Android绘制双折线图的方法
时间：2022-10-26 09:56:47 | 栏目：Android代码 | 点击：次
本文实例为大家分享了Android绘制双折线图的具体代码，供大家参考，具体内容如下
自定义View实现双折线图，可点击，点击后带标签描述，暂未实现拖动的功能，实现效果如下：
代码如下：
首先，自定义布局属性：
<declare-styleable name="LineChart"> <!--type2.LineChart(双折线图)--> <attr name="maxYValue" format="integer" /> <attr name="yLabelCount" format="integer" /> <attr name="xLabelTextSize" format="dimension" /> <attr name="xLabelTextColor" format="color" /> <attr name="xLabelTextMarginTop" format="dimension" /> <attr name="showYLabelText" format="boolean" /> <attr name="yLabelTextSize" format="dimension" /> <attr name="yLabelTextColor" format="color" /> <attr name="yLabelTextMarginLeft" format="dimension" /> <attr name="axisWidth" format="dimension" /> <attr name="axisColor" format="color" /> <attr name="showScale" format="boolean" /> <attr name="scaleLength" format="dimension" /> <attr name="showGrid" format="boolean" /> <attr name="gridWidth" format="dimension" /> <attr name="gridDashInterval" format="dimension" /> <attr name="gridDashLength" format="dimension" /> <attr name="gridColor" format="color" /> <attr name="lineWidth" format="dimension" /> <attr name="lineColor1" format="color" /> <attr name="lineColor2" format="color" /> <attr name="labelWidth" format="dimension" /> <attr name="labelHeight" format="dimension" /> <attr name="labelBackgroundColor" format="color" /> <attr name="labelRadius" format="dimension" /> <attr name="labelTextSize" format="dimension" /> <attr name="labelTextColor" format="color" /> <attr name="labelArrowWidth" format="dimension" /> <attr name="labelArrowHeight" format="dimension" /> <attr name="labelArrowOffset" format="dimension" /> <attr name="labelArrowMargin" format="dimension" /> <attr name="clickAble" format="boolean" /> <attr name="leftMargin" format="dimension" /> <attr name="topMargin" format="dimension" /> <attr name="rightMargin" format="dimension" /> <attr name="bottomMargin" format="dimension" /> </declare-styleable>
LineChart的实现如下：
class LineChart @JvmOverloads constructor(
context: Context, attrs: AttributeSet? = null, @AttrRes defStyleAttr: Int = 0
) : View(context, attrs, defStyleAttr) {
companion object {
private val DEFAULT_MAX_YVALUE = 5000
private val DEFAULT_YLABEL_COUNT = 4
private val DEFAULT_XLABEL_TEXT_SIZE = SizeUtil.sp2px(10f)
private val DEFAULT_XLABEL_TEXT_COLOR = Color.parseColor("#999999")
private val DEFAULT_XLABEL_TEXT_MARGIN_TOP = SizeUtil.dp2px(10f)
private val DEFAULT_SHOW_YLABEL_TEXT = false
private val DEFAULT_YLABEL_TEXT_SIZE = SizeUtil.sp2px(11f)
private val DEFAULT_YLABEL_TEXT_COLOR = Color.BLACK
private val DEFAULT_YLABEL_TEXT_MARGIN_LEFT = SizeUtil.dp2px(15f)
private val DEFAULT_AXIS_WIDTH = SizeUtil.dp2px(0.5f)
private val DEFAULT_AXIS_COLOR = Color.parseColor("#F1F1F1")
private val DEFAULT_SHOW_SCALE = true
private val DEFAULT_SCALE_LENGTH = SizeUtil.dp2px(4f)
private val DEFAULT_SHOW_GRID = true
private val DEFAULT_GRID_WIDTH = SizeUtil.dp2px(0.5f)
private val DEFAULT_GRID_DASH_INTERVAL = SizeUtil.dp2px(1f)
private val DEFAULT_GRID_DASH_LENGTH = SizeUtil.dp2px(2f)
private val DEFAULT_GRID_COLOR = Color.parseColor("#F1F1F1")
private val DEFAULT_LINE_WIDTH = SizeUtil.dp2px(1.5f)
private val DEFAULT_LINE_COLOR1 = Color.parseColor("#60BF56")
private val DEFAULT_LINE_COLOR2 = Color.parseColor("#108EE9")
private val DEFAULT_LABEL_WIDTH = SizeUtil.dp2px(135f)
private val DEFAULT_LABEL_HEIGHT = SizeUtil.dp2px(78f)
private val DEFAULT_LABEL_BACKGROUND_COLOR = Color.WHITE
private val DEFAULT_LABEL_RADIUS = SizeUtil.dp2px(3f)
private val DEFAULT_LABEL_TEXT_SIZE = SizeUtil.sp2px(11f)
private val DEFAULT_LABEL_TEXT_COLOR = Color.parseColor("#333333")
private val DEFAULT_LABEL_ARROW_WIDTH = SizeUtil.dp2px(8f)
private val DEFAULT_LABEL_ARROW_HEIGHT = SizeUtil.dp2px(2f)
private val DEFAULT_LABEL_ARROW_OFFSET = SizeUtil.dp2px(31f)
private val DEFAULT_LABEL_ARROW_MARGIN = SizeUtil.dp2px(14.5f)
private val DEFAULT_CLICKABLE = true
private val DEFAULT_LEFT_MARGIN = SizeUtil.dp2px(15f)
private val DEFAULT_TOP_MARGIN = SizeUtil.dp2px(118f)
private val DEFAULT_RIGHT_MARGIN = SizeUtil.dp2px(15f)
private val DEFAULT_BOTTOM_MARGIN = SizeUtil.dp2px(70f)
}
//Y轴最大值
var maxYValue: Int = DEFAULT_MAX_YVALUE
//Y轴上的刻度值个数
var yLabelCount: Int = DEFAULT_YLABEL_COUNT
//X轴刻度值文本字体大小
var xLabelTextSize: Float = DEFAULT_XLABEL_TEXT_SIZE
//X轴刻度值文本字体颜色
var xLabelTextColor: Int = DEFAULT_XLABEL_TEXT_COLOR
//X轴刻度值文本到X轴的上边距
var xLabelTextMarginTop: Float = DEFAULT_XLABEL_TEXT_MARGIN_TOP
//是否显示Y轴刻度值文本
var showYLabelText: Boolean = DEFAULT_SHOW_YLABEL_TEXT
//Y轴刻度值文本字体大小
var yLabelTextSize: Float = DEFAULT_YLABEL_TEXT_SIZE
//Y轴刻度值文本字体颜色
var yLabelTextColor: Int = DEFAULT_YLABEL_TEXT_COLOR
//Y轴刻度值文本到屏幕左侧的左边距
var yLabelTextMarginLeft: Float = DEFAULT_YLABEL_TEXT_MARGIN_LEFT
//X轴宽度
var axisWidth: Float = DEFAULT_AXIS_WIDTH
//X轴颜色
var axisColor: Int = DEFAULT_AXIS_COLOR
//是否显示轴线上的小刻度线，默认显示
var showScale: Boolean = DEFAULT_SHOW_SCALE
//X轴上的小刻度线长度
var scaleLength: Float = DEFAULT_SCALE_LENGTH
//是否显示网格，默认显示
var showGrid: Boolean = DEFAULT_SHOW_GRID
//网格线宽度
var gridWidth: Float = DEFAULT_GRID_WIDTH
//网格线组成虚线的线段之间的间隔
var gridDashInterval: Float = DEFAULT_GRID_DASH_INTERVAL
//网格线组成虚线的线段长度
var gridDashLength: Float = DEFAULT_GRID_DASH_LENGTH
//网格线颜色
var gridColor: Int = DEFAULT_GRID_COLOR
//折线宽度
var lineWidth: Float = DEFAULT_LINE_WIDTH
//折线一颜色
var lineColor1: Int = DEFAULT_LINE_COLOR1
//折线二颜色
var lineColor2: Int = DEFAULT_LINE_COLOR2
//标签的矩形宽度
var labelWidth: Float = DEFAULT_LABEL_WIDTH
//标签的矩形高度
var labelHeight: Float = DEFAULT_LABEL_HEIGHT
//标签背景颜色
var labelBackgroundColor = DEFAULT_LABEL_BACKGROUND_COLOR
//标签的矩形圆角
var labelRadius: Float = DEFAULT_LABEL_RADIUS
//标签内文本字体大小
var labelTextSize: Float = DEFAULT_LABEL_TEXT_SIZE
//标签内文本字体颜色
var labelTextColor: Int = DEFAULT_LABEL_TEXT_COLOR
//标签的箭头宽度
var labelArrowWidth: Float = DEFAULT_LABEL_ARROW_WIDTH
//标签的箭头高度
var labelArrowHeight: Float = DEFAULT_LABEL_ARROW_HEIGHT
//标签的箭头到标签左侧或右侧的偏移量
var labelArrowOffset: Float = DEFAULT_LABEL_ARROW_OFFSET
//标签的箭头到坐标轴最上方的下边距
var labelArrowMargin: Float = DEFAULT_LABEL_ARROW_MARGIN
//是否可点击
var clickAble: Boolean = DEFAULT_CLICKABLE
//坐标轴到View左侧的边距，多出来的空间可以用来绘制Y轴刻度文本
var leftMargin: Float = DEFAULT_LEFT_MARGIN
//坐标轴到View顶部的边距，多出来的空间可以用来绘制标签信息
var topMargin: Float = DEFAULT_TOP_MARGIN
//坐标轴到View右侧的边距
var rightMargin: Float = DEFAULT_RIGHT_MARGIN
//坐标轴到View底部的边距，多出来的空间可以用来绘制X轴刻度文本
var bottomMargin: Float = DEFAULT_BOTTOM_MARGIN
private var mCurrentDrawIndex = 0
private lateinit var mAxisPaint: Paint //绘制轴线和轴线上的小刻度线
private lateinit var mGridPaint: Paint //绘制网格线
private lateinit var mLinePaint: Paint //绘制折线
private lateinit var mLabelPaint: Paint //绘制最上方标签
private lateinit var mLabelBgPaint: Paint //绘制标签背景，带阴影效果
private lateinit var mTextPaint: Paint //绘制文本
private lateinit var mLabelRectF: RectF //最上方的标签对应的矩形
private var mWidth: Int = 0
private var mHeight: Int = 0
private var mXPoint: Float = 0f //原点的X坐标
private var mYPoint: Float = 0f //原点的Y坐标
private var mXScale: Float = 0f //X轴刻度长度
private var mYScale: Float = 0f //Y轴刻度长度
private var mXLength: Float = 0f //X轴长度
private var mYLength: Float = 0f //Y轴长度
private var mClickIndex: Int = 0 //点击时的下标
private var mDataList1: MutableList<Float> = mutableListOf() //折线一(交易收益)对应数据
private var mDataList2: MutableList<Float> = mutableListOf() //折线二(返现收益)对应数据
//记录每个数据点的X、Y坐标
private var mDataPointList1: MutableList<PointF> = mutableListOf()
private var mDataPointList2: MutableList<PointF> = mutableListOf()
private var mXLabelList: MutableList<String> = mutableListOf() //X轴刻度值
private var mYLabelList: MutableList<String> = mutableListOf() //Y轴刻度值
init {
setLayerType(LAYER_TYPE_SOFTWARE, null) //关闭硬件加速，解决在部分手机无法实现虚线效果
attrs?.let {
parseAttribute(getContext(), it)
}
initPaint()
setYLable()
}
//初始化Y轴刻度值
private fun setYLable() {
mYLabelList.clear()
val increment = maxYValue / yLabelCount.toFloat()
for (i in 0..yLabelCount) {
var text = ""
if (i == 0) {
text = "0"
} else {
val value = (increment * i * 100).toInt() / 100f
if (value == value.toInt().toFloat()) {
text = value.toInt().toString()
} else {
text = value.toString()
}
}
mYLabelList.add(text)
}
}
//获取布局属性并设置属性默认值
private fun parseAttribute(context: Context, attrs: AttributeSet) {
val ta = context.obtainStyledAttributes(attrs, R.styleable.LineChart)
maxYValue = ta.getInt(R.styleable.LineChart_maxYValue, DEFAULT_MAX_YVALUE)
yLabelCount = ta.getInt(R.styleable.LineChart_yLabelCount, DEFAULT_YLABEL_COUNT)
xLabelTextSize = ta.getDimension(R.styleable.LineChart_xLabelTextSize, DEFAULT_XLABEL_TEXT_SIZE)
xLabelTextColor = ta.getColor(R.styleable.LineChart_xLabelTextColor, DEFAULT_XLABEL_TEXT_COLOR)
xLabelTextMarginTop = ta.getDimension(R.styleable.LineChart_xLabelTextMarginTop, DEFAULT_XLABEL_TEXT_MARGIN_TOP)
showYLabelText = ta.getBoolean(R.styleable.LineChart_showYLabelText, DEFAULT_SHOW_YLABEL_TEXT)
yLabelTextSize = ta.getDimension(R.styleable.LineChart_yLabelTextSize, DEFAULT_YLABEL_TEXT_SIZE)
yLabelTextColor = ta.getColor(R.styleable.LineChart_yLabelTextColor, DEFAULT_YLABEL_TEXT_COLOR)
yLabelTextMarginLeft = ta.getDimension(R.styleable.LineChart_yLabelTextMarginLeft, DEFAULT_YLABEL_TEXT_MARGIN_LEFT)
axisWidth = ta.getDimension(R.styleable.LineChart_axisWidth, DEFAULT_AXIS_WIDTH)
axisColor = ta.getColor(R.styleable.LineChart_axisColor, DEFAULT_AXIS_COLOR)
showScale = ta.getBoolean(R.styleable.LineChart_showScale, DEFAULT_SHOW_SCALE)
scaleLength = ta.getDimension(R.styleable.LineChart_scaleLength, DEFAULT_SCALE_LENGTH)
showGrid = ta.getBoolean(R.styleable.LineChart_showGrid, DEFAULT_SHOW_GRID)
gridWidth = ta.getDimension(R.styleable.LineChart_gridWidth, DEFAULT_GRID_WIDTH)
gridDashInterval = ta.getDimension(R.styleable.LineChart_gridDashInterval, DEFAULT_GRID_DASH_INTERVAL)
gridDashLength = ta.getDimension(R.styleable.LineChart_gridDashLength, DEFAULT_GRID_DASH_LENGTH)
gridColor = ta.getColor(R.styleable.LineChart_gridColor, DEFAULT_GRID_COLOR)
lineWidth = ta.getDimension(R.styleable.LineChart_lineWidth, DEFAULT_LINE_WIDTH)
lineColor1 = ta.getColor(R.styleable.LineChart_lineColor1, DEFAULT_LINE_COLOR1)
lineColor2 = ta.getColor(R.styleable.LineChart_lineColor2, DEFAULT_LINE_COLOR2)
labelWidth = ta.getDimension(R.styleable.LineChart_labelWidth, DEFAULT_LABEL_WIDTH)
labelHeight = ta.getDimension(R.styleable.LineChart_labelHeight, DEFAULT_LABEL_HEIGHT)
labelBackgroundColor = ta.getColor(R.styleable.LineChart_labelBackgroundColor, DEFAULT_LABEL_BACKGROUND_COLOR)
labelRadius = ta.getDimension(R.styleable.LineChart_labelRadius, DEFAULT_LABEL_RADIUS)
labelTextSize = ta.getDimension(R.styleable.LineChart_labelTextSize, DEFAULT_LABEL_TEXT_SIZE)
labelTextColor = ta.getColor(R.styleable.LineChart_labelTextColor, DEFAULT_LABEL_TEXT_COLOR)
labelArrowWidth = ta.getDimension(R.styleable.LineChart_labelArrowWidth, DEFAULT_LABEL_ARROW_WIDTH)
labelArrowHeight = ta.getDimension(R.styleable.LineChart_labelArrowHeight, DEFAULT_LABEL_ARROW_HEIGHT)
labelArrowOffset = ta.getDimension(R.styleable.LineChart_labelArrowMargin, DEFAULT_LABEL_ARROW_OFFSET)
labelArrowMargin = ta.getDimension(R.styleable.LineChart_labelArrowMargin, DEFAULT_LABEL_ARROW_MARGIN)
clickAble = ta.getBoolean(R.styleable.LineChart_clickAble, DEFAULT_CLICKABLE)
leftMargin = ta.getDimension(R.styleable.LineChart_leftMargin, DEFAULT_LEFT_MARGIN)
topMargin = ta.getDimension(R.styleable.LineChart_topMargin, DEFAULT_TOP_MARGIN)
rightMargin = ta.getDimension(R.styleable.LineChart_rightMargin, DEFAULT_RIGHT_MARGIN)
bottomMargin = ta.getDimension(R.styleable.LineChart_bottomMargin, DEFAULT_BOTTOM_MARGIN)
ta.recycle()
}
//初始化画笔
private fun initPaint() {
mAxisPaint = Paint()
with(mAxisPaint) {
isAntiAlias = true
color = axisColor
strokeWidth = axisWidth
}
mGridPaint = Paint()
with(mGridPaint) {
isAntiAlias = true
color = gridColor
strokeWidth = gridWidth
setPathEffect(DashPathEffect(floatArrayOf(gridDashLength, gridDashInterval), 0f)) //设置虚线效果
}
mLinePaint = Paint()
with(mLinePaint) {
isAntiAlias = true
strokeWidth = lineWidth
style = Paint.Style.STROKE
}
mLabelPaint = Paint()
with(mLabelPaint) {
isAntiAlias = true
}
mLabelBgPaint = Paint()
with(mLabelBgPaint) {
isAntiAlias = true
color = labelBackgroundColor
}
mTextPaint = Paint()
with(mTextPaint) {
isAntiAlias = true
textAlign = Paint.Align.CENTER
}
mLabelRectF = RectF()
}
override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec)
val heightMode = MeasureSpec.getMode(heightMeasureSpec)
val heightSize = MeasureSpec.getSize(heightMeasureSpec)
var height = 0
if (heightMode == MeasureSpec.EXACTLY) {
height = heightSize
} else {
height = SizeUtil.dp2px(308f).toInt()
if (heightMode == MeasureSpec.AT_MOST) {
height = Math.min(height, heightSize)
}
}
setMeasuredDimension(measuredWidth, height)
}
override fun onTouchEvent(event: MotionEvent?): Boolean {
val touchX = event?.getX() ?: 0f
for (i in 0..mDataPointList1.size - 1) {
val centerX = mDataPointList1[i].x
var beginX = centerX - mXScale / 2f
var endX = centerX + mXScale / 2f
if (i == 0) {
beginX = 0f
}
if (i == mDataPointList1.size - 1) {
endX = mWidth.toFloat()
}
if (beginX < touchX && touchX < endX) {
mClickIndex = i
invalidate()
break
}
}
return true
}
override fun onDraw(canvas: Canvas?) {
canvas?.let {
initSize(width, height) //初始化尺寸信息
drawCoordinate(it) //绘制坐标轴
drawLine(it) //绘制折线
drawLabel(it) //绘制点击后的效果
drawBottomDescription(it) //绘制底部类型说明
}
}
//初始化尺寸信息
private fun initSize(width: Int, height: Int) {
mWidth = width
mHeight = height
mXLength = mWidth - leftMargin - rightMargin
mYLength = mHeight - topMargin - bottomMargin
mXPoint = leftMargin
mYPoint = mHeight - bottomMargin
mXScale = mXLength / (mXLabelList.size - 1)
mYScale = mYLength / yLabelCount
mDataPointList1.clear()
if (hasOnlyOneData()) {
mDataPointList1.add(PointF(mXPoint + mXLength / 2f, calculateYPosition(mDataList1.get(0)))) //居中
} else {
for (i in 0..mDataList1.size - 1) {
mDataPointList1.add(PointF(mXPoint + i * mXScale, calculateYPosition(mDataList1.get(i))))
}
}
mDataPointList2.clear()
if (hasOnlyOneData()) {
mDataPointList2.add(PointF(mXPoint + mXLength / 2f, calculateYPosition(mDataList2.get(0)))) //居中
} else {
for (i in 0..mDataList2.size - 1) {
mDataPointList2.add(PointF(mXPoint + i * mXScale, calculateYPosition(mDataList2.get(i))))
}
}
}
//绘制坐标轴
private fun drawCoordinate(canvas: Canvas) {
//绘制X轴
canvas.drawLine(mXPoint - axisWidth / 2f, mYPoint, mXPoint + mXLength + axisWidth / 2f, mYPoint, mAxisPaint)
with(mTextPaint) {
textSize = xLabelTextSize
color = xLabelTextColor
}
val fm = mTextPaint.getFontMetrics()
val yOffset = mYPoint + xLabelTextMarginTop - fm.ascent
for (i in 0..mXLabelList.size - 1) {
//绘制X轴的刻度值文本
if (i == 0) { //第一个刻度值文本
if (hasOnlyOneData()) { //只有一条数据时居中显示
mTextPaint.textAlign = Paint.Align.CENTER
canvas.drawText(mXLabelList[i], mDataPointList1[i].x, yOffset, mTextPaint)
} else {
mTextPaint.textAlign = Paint.Align.LEFT
canvas.drawText(mXLabelList[i], mXPoint, yOffset, mTextPaint)
}
} else if (i == mXLabelList.size - 1) { //最后一个刻度值文本
mTextPaint.textAlign = Paint.Align.RIGHT
canvas.drawText(mXLabelList[i], mXPoint + mXLength, yOffset, mTextPaint)
} else {
mTextPaint.textAlign = Paint.Align.CENTER
canvas.drawText(mXLabelList[i], mXPoint + i * mXScale, yOffset, mTextPaint)
}
//绘制X轴上的小刻度线
if (showScale) {
canvas.drawLine(
mXPoint + i * mXScale,
mYPoint,
mXPoint + i * mXScale,
mYPoint - scaleLength,
mAxisPaint
)
}
}
for (i in 0..yLabelCount - 1) {
//绘制网格线：横刻线
if (showGrid) {
mGridPaint.color = gridColor
canvas.drawLine(
mXPoint,
mYPoint - (i + 1) * mYScale,
mXPoint + mXLength,
mYPoint - (i + 1) * mYScale,
mGridPaint
)
}
//绘制Y轴上的刻度值
if (showYLabelText) {
with(mTextPaint) {
textSize = yLabelTextSize
color = yLabelTextColor
textAlign = Paint.Align.LEFT
}
if (i == 0) {
canvas.drawText(mYLabelList[i], yLabelTextMarginLeft, mYPoint, mTextPaint)
}
val yLabelFm = mTextPaint.getFontMetrics()
val yLabelYOffset = mYPoint + (yLabelFm.descent - yLabelFm.ascent) / 2f - yLabelFm.descent - (i + 1) * mYScale
canvas.drawText(mYLabelList[i + 1], yLabelTextMarginLeft, yLabelYOffset, mTextPaint)
}
}
}
//绘制折线
private fun drawLine(canvas: Canvas) {
if (mDataList1 == null || mDataList1.size <= 0 || mDataList2 == null || mDataList2.size <= 0) {
return
}
if (hasOnlyOneData()) { //处理只有一条数据的情况
//绘制第一条直线
mLinePaint.color = lineColor1
canvas.drawLine(mXPoint, mDataPointList1[0].y, mXPoint + mXLength, mDataPointList1[0].y, mLinePaint)
//绘制第二条直线
mLinePaint.color = lineColor2
canvas.drawLine(mXPoint, mDataPointList2[0].y, mXPoint + mXLength, mDataPointList2[0].y, mLinePaint)
return
}
for (i in 0..mDataPointList1.size - 2) {
if (i <= mCurrentDrawIndex) {
//绘制第一条折线
//绘制折线
mLinePaint.color = lineColor1
canvas.drawLine(
mDataPointList1[i].x, mDataPointList1[i].y,
mDataPointList1[i + 1].x, mDataPointList1[i + 1].y, mLinePaint
)
//绘制折线交点
canvas.drawCircle(mDataPointList1[i].x, mDataPointList1[i].y, lineWidth * 1.5f, mLinePaint)
mLinePaint.color = Color.WHITE
canvas.drawCircle(mDataPointList1[i].x, mDataPointList1[i].y, lineWidth * 0.5f, mLinePaint)
//绘制第二条折线
//绘制折线
mLinePaint.color = lineColor2
canvas.drawLine(
mDataPointList2[i].x, mDataPointList2[i].y,
mDataPointList2[i + 1].x, mDataPointList2[i + 1].y, mLinePaint
)
//绘制折线交点
canvas.drawCircle(mDataPointList2[i].x, mDataPointList2[i].y, lineWidth * 1.5f, mLinePaint)
mLinePaint.color = Color.WHITE
canvas.drawCircle(mDataPointList2[i].x, mDataPointList2[i].y, lineWidth * 0.5f, mLinePaint)
//绘制最后一个折线交点
if (i == mDataPointList1.size - 2) {
mLinePaint.color = lineColor1
canvas.drawCircle(
mDataPointList1[mDataPointList1.size - 1].x,
mDataPointList1[mDataPointList1.size - 1].y,
lineWidth * 1.5f,
mLinePaint
)
mLinePaint.color = Color.WHITE
canvas.drawCircle(
mDataPointList1[mDataPointList1.size - 1].x,
mDataPointList1[mDataPointList1.size - 1].y,
lineWidth * 0.5f,
mLinePaint
)
mLinePaint.color = lineColor2
canvas.drawCircle(
mDataPointList2[mDataPointList2.size - 1].x,
mDataPointList2[mDataPointList2.size - 1].y,
lineWidth * 1.5f,
mLinePaint
)
mLinePaint.color = Color.WHITE
canvas.drawCircle(
mDataPointList2[mDataPointList2.size - 1].x,
mDataPointList2[mDataPointList2.size - 1].y,
lineWidth * 0.5f,
mLinePaint
)
}
}
}
}
//计算数值对应的Y坐标
private fun calculateYPosition(data: Float): Float = mYPoint - data / maxYValue * mYLength
//绘制点击后的详情展示
private fun drawLabel(canvas: Canvas) {
if (clickAble && mDataList1.size > 0) {
//绘制点击后的竖刻线
mLabelPaint.color = Color.parseColor("#EBEBEB")
mLabelPaint.strokeWidth = DEFAULT_GRID_WIDTH * 2
canvas.drawLine(
mDataPointList1[mClickIndex].x,
mYPoint,
mDataPointList1[mClickIndex].x,
topMargin - labelArrowMargin,
mLabelPaint
)
//绘制点击后的折线交点
mLabelPaint.color = lineColor1
canvas.drawCircle(
mDataPointList1[mClickIndex].x,
mDataPointList1[mClickIndex].y,
lineWidth * 2.3f,
mLabelPaint
)
mLabelPaint.color = lineColor2
canvas.drawCircle(
mDataPointList2[mClickIndex].x,
mDataPointList2[mClickIndex].y,
lineWidth * 2.3f,
mLabelPaint
)
//绘制最上方标签信息
with(mLabelRectF) {
bottom = topMargin - labelArrowMargin - labelArrowHeight
top = bottom - labelHeight;
left = mDataPointList1[mClickIndex].x - labelArrowWidth / 2f - labelArrowOffset
right = left + labelWidth
//处理点击第一项出现标签偏离整个折线图现象
if (left < 0) {
left = SizeUtil.dp2px(5f)
right = left + labelWidth
}
//处理点击最后一项出现标签偏离整个折线图现象
if (right > mWidth) {
right = mWidth.toFloat() - SizeUtil.dp2px(5f)
left = right - labelWidth
}
}
//绘制圆角矩形
mLabelBgPaint.setShadowLayer(
SizeUtil.dp2px(12f), //阴影效果
SizeUtil.dp2px(2.5f),
SizeUtil.dp2px(1.5f),
Color.parseColor("#C7C7C7")
)
canvas.drawRoundRect(mLabelRectF, labelRadius, labelRadius, mLabelBgPaint)
//绘制箭头
val arrowPath = Path()
with(arrowPath) {
moveTo(mDataPointList1[mClickIndex].x, topMargin - labelArrowMargin)
val baseY = topMargin - labelArrowMargin - labelArrowHeight - SizeUtil.dp2px(1f)
lineTo(mDataPointList1[mClickIndex].x - labelArrowWidth / 2f, baseY)
lineTo(mDataPointList1[mClickIndex].x + labelArrowWidth / 2f, baseY)
close()
}
mLabelPaint.color = labelBackgroundColor
canvas.drawPath(arrowPath, mLabelPaint)
mLabelPaint.color = Color.parseColor("#F1F1F1")
mLabelPaint.strokeWidth = gridWidth
canvas.drawLine(
mLabelRectF.left + SizeUtil.dp2px(10f),
mLabelRectF.bottom - SizeUtil.dp2px(52f),
mLabelRectF.right - SizeUtil.dp2px(10f),
mLabelRectF.bottom - SizeUtil.dp2px(52f), mLabelPaint
)
//绘制文字
with(mTextPaint) {
color = labelTextColor
textSize = labelTextSize
textAlign = Paint.Align.LEFT
}
canvas.drawText(
mXLabelList[mClickIndex],
mLabelRectF.left + SizeUtil.dp2px(9.5f),
mLabelRectF.bottom - SizeUtil.dp2px(61f), mTextPaint
)
canvas.drawText(
"交易收益 ?${mDataList1[mClickIndex]}",
mLabelRectF.left + SizeUtil.dp2px(19.5f),
mLabelRectF.bottom - SizeUtil.dp2px(32.5f), mTextPaint
)
canvas.drawText(
"返现收益 ?${mDataList2[mClickIndex]}",
mLabelRectF.left + SizeUtil.dp2px(19.5f),
mLabelRectF.bottom - SizeUtil.dp2px(12.5f), mTextPaint
)
mTextPaint.color = lineColor1
canvas.drawCircle(
mLabelRectF.left + SizeUtil.dp2px(12.5f),
mLabelRectF.bottom - SizeUtil.dp2px(36f),
SizeUtil.dp2px(2.5f), mTextPaint
)
mTextPaint.color = lineColor2
canvas.drawCircle(
mLabelRectF.left + SizeUtil.dp2px(12.5f),
mLabelRectF.bottom - SizeUtil.dp2px(16f),
SizeUtil.dp2px(2.5f), mTextPaint
)
}
}
//绘制底部类型说明
private fun drawBottomDescription(canvas: Canvas) {
if (mDataList1 == null || mDataList1.size == 0 || mDataList2 == null || mDataList2.size == 0) {
return
}
mTextPaint.color = lineColor1
val centerX1 = mWidth / 2f - SizeUtil.dp2px(75.5f)
canvas.drawCircle(
centerX1, mHeight - SizeUtil.dp2px(20f),
SizeUtil.dp2px(3.5f), mTextPaint
)
mTextPaint.color = lineColor2
val centerX2 = mWidth / 2f + SizeUtil.dp2px(16f)
canvas.drawCircle(
centerX2, mHeight - SizeUtil.dp2px(20f),
SizeUtil.dp2px(3.5f), mTextPaint
)
mTextPaint.color = Color.WHITE
canvas.drawCircle(
centerX1, mHeight - SizeUtil.dp2px(20f),
SizeUtil.dp2px(2.2f), mTextPaint
)
canvas.drawCircle(
centerX2, mHeight - SizeUtil.dp2px(20f),
SizeUtil.dp2px(2.2f), mTextPaint
)
with(mTextPaint) {
color = labelTextColor
textSize = SizeUtil.sp2px(12f)
}
canvas.drawText(
"交易收益", centerX1 + SizeUtil.dp2px(8f),
mHeight - SizeUtil.dp2px(15.5f), mTextPaint
)
canvas.drawText(
"返现收益", centerX2 + SizeUtil.dp2px(8f),
mHeight - SizeUtil.dp2px(15.5f), mTextPaint
)
}
//格式化标签内的数值文本
private fun formatValue(value: Float): String {
val scale = maxYValue / yLabelCount.toFloat()
if (scale < 10 && (value != value.toInt().toFloat()) && (value >= 0.01f)) {
return "${(value * 100).toInt().toFloat() / 100}" //保留2位小数，但不四舍五入
}
return "${value.toInt()}"
}
//是否只有一条数据
private fun hasOnlyOneData(): Boolean = mDataList1.size == 1 && mDataList2.size == 1 && mXLabelList.size == 1
//设置数据，startAnim：是否开启动画，动画默认一条一条折线的画
//list1和list2的数据个数要相同，dateList的数据个数大于等于list1和list2的数据个数
fun drawData(list1: MutableList<Float>, list2: MutableList<Float>, dateList: MutableList<String>, startAnim: Boolean = false) {
if (list1.size != list2.size) {
throw RuntimeException("the size of list1 must be equal to the size of list2")
}
if (dateList.size < list1.size) {
throw RuntimeException("the size of dateList can not less than the size of list1")
}
var maxValue = 0f
for (item in list1) {
if (maxValue <= item) {
maxValue = item
}
}
for (item in list2) {
if (maxValue <= item) {
maxValue = item
}
}
mDataList1 = list1
mDataList2 = list2
mXLabelList = dateList
maxYValue = calculateMaxValue(maxValue)
mClickIndex = 0
setYLable() //重新设置Y轴刻度值
if (startAnim) {
val animator = ValueAnimator.ofInt(0, mDataList1.size - 2)
animator.setDuration(1500)
animator.addUpdateListener {
mCurrentDrawIndex = it.getAnimatedValue() as Int
invalidate()
}
animator.interpolator = LinearInterpolator()
animator.start()
} else {
mCurrentDrawIndex = mDataList1.size - 2
invalidate()
}
}
//计算Y轴最大值和单位，计算规则：最高位数加1取整
private fun calculateMaxValue(value: Float): Int {
val valueStr = value.toLong().toString()
val length = valueStr.length //整数的位数
val unit = Math.pow(10.0, (length - 1).toDouble()).toInt()
if (value == 0f) {
return DEFAULT_MAX_YVALUE //如果最大值是0，即所有数据都是0，取默认的最大值
} else if (value % unit == 0f) {
return value.toInt()
} else {
return ((value / unit).toInt() + 1) * unit
}
}
}
使用举例：
private fun createType2Data(count: Int, isDateMore: Boolean = false, startAnim: Boolean = false, showYLabelText: Boolean = false) {
val list1: MutableList<Float> = mutableListOf()
val list2: MutableList<Float> = mutableListOf()
val dateList: MutableList<String> = mutableListOf()
for (i in 0..count) {
list1.add(Random.nextDouble(80.0).toFloat())
list2.add(Random.nextDouble(80.0).toFloat())
dateList.add(DateUtil.getDistanceDateByDay(i - count, DateUtil.M_D))
}
if (isDateMore) {
dateList.add(DateUtil.getDistanceDateByDay(1, DateUtil.M_D))
}
if (showYLabelText) {
binding.type2Lc.leftMargin = SizeUtil.dp2px(40f)
} else {
binding.type2Lc.leftMargin = SizeUtil.dp2px(15f)
}
binding.type2Lc.showYLabelText = showYLabelText
binding.type2Lc.drawData(list1, list2, dateList, startAnim)
}