先看图
BrokenLine.png
分析图表
首先我们根据上图我们可以看到如下几个元素
- 边框线
![5FXGL_@$E{Y)R{}L~1V$]7R.png](http://upload-images.jianshu.io/upload_images/6544862-a5cc5c5619226bea.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
- 边框线数据值
BrokenLineData.png
- 边框线内折线
Line.png
- 折线上的圆
如上分析，我们所需要绘制的就是边框线，框线分段数据值，框内折线，折线上的圆
在画图之前 我们首先得 准备一些 必要参数
<code>
/**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;
/**圆画笔*/
private Paint mCirclePaint;
/**圆的半径*/
private float radius=5;
/**边框的左边距*/
private float mBrokenLineLeft=40;
/**边框的上边距*/
private float mBrokenLineTop=40;
/**边框的下边距*/
private float mBrokenLineBottom=40;
/**边框的右边距*/
private float mBrokenLinerRight=20;
/**需要绘制的宽度*/
private float mNeedDrawWidth;
/**需要绘制的高度*/
private float mNeedDrawHeight;
/**边框文本*/
private int[] valueText =new int[]{40,30,20,10,0};
/**数据值*/
private int[] value=new int[]{11,10,15,12,34,12,22,23,33,13};
/**图表的最大值*/
private int maxVlaue=40;
</code>
参数准备好 首先 重写onMeasure 初始化参数
<code>
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
mViewHeight = getMeasuredHeight();
mViewWidth = getMeasuredWidth();
initNeedDrawWidthAndHeight();
initPaint();
}
/**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() {
/**初始化文本画笔*/
if(mTextPaint==null){
mTextPaint=new Paint();
}
initPaint(mTextPaint);
/**初始化边框线画笔*/
if(mBorderLinePaint==null){
mBorderLinePaint=new Paint();
mBorderLinePaint.setTextSize(20);
}
initPaint(mBorderLinePaint);
/**初始化折线画笔*/
if(mBrokenLinePaint==null){
mBrokenLinePaint=new Paint();
}
initPaint(mBrokenLinePaint);
if(mCirclePaint==null){
mCirclePaint=new Paint();
}
initPaint(mCirclePaint);
}
/**初始化画笔默认属性*/
private void initPaint(Paint paint){
paint.setAntiAlias(true);
paint.setStyle(Paint.Style.STROKE);
paint.setColor(Color.BLACK);
}
</code>
这个时候我们的一切参数 都准备好了 首先我们来完成边线框的绘制
![5FXGL_@$E{Y)R{}L~1V$]7R.png](http://upload-images.jianshu.io/upload_images/6544862-a5cc5c5619226bea.png?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)
<code>
/**绘制边框竖线*/
canvas.drawLine(mBrokenLineLeft,mBrokenLineTop-10,mBrokenLineLeft,mViewHeight-mBrokenLineBottom,mBorderLinePaint);
/**绘制边框横线*/
canvas.drawLine(mBrokenLineLeft,mViewHeight-mBrokenLineBottom,mViewWidth,mViewHeight-mBrokenLineBottom,mBorderLinePaint);
</code>
边线框值的绘制
BrokenLineData.png
<code>
/**绘制边线框的值*/
float averageHeight=mNeedDrawHeight/(valueText.length-1);
mBorderLinePaint.setTextAlign(Paint.Align.RIGHT);
mBorderLinePaint.setColor(Color.GRAY);
for (int i = 0; i < valueText.length; i++) {
float nowadayHeight= averageHeight*i;
canvas.drawLine(mBrokenLineLeft,nowadayHeight+mBrokenLineTop,mViewWidth-mBrokenLinerRight,nowadayHeight+mBrokenLineTop,mBorderLinePaint);
canvas.drawText(valueText[i]+"",mBrokenLineLeft-5,nowadayHeight+mBrokenLineTop,mBorderLinePaint);
}
</code>
绘制框内的线
Line.png
<code>
/**根据值绘制折线*/
private void DrawBrokenLine(Canvas canvas) {
Path mPath=new Path();
mBrokenLinePaint.setColor(Color.BLUE);
mBrokenLinePaint.setStrokeWidth(2);
Point[] points= getPoints(value,mNeedDrawHeight,mNeedDrawWidth,maxVlaue,mBrokenLineLeft,mBrokenLineTop);
for (int i = 0; i < points.length; i++) {
Point point=points[i];
if(i==0){
mPath.moveTo(point.x,point.y);
}else {
mPath.lineTo(point.x,point.y);
}
}
canvas.drawPath(mPath,mBrokenLinePaint);
}
/**根据值计算在该值的 x，y坐标*/
public Point[] getPoints(int[] values, float height, float width, int max , 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++) {
float value = values[i];
//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>
绘制线上的圆
<code>
/**绘制线上的圆*/
private void DrawLineCircle(Canvas canvas) {
Point[] points= getPoints(value,mNeedDrawHeight,mNeedDrawWidth,maxVlaue,mBrokenLineLeft,mBrokenLineTop);
for (int i = 0; i <points.length ; i++) {
Point point=points[i];
mCirclePaint.setColor(Color.WHITE);
mCirclePaint.setStyle(Paint.Style.FILL);
canvas.drawCircle(point.x,point.y,radius,mCirclePaint);
mCirclePaint.setColor(Color.BLUE);
mCirclePaint.setStyle(Paint.Style.STROKE);
mCirclePaint.setStrokeWidth(3);
/**
* 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);
}
}
</code>
那么完整的代码如下
<code>
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;
public class BrokenLineChart extends View {
private static final String TAG = "BrokenLineChart";
/**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;
/**圆画笔*/
private Paint mCirclePaint;
/**圆的半径*/
private float radius=5;
/**边框的左边距*/
private float mBrokenLineLeft=40;
/**边框的上边距*/
private float mBrokenLineTop=40;
/**边框的下边距*/
private float mBrokenLineBottom=40;
/**边框的右边距*/
private float mBrokenLinerRight=20;
/**需要绘制的宽度*/
private float mNeedDrawWidth;
/**需要绘制的高度*/
private float mNeedDrawHeight;
/**边框文本*/
private int[] valueText =new int[]{40,30,20,10,0};
/**数据值*/
private int[] value=new int[]{11,10,15,12,34,12,22,23,33,13};
/**图表的最大值*/
private int maxVlaue=40;
public BrokenLineChart(Context context) {
super(context);
}
public BrokenLineChart(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
mViewHeight = getMeasuredHeight();
mViewWidth = getMeasuredWidth();
initNeedDrawWidthAndHeight();
initPaint();
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
/**绘制边框线和边框文本*/
DrawBorderLineAndText(canvas);
/**根据数据绘制线*/
DrawBrokenLine(canvas);
DrawLineCircle(canvas);
}
/**绘制线上的圆*/
private void DrawLineCircle(Canvas canvas) {
Point[] points= getPoints(value,mNeedDrawHeight,mNeedDrawWidth,maxVlaue,mBrokenLineLeft,mBrokenLineTop);
for (int i = 0; i <points.length ; i++) {
Point point=points[i];
mCirclePaint.setColor(Color.WHITE);
mCirclePaint.setStyle(Paint.Style.FILL);
canvas.drawCircle(point.x,point.y,radius,mCirclePaint);
mCirclePaint.setColor(Color.BLUE);
mCirclePaint.setStyle(Paint.Style.STROKE);
mCirclePaint.setStrokeWidth(3);
/**
* 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*/
private void DrawBrokenLine(Canvas canvas) {
Path mPath=new Path();
mBrokenLinePaint.setColor(Color.BLUE);
mBrokenLinePaint.setStrokeWidth(2);
Point[] points= getPoints(value,mNeedDrawHeight,mNeedDrawWidth,maxVlaue,mBrokenLineLeft,mBrokenLineTop);
for (int i = 0; i < points.length; i++) {
Point point=points[i];
if(i==0){
mPath.moveTo(point.x,point.y);
}else {
mPath.lineTo(point.x,point.y);
}
}
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
* */
mBorderLinePaint.setColor(Color.BLACK);
/**绘制边框竖线*/
canvas.drawLine(mBrokenLineLeft,mBrokenLineTop-10,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/(valueText.length-1);
mBorderLinePaint.setTextAlign(Paint.Align.RIGHT);
mBorderLinePaint.setColor(Color.GRAY);
for (int i = 0; i < valueText.length; i++) {
float nowadayHeight= averageHeight*i;
canvas.drawLine(mBrokenLineLeft,nowadayHeight+mBrokenLineTop,mViewWidth-mBrokenLinerRight,nowadayHeight+mBrokenLineTop,mBorderLinePaint);
canvas.drawText(valueText[i]+"",mBrokenLineLeft-5,nowadayHeight+mBrokenLineTop,mBorderLinePaint);
}
}
/**初始化画笔*/
private void initPaint() {
/**初始化文本画笔*/
if(mTextPaint==null){
mTextPaint=new Paint();
}
initPaint(mTextPaint);
/**初始化边框线画笔*/
if(mBorderLinePaint==null){
mBorderLinePaint=new Paint();
mBorderLinePaint.setTextSize(20);
}
initPaint(mBorderLinePaint);
/**初始化折线画笔*/
if(mBrokenLinePaint==null){
mBrokenLinePaint=new Paint();
}
initPaint(mBrokenLinePaint);
if(mCirclePaint==null){
mCirclePaint=new Paint();
}
initPaint(mCirclePaint);
}
/**初始化画笔默认属性*/
private void initPaint(Paint paint){
paint.setAntiAlias(true);
paint.setStyle(Paint.Style.STROKE);
paint.setColor(Color.BLACK);
}
/**初始化绘制折线图的宽高*/
private void initNeedDrawWidthAndHeight(){
mNeedDrawWidth = mViewWidth-mBrokenLineLeft-mBrokenLinerRight;
mNeedDrawHeight = mViewHeight-mBrokenLineTop-mBrokenLineBottom;
}
/**根据值计算在该值的 x，y坐标*/
public Point[] getPoints(int[] values, float height, float width, int max , 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++) {
float value = values[i];
//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>
