演示效果
实现步骤：
1.画不同宽度和半径的内外圆弧
2.通过循环旋转canvas，在固定位置绘制短线刻度，长线刻度，刻度文字
3.绘制view中心几个文本，并调整位置
4.实时更新当前旋转角度刷新小圆点位置；
5.判断分数应该坐落的区间，再根据该区间的角度比例获取实际的角度。
6.用ObjectAnimator实现滚动文字
步骤代码讲解：
- 这里是声明的变量及常量
/** 圆环paint */
private Paint ringPaint;
/** 信用分文字paint */
private Paint scoreTextPaint;
/** 指示器paint */
private Paint dotPaint;
/** 外圆环宽度 */
private int outerRingWidth;
/** 内圆环宽度 */
private int innerRingWidth;
/** 表盘圆环总度数 */
private final int totalAngle = 210;
/** 圆弧上总共刻度数 */
private final int totalDegreeScale = 30;
/** 各分数刻度文本 */
private String[] scores = new String[] {"350", "较差", "550", "中等", "600", "良好", "650", "优秀", "700", "极好", "950"};
/** 信用分数 */
private int score = 715;
/** 当前扫过的数值角度 */
private float curProgressAngle;
/** 动画时长 */
private final long ANIM_DURATION = 2000;
/** 指示器结束时的角度 */
private float stopAngle;
/** 信用评级文字 */
private String creditStr;
绘制外层两个圆弧，以12点钟为圆弧中点，左右各有105°
private void drawRing (Canvas canvas) {
ringPaint.setAlpha(80);
int startAngle = -90-totalAngle/2; //圆环起始角度，12点钟位置为-90°
//绘制外圆环
ringPaint.setStrokeWidth(outerRingWidth);
RectF rectF = new RectF(outerRingWidth, outerRingWidth, getWidth()-outerRingWidth, getHeight()-outerRingWidth);
canvas.drawArc(rectF, startAngle, totalAngle, false, ringPaint);
//绘制内圆环
ringPaint.setStrokeWidth(innerRingWidth);
int padding = outerRingWidth + dp2px(getContext(), 12);
RectF innerRectF = new RectF(padding, padding, getWidth()-padding, getHeight()-padding);
canvas.drawArc(innerRectF, startAngle, totalAngle, false, ringPaint);
}
圆弧上总共有30个小刻度，遍历每隔小刻度，每个小刻度绘制较细的线，每3个刻度绘制一次文本，每6个刻度绘制一次较粗的线，通过旋转画布来实现，以使在同一位置绘制刻度和文本得以实现，最后要恢复画布。
private void drawDegreeScale(Canvas canvas) {
canvas.save();
int padding = dp2px(getContext(), 10);
canvas.rotate(-totalAngle/2, getWidth()/2, getHeight()/2); //将画布逆时间旋转一半弧度，使以左端点为刻度起点
for (int i=0;i<=totalDegreeScale;i++) {
ringPaint.setAlpha(80);
ringPaint.setStrokeWidth(2);
//每一格绘制一个浅色刻度
canvas.drawLine(getWidth()/2, padding, getWidth()/2, padding+innerRingWidth, ringPaint);
ringPaint.setAlpha(100);
ringPaint.setStrokeWidth(3);
//每6格刻度绘制一个深色刻度，即大刻度
if (i%6==0) {
canvas.drawLine(getWidth()/2, padding, getWidth()/2, padding+innerRingWidth+5, ringPaint);
}
//每三格刻度绘制一个文字
if (i%3==0) {
scoreTextPaint.setAlpha(180);
float textWidth = scoreTextPaint.measureText(scores[i/3]); //测量该文本宽度，需向左移动半个文本宽度以对齐
canvas.drawText(scores[i/3], getWidth()/2-textWidth/2, padding+innerRingWidth+dp2px(getContext(), 12), scoreTextPaint);
}
canvas.rotate(totalAngle/totalDegreeScale, getWidth()/2, getHeight()/2); //每次画完从中心开始旋转画布单位刻度的弧度
}
canvas.restore(); //恢复角度
}
绘制中心文本，包括beta，分数，信用评级，评估时间，这个很简单，就是需要获取文本的宽高调节依次垂直居中。
private void drawCenterText(Canvas canvas) {
//绘制当前分数
scoreTextPaint.setAlpha(255);
scoreTextPaint.setTextSize(170);
String curScore = String.valueOf(score);
Rect scoreRect = new Rect();
scoreTextPaint.getTextBounds(curScore, 0, curScore.length(), scoreRect); //需左移文字宽度以居中
canvas.drawText(curScore, getWidth()/2-scoreRect.width()/2, getHeight()/2, scoreTextPaint);
//绘制BETA文字
scoreTextPaint.setAlpha(150);
scoreTextPaint.setTextSize(35);
Rect betaRect= new Rect();
String betaStr = "BETA";
scoreTextPaint.getTextBounds(betaStr, 0, betaStr.length(), betaRect); //beta需向坐上移动
canvas.drawText(betaStr, getWidth()/2-betaRect.width()/2, getHeight()/2-scoreRect.height()-betaRect.height()/2, scoreTextPaint);
//绘制信用等级文本
scoreTextPaint.setAlpha(200);
scoreTextPaint.setTextSize(75);
Rect creditRect = new Rect();
scoreTextPaint.getTextBounds(creditStr, 0, creditStr.length(), creditRect);
canvas.drawText(creditStr, getWidth()/2-creditRect.width()/2, getHeight()/2+scoreRect.height()/2+20, scoreTextPaint);
//绘制评估时间
scoreTextPaint.setAlpha(150);
scoreTextPaint.setTextSize(35);
float timeStrWidth = scoreTextPaint.measureText("评估时间：2020.07.27");
canvas.drawText("评估时间:2020.07.27", getWidth()/2-timeStrWidth/2, getHeight()/2+scoreRect.height()+10, scoreTextPaint);
}
绘制进度动画小圆点:根据属性curProgressAngle的值来绘制指示器小圆点，圆心为中心，小圆点轨迹为圆，由三角函数知识得到坐标轨迹方程。
同时，使用Paint的BlurMaskFilter实现小圆点高斯模糊发光效果，发光模式为Blur.SOLID，内外发光。
private void drawDot(Canvas canvas) {
scoreTextPaint.setAlpha(230);
float x = (float) (getWidth()/2 + (getWidth()/2-outerRingWidth)*Math.sin(Math.toRadians(curProgressAngle)));
float y = (float) (getHeight()/2 - (getWidth()/2-outerRingWidth)*Math.cos(Math.toRadians(curProgressAngle)));
canvas.drawCircle(x, y, outerRingWidth, dotPaint);
}
使用ValueAnimator动画实时更新curProgressAngle并重绘，以实现小圆点实时更新位置实现进度动画。
private void startIndicatorAnim() {
ValueAnimator valueAnimator = ValueAnimator.ofFloat(-105, stopAngle);
valueAnimator.setDuration(ANIM_DURATION);
valueAnimator.setInterpolator(new AccelerateDecelerateInterpolator());
valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
curProgressAngle = (float) animation.getAnimatedValue();
postInvalidate(); //数值改变实时更新绘制
}
});
valueAnimator.start();
}
根据分数计算小圆点结束时的实际角度：在当前大刻度范围的结束角度，为之前刻度角度加上在该区间按比例得出的角度，30个小刻度共210°，每个小刻度perLevelAngle角度为7°
private String showCreditLevel() {
int startAngle = -105;
int perLevelAngle = totalAngle/5; //有5段大刻度
String creditLevelStr = null;
if (score < 350) {
creditLevelStr = "信用较差";
stopAngle = startAngle;
} else if (score >= 350 && score < 550) {
creditLevelStr = "信用较差";
stopAngle = startAngle + (float)(score-350)/(550-350)*perLevelAngle;
} else if (score >= 550 && score < 600) {
creditLevelStr = "信用中等";
stopAngle = startAngle + perLevelAngle + (float)(score-550)/(600-550)*perLevelAngle;
} else if (score >= 600 && score < 650) {
creditLevelStr = "信用良好";
stopAngle = startAngle + perLevelAngle*2 + (float)(score-600)/(650-600)*perLevelAngle;
} else if (score >= 650 && score < 700) {
creditLevelStr = "信用优秀";
stopAngle = startAngle + perLevelAngle*3 + (float)(score-650)/(700-650)*perLevelAngle;
} else if (score >= 700 && score < 950) {
creditLevelStr = "信用极好";
stopAngle = startAngle + perLevelAngle*4 + (float)(score-700)/(950-700)*perLevelAngle;
}
return creditLevelStr;
}
最后，通过ObjectAnimator实时更新分数。
public void runWithAnimation(int number){
ObjectAnimator objectAnimator = ObjectAnimator.ofInt(this, "score", 0, number);
objectAnimator.setDuration(ANIM_DURATION);
objectAnimator.setInterpolator(new AccelerateDecelerateInterpolator());
objectAnimator.start();
}
最后附上完整代码，喜欢的给个❤️吧。
/**
* create by libo
* create on 2020/7/27
* description 支付宝芝麻信用自定义view
*/
public class SesameCreditView extends View {
/** 圆环paint */
private Paint ringPaint;
/** 信用分文字paint */
private Paint scoreTextPaint;
/** 指示器paint */
private Paint dotPaint;
/** 外圆环宽度 */
private int outerRingWidth;
/** 内圆环宽度 */
private int innerRingWidth;
/** 表盘圆环总度数 */
private final int totalAngle = 210;
/** 圆弧上总共刻度数 */
private final int totalDegreeScale = 30;
/** 各分数刻度文本 */
private String[] scores = new String[] {"350", "较差", "550", "中等", "600", "良好", "650", "优秀", "700", "极好", "950"};
/** 信用分数 */
private int score = 715;
/** 当前扫过的数值角度 */
private float curProgressAngle;
/** 动画时长 */
private final long ANIM_DURATION = 2000;
/** 指示器结束时的角度 */
private float stopAngle;
/** 信用评级文字 */
private String creditStr;
public SesameCreditView(Context context) {
super(context);
init();
}
public SesameCreditView(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
init();
}
private void init() {
outerRingWidth = dp2px(getContext(), 3);
innerRingWidth = dp2px(getContext(), 10);
ringPaint = new Paint();
ringPaint.setColor(getResources().getColor(R.color.white));
ringPaint.setAntiAlias(true);
ringPaint.setStyle(Paint.Style.STROKE);
scoreTextPaint = new Paint();
scoreTextPaint.setColor(getResources().getColor(R.color.white));
scoreTextPaint.setAntiAlias(true);
scoreTextPaint.setTextSize(32);
dotPaint = new Paint();
dotPaint.setColor(getResources().getColor(R.color.white));
dotPaint.setAntiAlias(true);
dotPaint.setMaskFilter(new BlurMaskFilter(outerRingWidth, BlurMaskFilter.Blur.SOLID)); //设置指示器发光
creditStr = showCreditLevel();
startIndicatorAnim();
runWithAnimation(score);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
drawRing(canvas);
drawDegreeScale(canvas);
drawCenterText(canvas);
drawDot(canvas);
}
/**
* 绘制圆弧
* @param canvas
*/
private void drawRing (Canvas canvas) {
ringPaint.setAlpha(80);
int startAngle = -90-totalAngle/2; //圆环起始角度，12点钟位置为-90°
//绘制外圆环
ringPaint.setStrokeWidth(outerRingWidth);
RectF rectF = new RectF(outerRingWidth, outerRingWidth, getWidth()-outerRingWidth, getHeight()-outerRingWidth);
canvas.drawArc(rectF, startAngle, totalAngle, false, ringPaint);
//绘制内圆环
ringPaint.setStrokeWidth(innerRingWidth);
int padding = outerRingWidth + dp2px(getContext(), 12);
RectF innerRectF = new RectF(padding, padding, getWidth()-padding, getHeight()-padding);
canvas.drawArc(innerRectF, startAngle, totalAngle, false, ringPaint);
}
/**
* 绘制圆环刻度，分数文字
*/
private void drawDegreeScale(Canvas canvas) {
canvas.save();
int padding = dp2px(getContext(), 10);
canvas.rotate(-totalAngle/2, getWidth()/2, getHeight()/2); //将画布逆时间旋转一半弧度，使以左端点为刻度起点
for (int i=0;i<=totalDegreeScale;i++) {
ringPaint.setAlpha(80);
ringPaint.setStrokeWidth(2);
//每一格绘制一个浅色刻度
canvas.drawLine(getWidth()/2, padding, getWidth()/2, padding+innerRingWidth, ringPaint);
ringPaint.setAlpha(100);
ringPaint.setStrokeWidth(3);
//每6格刻度绘制一个深色刻度，即大刻度
if (i%6==0) {
canvas.drawLine(getWidth()/2, padding, getWidth()/2, padding+innerRingWidth+5, ringPaint);
}
//每三格刻度绘制一个文字
if (i%3==0) {
scoreTextPaint.setAlpha(180);
float textWidth = scoreTextPaint.measureText(scores[i/3]); //测量该文本宽度，需向左移动半个文本宽度以对齐
canvas.drawText(scores[i/3], getWidth()/2-textWidth/2, padding+innerRingWidth+dp2px(getContext(), 12), scoreTextPaint);
}
canvas.rotate(totalAngle/totalDegreeScale, getWidth()/2, getHeight()/2); //每次画完从中心开始旋转画布单位刻度的弧度
}
canvas.restore(); //恢复角度
}
/**
* 绘制中心文本
*/
private void drawCenterText(Canvas canvas) {
//绘制当前分数
scoreTextPaint.setAlpha(255);
scoreTextPaint.setTextSize(170);
String curScore = String.valueOf(score);
Rect scoreRect = new Rect();
scoreTextPaint.getTextBounds(curScore, 0, curScore.length(), scoreRect); //需左移文字宽度以居中
canvas.drawText(curScore, getWidth()/2-scoreRect.width()/2, getHeight()/2, scoreTextPaint);
//绘制BETA文字
scoreTextPaint.setAlpha(150);
scoreTextPaint.setTextSize(35);
Rect betaRect= new Rect();
String betaStr = "BETA";
scoreTextPaint.getTextBounds(betaStr, 0, betaStr.length(), betaRect); //beta需向坐上移动
canvas.drawText(betaStr, getWidth()/2-betaRect.width()/2, getHeight()/2-scoreRect.height()-betaRect.height()/2, scoreTextPaint);
//绘制信用等级文本
scoreTextPaint.setAlpha(200);
scoreTextPaint.setTextSize(75);
Rect creditRect = new Rect();
scoreTextPaint.getTextBounds(creditStr, 0, creditStr.length(), creditRect);
canvas.drawText(creditStr, getWidth()/2-creditRect.width()/2, getHeight()/2+scoreRect.height()/2+20, scoreTextPaint);
//绘制评估时间
scoreTextPaint.setAlpha(150);
scoreTextPaint.setTextSize(35);
float timeStrWidth = scoreTextPaint.measureText("评估时间：2020.07.27");
canvas.drawText("评估时间:2020.07.27", getWidth()/2-timeStrWidth/2, getHeight()/2+scoreRect.height()+10, scoreTextPaint);
}
/**
* 绘制进度动画小圆点
*/
private void drawDot(Canvas canvas) {
scoreTextPaint.setAlpha(230);
float x = (float) (getWidth()/2 + (getWidth()/2-outerRingWidth)*Math.sin(Math.toRadians(curProgressAngle)));
float y = (float) (getHeight()/2 - (getWidth()/2-outerRingWidth)*Math.cos(Math.toRadians(curProgressAngle)));
canvas.drawCircle(x, y, outerRingWidth, dotPaint);
}
/**
* 启动指示器加载动画
*/
private void startIndicatorAnim() {
ValueAnimator valueAnimator = ValueAnimator.ofFloat(-105, stopAngle);
valueAnimator.setDuration(ANIM_DURATION);
valueAnimator.setInterpolator(new AccelerateDecelerateInterpolator());
valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
curProgressAngle = (float) animation.getAnimatedValue();
postInvalidate(); //数值改变实时更新绘制
}
});
valueAnimator.start();
}
/**
* 设置信用水平，每一刻小刻度是7°
* 在当前大刻度范围的结束角度，为之前刻度角度加上在该区间按比例得出的角度
*/
private String showCreditLevel() {
int startAngle = -105;
int perLevelAngle = totalAngle/5; //有5段大刻度
String creditLevelStr = null;
if (score < 350) {
creditLevelStr = "信用较差";
stopAngle = startAngle;
} else if (score >= 350 && score < 550) {
creditLevelStr = "信用较差";
stopAngle = startAngle + (float)(score-350)/(550-350)*perLevelAngle;
} else if (score >= 550 && score < 600) {
creditLevelStr = "信用中等";
stopAngle = startAngle + perLevelAngle + (float)(score-550)/(600-550)*perLevelAngle;
} else if (score >= 600 && score < 650) {
creditLevelStr = "信用良好";
stopAngle = startAngle + perLevelAngle*2 + (float)(score-600)/(650-600)*perLevelAngle;
} else if (score >= 650 && score < 700) {
creditLevelStr = "信用优秀";
stopAngle = startAngle + perLevelAngle*3 + (float)(score-650)/(700-650)*perLevelAngle;
} else if (score >= 700 && score < 950) {
creditLevelStr = "信用极好";
stopAngle = startAngle + perLevelAngle*4 + (float)(score-700)/(950-700)*perLevelAngle;
}
return creditLevelStr;
}
public void runWithAnimation(int number){
ObjectAnimator objectAnimator = ObjectAnimator.ofInt(this, "score", 0, number);
objectAnimator.setDuration(ANIM_DURATION);
objectAnimator.setInterpolator(new AccelerateDecelerateInterpolator());
objectAnimator.start();
}
public int getScore() {
return score;
}
public void setScore(int score) {
this.score = score;
}
private int dp2px(Context context, float dp) {
final float scale = context.getResources().getDisplayMetrics().density;
return (int) (dp * scale + 0.5f);
}
}
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