PieChartView.kt
package com.snowdeer.animation.sample.component
import android.content.Context
import android.graphics.*
import android.util.AttributeSet
import android.view.View
import kotlin.math.cos
import kotlin.math.sin
data class ValueItem(var name: String, var value: Float, var color: Int)
class PieChartView(context: Context?, attrs: AttributeSet?) : View(context, attrs) {
private val WIDTH = 800
private val HEIGHT = 800
private var list = ArrayList<ValueItem>()
fun setValueList(list: ArrayList<ValueItem>) {
this.list = list
invalidate()
}
override fun onDraw(canvas: Canvas?) {
drawSlice(canvas)
drawText(canvas)
}
private fun drawSlice(canvas: Canvas?) {
val total = getTotalSize()
val dAngle = 360.0F / total
val centerX = measuredWidth / 2
val centerY = measuredHeight / 2
val left = centerX - WIDTH / 2
val top = centerY - HEIGHT / 2
val right = centerX + WIDTH / 2
val bottom = centerY + HEIGHT / 2
val rectF = RectF(left.toFloat(), top.toFloat(), right.toFloat(), bottom.toFloat())
var fromAngle = 0.0F
for (item in list) {
val paint = Paint()
paint.color = item.color
val sweepAngle = item.value * dAngle
val drawArc = canvas?.drawArc(rectF, fromAngle, sweepAngle, true, paint)
fromAngle += sweepAngle
}
}
private fun drawText(canvas: Canvas?) {
val total = getTotalSize()
val dAngle = 360.0F / total
val centerX = measuredWidth / 2
val centerY = measuredHeight / 2
val left = centerX - WIDTH / 2
val top = centerY - HEIGHT / 2
val right = centerX + WIDTH / 2
val bottom = centerY + HEIGHT / 2
val rectF = RectF(left.toFloat(), top.toFloat(), right.toFloat(), bottom.toFloat())
val rect = Rect(left, top, right, bottom)
var fromAngle = 0.0F
for (item in list) {
val text = item.name
val sweepAngle = item.value * dAngle
val angle = (fromAngle + (sweepAngle / 2.0F)) * 0.0174532925F
val paint = Paint()
paint.color = Color.BLACK
paint.textSize = 40F
paint.textAlign = Paint.Align.CENTER
canvas?.save()
paint.getTextBounds(text, 0, text.length, rect)
var x = rectF.centerX() + cos(angle) * (rectF.width() / 4 + rect.width() / 2)
val y = rectF.centerY() + sin(angle) * (rectF.height() / 4 + rect.width() / 2)
x -= rect.width() / 2
canvas?.rotate(
fromAngle + (sweepAngle / 2), (x + rect.exactCenterX()),
(y + rect.exactCenterY())
)
canvas?.drawText(text, x, y, paint)
canvas?.restore()
fromAngle += sweepAngle
}
}
private fun getTotalSize(): Float {
var sum = 0.0F
for (item in list) {
sum += item.value
}
return sum
}
}
RouletteFragment.kt
package com.snowdeer.animation.sample.fragment
import android.animation.ObjectAnimator
import android.graphics.Color
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.core.animation.doOnEnd
import androidx.fragment.app.Fragment
import com.snowdeer.animation.sample.R
import com.snowdeer.animation.sample.component.ValueItem
import kotlinx.android.synthetic.main.fragment_roulette.*
import android.view.animation.DecelerateInterpolator
import kotlinx.android.synthetic.main.fragment_roulette.view.*
import java.util.*
import kotlin.collections.ArrayList
class RouletteFragment : Fragment() {
private var degree = 0
private var isAnimating = false
private val candidateList = arrayListOf(
ValueItem("snowdeer", 1.0F, Color.parseColor("#FFDECF3F")),
ValueItem("yang", 1.0F, Color.parseColor("#FFF17CB0")),
ValueItem("down", 1.0F, Color.parseColor("#FF4D4D4D")),
ValueItem("ran", 1.0F, Color.parseColor("#FFB2912F")),
ValueItem("song", 1.0F, Color.parseColor("#FF00B200")),
ValueItem("john", 1.0F, Color.parseColor("#FFFD4425"))
)
private var itemCount = 3
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val view = inflater.inflate(R.layout.fragment_roulette, container, false)
view.piechart_view.setValueList(getList(itemCount))
view.add_button.setOnClickListener {
itemCount++
if (itemCount >= candidateList.size) {
itemCount = candidateList.size
}
view.piechart_view.setValueList(getList(itemCount))
}
view.remove_button.setOnClickListener {
itemCount--
if (itemCount <= 1) {
itemCount = 1
}
view.piechart_view.setValueList(getList(itemCount))
}
view.rotate_button.setOnClickListener {
rotate()
}
return view
}
private fun getList(count: Int): ArrayList<ValueItem> {
val list = ArrayList<ValueItem>()
for (i in 0 until count) {
list.add(this.candidateList[i])
}
return list
}
private fun rotate() {
val random= Random()
if (!isAnimating) {
isAnimating = true
val targetDegree = degree + random.nextInt(360) * (random.nextInt(7) + 7)
val rotateAnimator = ObjectAnimator.ofFloat(piechart_view,
"rotation", degree.toFloat(), targetDegree.toFloat())
rotateAnimator.interpolator = DecelerateInterpolator()
rotateAnimator.duration = 3000
rotateAnimator.doOnEnd {
degree = targetDegree
isAnimating = false
}
rotateAnimator.start()
}
}
}
