jetpack组合中的RotateAnimation

Question

我有这个RotateAnimation来自于GitHub上的一个项目，我想将同样的旋转应用于我的图像(指南针内箭头)

以下是RotateAnimation的参数：

公共RotateAnimation(浮点fromDegrees，浮点toDegrees，int pivotXType，浮点pivotXValue，int pivotYType，浮点pivotYValue)

这是我的代码：

        angleCompass.value = -angle
        val an = RotateAnimation(
            -currentAngle, -angle,
            Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
            0.5f
        )
        currentAngle = azimuth
        an.duration = 500
        an.repeatCount = 0
        an.fillAfter = true
        binding.imgCompass.startAnimation(an)


        val anim = RotateAnimation(
            -currentAngle + qiblaDir, -azimuth,
            Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF,
            0.5f
        )
        angleNeedle.value = -azimuth
        currentAngle = azimuth
        anim.duration = 500
        anim.repeatCount = 0
        anim.fillAfter = true
        binding.imgQiblaArrow.startAnimation(anim)

如何在作曲中应用相同的动画？

Answer 1

简单的例子，但你可以做到这样；

@Composable
fun AnimatableSurface() {
    val currentAngle = 0f
    val angle = 90f
    val rotateAnim = remember { Animatable(currentAngle) }
    LaunchedEffect(key1 = true){
        rotateAnim.animateTo(angle, tween(2000))
    }
    Surface(
        modifier = Modifier.size(100.dp).rotate(rotateAnim.value),
        color = Color.Red
    ) {}
}