Android自定义带动画的半圆环型进度效果

package com.newair.ondrawtext;

import android.animation.ValueAnimator;
import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.graphics.Typeface;
import android.os.Build;
import android.util.AttributeSet;
import android.view.View;
import android.view.animation.OvershootInterpolator;

/**
 * Created by ouhimehime on 16/6/15.
 * --------自定义控件-------
 */
public class CustomView extends View {


  //画笔
  private Paint paint;
  private RectF oval;


  //圆弧颜色
  private int roundColor;
  //进度颜色
  private int progressColor;
  //文字内容
  private boolean textIsShow;
  //字体大小
  private float textSize = 14;
  //文字颜色
  private int textColor;
  //最大进度
  private int max = 1000;
  //当前进度
  private int progress = 300;
  //圆弧宽度
  private int roundWidth = 30;

  private int viewWidth; //宽度--控件所占区域

  private float nowPro = 0;//用于动画

  private ValueAnimator animator;

  public CustomView(Context context) {
    super(context);
  }

  public CustomView(Context context, AttributeSet attrs) {
    super(context, attrs);
    initAttrs(attrs, context);
  }

  public CustomView(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
    initAttrs(attrs, context);
  }

  @TargetApi(Build.VERSION_CODES.LOLLIPOP)
  public CustomView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
    super(context, attrs, defStyleAttr, defStyleRes);
    initAttrs(attrs, context);
  }


  private void initAttrs(AttributeSet attr, Context context) {
    TypedArray array = context.obtainStyledAttributes(attr, R.styleable.CustomView);


    roundColor = array.getColor(R.styleable.CustomView_roundColor, Color.BLACK);//环形颜色
    progressColor = array.getColor(R.styleable.CustomView_progressColor, Color.RED);//进度颜色
    textIsShow = array.getBoolean(R.styleable.CustomView_textIsShow, false);//文字
    textSize = array.getDimension(R.styleable.CustomView_textSize, 14);//文字大小
    textColor = array.getColor(R.styleable.CustomView_textColor, Color.BLACK);//文字颜色
    roundWidth = array.getInt(R.styleable.CustomView_roundWidth, 30);//圆环宽度

    array.recycle();

    //动画
    animator = ValueAnimator.ofFloat(0, progress);
    animator.setDuration(1800);
    animator.setInterpolator(new OvershootInterpolator());
    animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
      @Override
      public void onAnimationUpdate(ValueAnimator animation) {
        nowPro = (float) animation.getAnimatedValue();
        postInvalidate();
      }
    });
    animator.start();

  }

  @Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

    final int widthSpecMode = MeasureSpec.getMode(widthMeasureSpec);
    final int widthSpecSize = MeasureSpec.getSize(widthMeasureSpec);

    if (widthSpecMode == MeasureSpec.AT_MOST) {//可获得最大空间
      setMeasuredDimension(widthMeasureSpec, (widthSpecSize / 2) + (int) (Math.cos(20) * (widthSpecSize / 2)));
    } else if (widthMeasureSpec == MeasureSpec.EXACTLY) {//一般指精确值
      setMeasuredDimension(widthMeasureSpec, (widthSpecSize / 2) + (int) (Math.cos(20) * (widthSpecSize / 2)));
    } else {
      setMeasuredDimension(widthMeasureSpec, (viewWidth / 2) + (int) (Math.cos(20) * (viewWidth / 2)));
    }
  }

  @Override
  protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    super.onSizeChanged(w, h, oldw, oldh);

    viewWidth = w;//得到宽度以此来计算控件所占实际大小

    //计算画布所占区域
    oval = new RectF();
    oval.left = roundWidth + getPaddingLeft();
    oval.top = roundWidth + getPaddingTop();
    oval.right = viewWidth - roundWidth - getPaddingRight();
    oval.bottom = viewWidth - roundWidth - getPaddingBottom();

  }


  @Override
  protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);

    Paint paint = new Paint();
    paint.setAntiAlias(true);            //设置画笔为无锯齿
    paint.setColor(roundColor);           //设置画笔颜色
    paint.setStrokeWidth(roundWidth);        //线宽
    paint.setStyle(Paint.Style.STROKE);       //空心
    canvas.drawArc(oval, 160, 220, false, paint);  //绘制圆弧

    //画进度层
    paint.setColor(progressColor);
    paint.setStrokeWidth(roundWidth + 1);
    canvas.drawArc(oval, 160, 220 * nowPro / max, false, paint); //绘制圆弧


    if (textIsShow) {
      paint.setColor(textColor);
      paint.setStrokeWidth(0);
      paint.setTypeface(Typeface.DEFAULT);
      paint.setTextSize(textSize * 2);
      float textWidth = paint.measureText((int) ((nowPro / (float) max) * 100) + "%");
      canvas.drawText((int) ((nowPro / (float) max) * 100) + "%", viewWidth / 2 - textWidth / 2, viewWidth / 2, paint);
    }

  }


  private int getDefaultHeight() {
    return 0;
  }

  private int getDefaultWidth() {
    return 0;
  }


  public int getRoundColor() {
    return roundColor;
  }

  public void setRoundColor(int roundColor) {
    this.roundColor = roundColor;
  }

  public int getProgressColor() {
    return progressColor;
  }

  public void setProgressColor(int progressColor) {
    this.progressColor = progressColor;
  }

  public boolean getText() {
    return textIsShow;
  }

  public void setText(boolean text) {
    this.textIsShow = text;
  }

  public float getTextSize() {
    return textSize;
  }

  public void setTextSize(float textSize) {
    this.textSize = textSize;
  }

  public int getTextColor() {
    return textColor;
  }

  public void setTextColor(int textColor) {
    this.textColor = textColor;
  }

  public int getMax() {
    return max;
  }

  public void setMax(int max) {
    this.max = max;
  }

  public int getProgress() {
    return progress;
  }

  public void setProgress(int progress) {
    this.progress = progress;
  }
}