Android Custom Ring Progress Bar

Android custom ring progress bar for your reference, the specific content is as follows

The requirement is to realize a circular progress bar with progress in the middle, and realize one by yourself

package com.djt.aienglish.widget;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.RectF;
import android.text.TextUtils;
import android.util.AttributeSet;
import android.view.View;

import com.djt.aienglish.R;


/**
 * @author qiu
 * @date 2020/3/12 13:51
 */
public class CirclePgBar extends View {
    private int mHeight = 0;
    private int mWidth = 0;

    //  A brush for drawing rings 
    private Paint mRingPaint;
    //  Brush background color for drawing rings 
    private Paint mRingPaintBg;
    //  A brush for drawing fonts 
    private Paint mTextPaint;
    //  Ring color 
    private int mRingColor;
    //  Ring background color 
    private int mRingBgColor;
    //  Radius 
    private float mRadius;
    //  Ring radius 
    private float mRingRadius;
    //  Ring width 
    private float mStrokeWidth;
    //  Center of Circle x Coordinates 
    private int mXCenter;
    //  Center of Circle y Coordinates 
    private int mYCenter;
    //  The length of a word 
    private float mTxtWidth;
    //  Height of words 
    private float mTxtHeight;
    //  Total progress 
    private int max = 100;
    //  Current progress 
    private int progress;
    private String text;

    public CirclePgBar(Context context, AttributeSet attrs) {
        super(context, attrs);
        //  Get custom properties 
        initAttrs(context, attrs);
        initVariable();
    }

    /**
     *  Attribute 
     */
    private void initAttrs(Context context, AttributeSet attrs) {
        TypedArray typeArray = context.getTheme().obtainStyledAttributes(attrs,
                R.styleable.TasksCompletedView, 0, 0);
        mStrokeWidth = typeArray.getDimension(R.styleable.TasksCompletedView_circleWidth, 0);
        mRingColor = typeArray.getColor(R.styleable.TasksCompletedView_ringColor, 0xFFFFFFFF);
        mRingBgColor = typeArray.getColor(R.styleable.TasksCompletedView_ringBgColor, 0xFFFFFFFF);
        text = typeArray.getString(R.styleable.TasksCompletedView_text);
        max = typeArray.getInteger(R.styleable.TasksCompletedView_max, 0);
        progress = typeArray.getInteger(R.styleable.TasksCompletedView_progress, 0);
    }

    /**
     *  Initialize brush 
     */
    private void initVariable() {
        // Outer circular arc background 
        mRingPaintBg = new Paint();
        mRingPaintBg.setAntiAlias(true);
        mRingPaintBg.setColor(mRingBgColor);
        mRingPaintBg.setStyle(Paint.Style.STROKE);
        mRingPaintBg.setStrokeWidth(mStrokeWidth);
        // Outer arc 
        mRingPaint = new Paint();
        mRingPaint.setAntiAlias(true);
        mRingPaint.setColor(mRingColor);
        mRingPaint.setStyle(Paint.Style.STROKE);
        mRingPaint.setStrokeWidth(mStrokeWidth);
        //mRingPaint.setStrokeCap(Paint.Cap.ROUND);// Set the line emitting style, which has a circle   Be well-behaved 
        // Middle word 
        mTextPaint = new Paint();
        mTextPaint.setAntiAlias(true);
        mTextPaint.setStyle(Paint.Style.FILL);
        mTextPaint.setColor(mRingColor);
        invalidate();
    }

    // Measurement 
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        // Actual measured width and height 
        mHeight = getMeasuredHeight();
        mWidth = getMeasuredWidth();
        if (mWidth > mHeight) {
            mRadius = mHeight / 2;
        } else {
            mRadius = mWidth / 2;
        }
        // Radius 
        mRingRadius = mRadius - mStrokeWidth / 2;
        // Text width and height measurement 
        mTextPaint.setTextSize(mRadius / 2);
        Paint.FontMetrics fm = mTextPaint.getFontMetrics();
        mTxtHeight = (int) Math.ceil(fm.descent - fm.ascent);
    }

    /**
     *  Draw a picture 
     */
    @Override
    protected void onDraw(Canvas canvas) {
        mXCenter = mWidth / 2;
        mYCenter = mHeight / 2;
        // Outer circular arc background 
        RectF rectBg = new RectF(mXCenter - mRingRadius, mYCenter - mRingRadius, mXCenter + mRingRadius, mYCenter + mRingRadius);
        canvas.drawArc(rectBg, 0, 360, false, mRingPaintBg);
        // Outer arc // Progress 
        if (progress > 0) {
            RectF oval = new RectF(mXCenter - mRingRadius, mYCenter - mRingRadius, mXCenter + mRingRadius, mYCenter + mRingRadius);
            canvas.drawArc(oval, -90, ((float) progress / max) * 360, false, mRingPaint);
        }
        // Font 
        if(!TextUtils.isEmpty(text)) {
            mTxtWidth = mTextPaint.measureText(text, 0, text.length());
            canvas.drawText(text, mXCenter - mTxtWidth / 2, mYCenter + mTxtHeight / 4, mTextPaint);
        }
    }

    /**
     *  Setting progress 
     *
     * @param progress
     */
    public void setProgress(int progress) {
        this.progress = progress;
        postInvalidate();// Redraw 
    }

    /**
     *  Set the maximum value 
     *
     * @param max
     */
    public void setMax(int max) {
        this.max = max;
        postInvalidate();
    }

    /**
     *  Set text content 
     *
     * @param text
     */
    public void setText(String text) {
        this.text = text;
        postInvalidate();
    }
}

Don't forget to add the default configuration attribute in attr. xml under value

<!-- Arc progress bar -->
    <declare-styleable name="TasksCompletedView">
        <attr name="circleWidth" format="dimension" />
        <attr name="ringColor" format="color" />
        <attr name="ringBgColor" format="color" />
        <attr name="text" format="string" />
        <attr name="progress" format="integer" />
     <attr name="max" format="integer" />
</declare-styleable>