Android 曲线图
Paste_Image.png
这里我引用了上回介绍的 折线图
首先我们看看onDrwa 里面做了什么 从图里面我们可看到 绘制的框线方法，绘制data线方法 绘制线上的圆
从最上面的图效果来看我们不需要圆 也不需要折线，但是框线要保留 因此我们需要 把
这个几个方法 改成public ，到时候继承之后重写他 不调用父方法即可
Paste_Image.png
Paste_Image.png
接下来我们创建一个 类继承 DrawLineChart 重写 DrawLineCircle，DrawLine 方法
这样我们就保留 了框线， 取消了圆和折线的绘制
接下来在DrawLine 里面绘制曲线
<code>
@Override
public void DrawLine(Canvas canvas) {
Path mPath=new Path();
for(int j = 0; j < mPoints.length; j++) {
Point startp = mPoints[j];
Point endp;
if (j != mPoints.length - 1) {
endp = mPoints[j + 1];
int wt = (startp.x + endp.x) / 2;
Point p3 = new Point();
Point p4 = new Point();
p3.y = startp.y;
p3.x = wt;
p4.y = endp.y;
p4.x = wt;
if (j == 0) {
mPath.moveTo(startp.x, startp.y);
}
/**
*添加一个立方贝塞尔曲线的最后一点,接近控制点
*(x1,y1)和(x2,y2),到最后(x3,y3)。如果没有移至()调用
*为这个轮廓,第一点是自动设置为(0,0)。
*
* @param x1的坐标1立方曲线控制点
* @param y1第一控制点的坐标一立方曲线
* @param x2上第二个控制点的坐标一立方曲线
* @param y2第二控制点的坐标一立方曲线
* @param x3的坐标三次曲线的终点
* @param y3终点坐标的三次曲线
*
*/
mPath.cubicTo(p3.x, p3.y, p4.x, p4.y, endp.x, endp.y);
}
}
/**这里直接使用了折线的画笔，你也可以在此类在定义一个画笔*/
canvas.drawPath(mPath,getBrokenLinePaint());
}
</code>
什么， 你不光要曲线，。 还要填充式的怎么办，这个时候你就需要将你的曲线连接起来 起点到终点连接起来 将画笔Style 改为FILL ，怎么连？ 看图，从图上 我们可以看到
- 终点x,终点y 连接到 终点x,底部y
- 终点x,底部y 连接到 起点x,底部y
- 起点x 底部y 连接到 起点x,起点y
Paste_Image.png
- 根据上面的分析 我们代码 就是这样的了
<code>
@Override
public void DrawLine(Canvas canvas) {
Path mPath=new Path();
for(int j = 0; j < mPoints.length; j++) {
Point startp = mPoints[j];
Point endp;
if (j != mPoints.length - 1) {
endp = mPoints[j + 1];
int wt = (startp.x + endp.x) / 2;
Point p3 = new Point();
Point p4 = new Point();
p3.y = startp.y;
p3.x = wt;
p4.y = endp.y;
p4.x = wt;
if (j == 0) {
mPath.moveTo(startp.x, startp.y);
}
/**
*添加一个立方贝塞尔曲线的最后一点,接近控制点
*(x1,y1)和(x2,y2),到最后(x3,y3)。如果没有移至()调用
*为这个轮廓,第一点是自动设置为(0,0)。
*
* @param x1的坐标1立方曲线控制点
* @param y1第一控制点的坐标一立方曲线
* @param x2上第二个控制点的坐标一立方曲线
* @param y2第二控制点的坐标一立方曲线
* @param x3的坐标三次曲线的终点
* @param y3终点坐标的三次曲线
*
*/
mPath.cubicTo(p3.x, p3.y, p4.x, p4.y, endp.x, endp.y);
}else {
/**连接到终点x,底部y*/
mPath.lineTo(startp.x,getNeedDrawHeight()+getBrokenLineTop());
/**连接到起点x,底部y*/
mPath.lineTo(mPoints[0].x,getNeedDrawHeight()+getBrokenLineTop());
/**连接到起点x,起点y*/
mPath.lineTo(mPoints[0].x,mPoints[0].y);
}
}
Paint paint=getBrokenLinePaint();
/**修改画笔属性*/
paint.setStyle(Paint.Style.FILL);
canvas.drawPath(mPath,getBrokenLinePaint());
}
</code>
- 效果图
Paste_Image.png
完整代码
<code>
package com.app_chart;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Point;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
public class CurveChart extends DrawLineChart {
public CurveChart(Context context) {
super(context);
}
public CurveChart(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
}
@Override
public void DrawLineCircle(Canvas canvas) {
}
@Override
public void DrawLine(Canvas canvas) {
Path mPath=new Path();
for(int j = 0; j < mPoints.length; j++) {
Point startp = mPoints[j];
Point endp;
if (j != mPoints.length - 1) {
endp = mPoints[j + 1];
int wt = (startp.x + endp.x) / 2;
Point p3 = new Point();
Point p4 = new Point();
p3.y = startp.y;
p3.x = wt;
p4.y = endp.y;
p4.x = wt;
if (j == 0) {
mPath.moveTo(startp.x, startp.y);
}
/**
*添加一个立方贝塞尔曲线的最后一点,接近控制点
*(x1,y1)和(x2,y2),到最后(x3,y3)。如果没有移至()调用
*为这个轮廓,第一点是自动设置为(0,0)。
*
* @param x1的坐标1立方曲线控制点
* @param y1第一控制点的坐标一立方曲线
* @param x2上第二个控制点的坐标一立方曲线
* @param y2第二控制点的坐标一立方曲线
* @param x3的坐标三次曲线的终点
* @param y3终点坐标的三次曲线
*
*/
mPath.cubicTo(p3.x, p3.y, p4.x, p4.y, endp.x, endp.y);
}else {
/**连接到终点x,底部y*/
mPath.lineTo(startp.x,getNeedDrawHeight()+getBrokenLineTop());
/**连接到起点x,底部y*/
mPath.lineTo(mPoints[0].x,getNeedDrawHeight()+getBrokenLineTop());
/**连接到起点x,起点y*/
mPath.lineTo(mPoints[0].x,mPoints[0].y);
}
}
Paint paint=getBrokenLinePaint();
/**修改画笔属性*/
paint.setStyle(Paint.Style.FILL);
canvas.drawPath(mPath,getBrokenLinePaint());
}
}
</code>
Activity 调用
Paste_Image.png
DrawLineChart 代码
<code>
package com.app_chart;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Point;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
import android.view.View;
import java.text.DecimalFormat;
public class DrawLineChart extends View {
private static final String TAG = "DrawLineChart";
/**View宽度*/
private int mViewWidth;
/** View高度*/
private int mViewHeight;
/**边框线画笔*/
private Paint mBorderLinePaint;
/**文本画笔*/
private Paint mTextPaint;
/**要绘制的折线线画笔*/
private Paint mBrokenLinePaint;
/**折线文本画笔*/
private Paint mBrokenLineTextPaint;
/**圆画笔*/
private Paint mCirclePaint;
/**横线画笔*/
private Paint mHorizontalLinePaint;
/**圆的厚度*/
private float mCircleWidth=2;
/**圆的半径*/
private float radius=5;
/**边框的左边距*/
private float mBrokenLineLeft=dip2px(30);
/**边框的上边距*/
private float mBrokenLineTop=dip2px(10);
/**边框的下边距*/
private float mBrokenLineBottom=dip2px(20);
/**边框的右边距*/
private float mBrokenLinerRight=dip2px(10);
/**需要绘制的宽度*/
private float mNeedDrawWidth;
/**需要绘制的高度*/
private float mNeedDrawHeight;
/**数据值*/
private float[] value=new float[]{-5.55f,-6.899f,-4.55f,-0.045f,21.511f,22.221f,22.330f,21.448f,21.955f,23.6612f,22,22.18883f,21.47995f};
/**图表的最大值*/
private float maxVlaue=27.55f;
/**图表的最小值*/
private float minValue=-19.12f;
/**要计算的总值*/
private float calculateValue;
/**框线平均值*/
private float averageValue;
/**横线数量*/
private float numberLine=5;
/**边框线颜色*/
private int mBorderLineColor=Color.BLACK;
/**边框线的宽度*/
private int mBorderWidth=2;
/**边框文本颜色*/
private int mBorderTextColor=Color.GRAY;
/**边框文本大小*/
private float mBorderTextSize=20;
/**边框横线颜色*/
private int mBorderTransverseLineColor=Color.GRAY;
/**边框横线宽度*/
private float mBorderTransverseLineWidth=2;
/**折线颜色*/
private int mBrokenLineColor=Color.BLUE;
/**折线文本颜色*/
private int mBrokenLineTextColor=Color.BLUE;
/**折线宽度*/
private float mBrokenLineWidth=2;
/**折线文本大小*/
private float mBrokenLineTextSize=15;
/**折线圆的颜色*/
private int mCircleColor=Color.BLUE;
/**计算后的x，y坐标*/
public Point[] mPoints;
/**圆的半径*/
public void setRadius(float radius) {
this.radius = dip2px(radius);
}
/**设置宽度*/
public void setCircleWidth(float circleWidth){
this.mCircleWidth=dip2px(circleWidth);
}
/**设置边框左上右下边距*/
public void setBrokenLineLTRB(float l,float t,float r,float b){
mBrokenLineLeft=dip2px(l);
mBrokenLineTop=dip2px(t);
mBrokenLinerRight=dip2px(r);
mBrokenLineBottom=dip2px(b);
}
public int getViewWidth() {
return mViewWidth;
}
public int getViewHeight() {
return mViewHeight;
}
public float getCircleWidth() {
return mCircleWidth;
}
public float getRadius() {
return radius;
}
public float getBrokenLineLeft() {
return mBrokenLineLeft;
}
public float getBrokenLineTop() {
return mBrokenLineTop;
}
public float getBrokenLineBottom() {
return mBrokenLineBottom;
}
public float getBrokenLinerRight() {
return mBrokenLinerRight;
}
public float getNeedDrawWidth() {
return mNeedDrawWidth;
}
public float getNeedDrawHeight() {
return mNeedDrawHeight;
}
public Point[] getPoints() {
return mPoints;
}
/**数据data*/
public void setValue(float[] value) {
this.value = value;
}
/**图表显示最大值*/
public void setMaxVlaue(float maxVlaue) {
this.maxVlaue = maxVlaue;
}
/**图表显示最小值*/
public void setMinValue(float minValue) {
this.minValue = minValue;
}
/**图表横线数量*/
public void setNumberLine(float numberLine) {
this.numberLine = numberLine;
}
/**边框线颜色*/
public void setBorderLineColor(int borderLineColor) {
mBorderLineColor = borderLineColor;
}
/**边框文本颜色*/
public void setBorderTextColor(int borderTextColor) {
mBorderTextColor = borderTextColor;
}
/**边框文本大小*/
public void setBorderTextSize(float borderTextSize) {
mBorderTextSize = dip2px(borderTextSize);
}
/**框线横线 颜色*/
public void setBorderTransverseLineColor(int borderTransverseLineColor) {
mBorderTransverseLineColor = borderTransverseLineColor;
}
/**边框内折线颜色*/
public void setBrokenLineColor(int brokenLineColor) {
mBrokenLineColor = brokenLineColor;
}
/** 折线文本颜色*/
public void setBrokenLineTextColor(int brokenLineTextColor) {
mBrokenLineTextColor = brokenLineTextColor;
}
/**折线文本大小*/
public void setBrokenLineTextSize(float brokenLineTextSize) {
mBrokenLineTextSize = dip2px(brokenLineTextSize);
}
/**折线圆颜色*/
public void setCircleColor(int circleColor) {
mCircleColor = dip2px(circleColor);
}
/**边框线宽度*/
public void setBorderWidth(float borderWidth) {
mBorderWidth = dip2px(borderWidth);
}
/**边框横线宽度*/
public void setBorderTransverseLineWidth(float borderTransverseLineWidth) {
mBorderTransverseLineWidth = dip2px(borderTransverseLineWidth);
}
/**折线宽度*/
public void setBrokenLineWidth(float brokenLineWidth) {
mBrokenLineWidth = dip2px(brokenLineWidth);
}
/**获取框线画笔*/
public Paint getBorderLinePaint() {
return mBorderLinePaint;
}
/**获取边框文本画笔*/
public Paint getTextPaint() {
return mTextPaint;
}
/**获取折线画笔*/
public Paint getBrokenLinePaint() {
return mBrokenLinePaint;
}
/**获取折线文本画笔*/
public Paint getBrokenLineTextPaint() {
return mBrokenLineTextPaint;
}
/**获取圆画笔*/
public Paint getCirclePaint() {
return mCirclePaint;
}
/**获取边框横线画笔*/
public Paint getHorizontalLinePaint() {
return mHorizontalLinePaint;
}
/**
* 将dip或dp值转换为px值，保证尺寸大小不变
*
* @param dipValue
* @return
*/
private int dip2px( float dipValue) {
final float scale = getContext().getResources().getDisplayMetrics().density;
return (int) (dipValue * scale + 0.5f);
}
public DrawLineChart(Context context) {
super(context);
initPaint();
}
public DrawLineChart(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
initPaint();
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
mViewHeight = getMeasuredHeight();
mViewWidth = getMeasuredWidth();
/**计算总值*/
calculateValue=maxVlaue-minValue;
initNeedDrawWidthAndHeight();
/**计算框线横线间隔的数据平均值*/
averageValue = calculateValue/(numberLine-1);
}
/**初始化绘制折线图的宽高*/
private void initNeedDrawWidthAndHeight(){
mNeedDrawWidth = mViewWidth-mBrokenLineLeft-mBrokenLinerRight;
mNeedDrawHeight = mViewHeight-mBrokenLineTop-mBrokenLineBottom;
}
/**初始化画笔*/
private void initPaint() {
/**初始化边框文本画笔*/
if(mTextPaint==null){
mTextPaint=new Paint();
initPaint(mTextPaint);
}
mTextPaint.setTextSize(mBorderTextSize);
mTextPaint.setTextAlign(Paint.Align.RIGHT);
mTextPaint.setColor(Color.GRAY);
/**初始化边框线画笔*/
if(mBorderLinePaint==null){
mBorderLinePaint=new Paint();
initPaint(mBorderLinePaint);
}
mBorderLinePaint.setTextSize(mBorderTextSize);
mBorderLinePaint.setStrokeWidth(mBorderWidth);
mBorderLinePaint.setColor(mBorderLineColor);
/**初始化折线画笔*/
if(mBrokenLinePaint==null){
mBrokenLinePaint=new Paint();
initPaint(mBrokenLinePaint);
}
mBrokenLinePaint.setStrokeWidth(mBrokenLineWidth);
mBrokenLinePaint.setColor(mBrokenLineColor);
if(mCirclePaint==null){
mCirclePaint=new Paint();
initPaint(mCirclePaint);
}
mCirclePaint.setStrokeWidth(mCircleWidth);
mCirclePaint.setColor(mCircleColor);
/**折线文本画笔*/
if (mBrokenLineTextPaint == null){
mBrokenLineTextPaint=new Paint();
initPaint(mBrokenLineTextPaint);
}
mBrokenLineTextPaint.setTextAlign(Paint.Align.CENTER);
mBrokenLineTextPaint.setColor(mBrokenLineTextColor);
mBrokenLineTextPaint.setTextSize(mBrokenLineTextSize);
/**横线画笔*/
if (mHorizontalLinePaint == null){
mHorizontalLinePaint=new Paint();
initPaint(mHorizontalLinePaint);
}
mHorizontalLinePaint.setStrokeWidth(mBorderTransverseLineWidth);
mHorizontalLinePaint.setColor(mBorderTransverseLineColor);
}
/**初始化画笔默认属性*/
private void initPaint(Paint paint){
paint.setAntiAlias(true);
paint.setStyle(Paint.Style.STROKE);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
mPoints = getPoints(value,mNeedDrawHeight,mNeedDrawWidth,calculateValue,minValue,mBrokenLineLeft,mBrokenLineTop);
/**绘制边框线和边框文本*/
DrawBorderLineAndText(canvas);
/**根据数据绘制线*/
DrawLine(canvas);
/**绘制圆*/
DrawLineCircle(canvas);
}
/**绘制线上的圆*/
public void DrawLineCircle(Canvas canvas) {
for (int i = 0; i <mPoints.length ; i++) {
Point point=mPoints[i];
mCirclePaint.setColor(Color.WHITE);
mCirclePaint.setStyle(Paint.Style.FILL);
canvas.drawCircle(point.x,point.y,radius,mCirclePaint);
mCirclePaint.setColor(mCircleColor);
mCirclePaint.setStyle(Paint.Style.STROKE);
/**
* drawCircle(float cx, float cy, float radius, Paint paint)
* cx 中间x坐标
* xy 中间y坐标
* radius 圆的半径
* paint 绘制圆的画笔
* */
canvas.drawCircle(point.x,point.y,radius,mCirclePaint);
}
}
/**根据值绘制折线*/
public void DrawLine(Canvas canvas) {
Path mPath=new Path();
for (int i = 0; i < mPoints.length; i++) {
Point point=mPoints[i];
if(i==0){
mPath.moveTo(point.x,point.y);
}else {
mPath.lineTo(point.x,point.y);
}
canvas.drawText(value[i]+"",point.x,point.y-radius,mBrokenLineTextPaint);
}
canvas.drawPath(mPath,mBrokenLinePaint);
}
/**绘制边框线和边框文本*/
private void DrawBorderLineAndText(Canvas canvas) {
/**对应的属性
* drawLine(float startX, float startY, float stopX, float stopY, Paint paint);
* startX 开始的x坐标
* startY 开始的y坐标
* stopX 结束的x坐标
* stopY 结束的y坐标
* paint 绘制该线的画笔
* */
/**绘制边框竖线*/
canvas.drawLine(mBrokenLineLeft,mBrokenLineTop-dip2px(5),mBrokenLineLeft,mViewHeight-mBrokenLineBottom,mBorderLinePaint);
/**绘制边框横线*/
canvas.drawLine(mBrokenLineLeft,mViewHeight-mBrokenLineBottom,mViewWidth,mViewHeight-mBrokenLineBottom,mBorderLinePaint);
/**绘制边框分段横线与分段文本*/
float averageHeight=mNeedDrawHeight/(numberLine-1);
for (int i = 0; i < numberLine; i++) {
float nowadayHeight= averageHeight*i;
float v=averageValue*(numberLine-1-i)+minValue;
/**最后横线无需绘制，否则会将边框横线覆盖*/
if(i!=numberLine-1) {
canvas.drawLine(mBrokenLineLeft, nowadayHeight + mBrokenLineTop, mViewWidth, nowadayHeight + mBrokenLineTop, mHorizontalLinePaint);
}
canvas.drawText(floatKeepTwoDecimalPlaces(v)+"",mBrokenLineLeft-dip2px(2),nowadayHeight+mBrokenLineTop,mTextPaint);
}
/**竖线*/
for (int i = 1; i < mPoints.length; i++) {
//canvas.drawLine(mPoints[i].x,mBrok enLineTop,mPoints[i].x,mBrokenLineTop+mNeedDrawHeight,mBorderLinePaint);
}
}
/**保留2位小数*/
private String floatKeepTwoDecimalPlaces(float f){
DecimalFormat decimalFormat=new DecimalFormat("0.00");//构造方法的字符格式这里如果小数不足2位,会以0补足.
String p=decimalFormat.format(f);
return p;
}
/**根据值计算在该值的 x，y坐标*/
public Point[] getPoints(float[] values, float height, float width, float max ,float min, float left,float top) {
float leftPading = width / (values.length-1);//绘制边距
Point[] points = new Point[values.length];
for (int i = 0; i < values.length; i++) {
double value = values[i]-min;
//计算每点高度所以对应的值
double mean = (double) max/height;
//获取要绘制的高度
float drawHeight = (float) (value / mean);
int pointY = (int) (height+top - drawHeight);
int pointX = (int) (leftPading * i + left);
Point point = new Point(pointX, pointY);
points[i] = point;
}
return points;
}
}
</code>
