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作者：红橙Darren

ArcView

实现效果

QQ截图20180323075921.png

package com.example.mylibrary.view;import android.content.Context;import android.content.res.TypedArray;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Rect;import android.graphics.RectF;import android.support.annotation.Nullable;import android.util.AttributeSet;import android.view.View;import com.example.mylibrary.R;/** * Created by renzhenming on 2018/3/22. * 圆弧形的进度条 */public class ArcView extends View{    private final Paint mBackgroundPaint;    private final Paint mForegroundPaint;    private final Paint mTextPaint;    //中间字体颜色    private int mCenterTextColor = Color.RED;    //中间字体大小    private int mCenterTextSize = 40;    //进度条宽度    private float mBorderWidth = 20;    //进度条已完成部分颜色    private int mForegroundColor = Color.RED;    //进度条进行中部分颜色    private int mBackgroundColor = Color.BLUE;    //总量和当前量    private float mTotalPercent = 0f;    private float mCurrentPercent = 0f;    public ArcView(Context context) {        this(context,null);    }    public ArcView(Context context, @Nullable AttributeSet attrs) {        this(context, attrs,-1);    }    public ArcView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {        super(context, attrs, defStyleAttr);        TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.ArcView);        mBackgroundColor = typedArray.getColor(R.styleable.ArcView_backgroundColor, mBackgroundColor);        mForegroundColor = typedArray.getColor(R.styleable.ArcView_foregroundColor, mForegroundColor);        mBorderWidth = typedArray.getDimension(R.styleable.ArcView_borderWidth,mBorderWidth);        mCenterTextSize = typedArray.getDimensionPixelSize(R.styleable.ArcView_centerTextSize,mCenterTextSize);        mCenterTextColor = typedArray.getColor(R.styleable.ArcView_centerTextColor,mCenterTextColor);        typedArray.recycle();        mBackgroundPaint = new Paint();        mBackgroundPaint.setAntiAlias(true);        mBackgroundPaint.setStrokeWidth(mBorderWidth);        mBackgroundPaint.setColor(mBackgroundColor);        //STROKE 画出来的圆弧不是封闭的，FILL是封闭的        mBackgroundPaint.setStyle(Paint.Style.STROKE);        mBackgroundPaint.setDither(true);        //Paint.Cap.ROUND设置圆弧首尾位置是ROUND的，不是直角        //Paint.Cap.SQUARE默认的是直角        mBackgroundPaint.setStrokeCap(Paint.Cap.ROUND);        mForegroundPaint = new Paint();        mForegroundPaint.setAntiAlias(true);        mForegroundPaint.setStrokeWidth(mBorderWidth);        mForegroundPaint.setDither(true);        mForegroundPaint.setColor(mForegroundColor);        //STROKE 画出来的圆弧不是封闭的，FILL是封闭的        mForegroundPaint.setStyle(Paint.Style.STROKE);        //Paint.Cap.ROUND设置圆弧首尾位置是ROUND的，不是直角        //Paint.Cap.SQUARE默认的是直角        mForegroundPaint.setStrokeCap(Paint.Cap.ROUND);        mTextPaint = new Paint();        mTextPaint.setAntiAlias(true);        mTextPaint.setDither(true);        mTextPaint.setColor(mCenterTextColor);        mTextPaint.setTextSize(mCenterTextSize);    }    @Override    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {        super.onMeasure(widthMeasureSpec, heightMeasureSpec);        //如果宽度和高度不一样，取最小值，确保是个正方形        int width = MeasureSpec.getSize(widthMeasureSpec);        int height = MeasureSpec.getSize(heightMeasureSpec);        setMeasuredDimension(width>height?height:width,width>height?height:width);    }    @Override    protected void onDraw(Canvas canvas) {        super.onDraw(canvas);        //画背景,        RectF rectF = new RectF(mBorderWidth / 2, mBorderWidth / 2, getWidth() - mBorderWidth / 2, getHeight() - mBorderWidth / 2);        //false表示圆弧不闭合,绘制的宽度也要占空间，所以RectF的设置上下左右要考虑去掉宽度的一般，猜测，        //绘制的时候是从边缘宽度的中心开始计算的        canvas.drawArc(rectF, 135, 270, false, mBackgroundPaint);        //画进行中的进度        if (mTotalPercent ==0 )return;        if ( mCurrentPercent > mTotalPercent){            mCurrentPercent = mTotalPercent;        }        float sweepAngle = mCurrentPercent/mTotalPercent;        canvas.drawArc(rectF,135,sweepAngle*270,false,mForegroundPaint);        //画文字        String s = ((int)mCurrentPercent) + "";        Rect bounds = new Rect();        mTextPaint.getTextBounds(s,0,s.length(),bounds);        //获取文字的起始位置，文字位于控件中间，所以起始位置等于控件宽度的        //一半减去文字宽度的一半        int start = getWidth()/2-bounds.width()/2;        Paint.FontMetrics metrics = mTextPaint.getFontMetrics();        //文字高度        //文字中心点距离底部的距离        int dy = (int) ((metrics.bottom-metrics.top)/2-metrics.bottom);        //获取基线baseline        int baseLine = getHeight()/2+dy;        canvas.drawText(s,start,baseLine,mTextPaint);    }    /**     * 设置总量     * @param totalProgress     */    public synchronized void setTotalProgress(int totalProgress){        this.mTotalPercent = totalProgress;    }    /**     * 设置当前量     * @param currentProgress     */    public synchronized void setCurrentProgress(int currentProgress){        this.mCurrentPercent = currentProgress;        invalidate();    }}

attrs

测试

public class TextCustomeViewActivity extends AppCompatActivity {    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_text_custormer_view);        final ArcView mArcView = (ArcView) findViewById(R.id.arcView);        mArcView.setTotalProgress(1000);        ValueAnimator animator = ValueAnimator.ofFloat(0,2000);        animator.setDuration(2000);        animator.start();        animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {            @Override            public void onAnimationUpdate(ValueAnimator animation) {                float currentProgress = (float) animation.getAnimatedValue();                mArcView.setCurrentProgress((int) currentProgress);            }        });    }}