android:layout_marginTop="32dp"
    android:src="@mipmap/windmill" ></ImageView>
<ImageView
    android:id="@+id/smallWindmillBladeIv"
    android:layout_width="48dp"
    android:layout_height="48dp"
    android:layout_marginStart="50dp"
    android:layout_marginTop="30dp"
    android:src="@mipmap/windmill_blade" ></ImageView>
<ImageView
    android:layout_width="14dp"
    android:layout_height="48dp"
    android:layout_marginStart="67dp"
    android:layout_marginTop="50dp"
    android:src="@mipmap/windmill" ></ImageView>

# lib库集成方法
1. 在工程根目录下build.gradle文件中增加jitpack仓库地址：

allprojects {
repositories {
…
maven { url ‘https://jitpack.io‘ }
}
}

2. 在app工程下build.gradle文件中增加依赖：

dependencies {
implementation ‘com.github.cxyzy11.0.0’
}
```