Android自定义圆环倒计时控件

本文实例为大家分享了Android自定义圆环倒计时控件的具体代码，供大家参考，具体内容如下

先来一张最终效果图:

主要思路: 在画渐变色圆环的时候,设置一个属性动画,根据属性动画的执行时长,来作为倒计时的时长.监听属性动画的进度,来达到 倒计时的目的.

二话不说,直接贴代码.具体实现思路都在注释上.

自定义属性:

<declare-styleable name="CountDownProgressBar">
 <attr name="countDown_circleWidth" format="dimension" />
 <attr name="countDown_centerTextSize" format="dimension" />
 <attr name="countDown_betaAngle" format="integer" />
 <attr name="countDown_firstColor" format="color" />
 <attr name="countDown_secondColor" format="color" />
 <attr name="countDown_centerTextColor" format="color" />
 <attr name="countDown_isShowGradient" format="boolean" />
</declare-styleable>

主要代码:

import android.animation.ValueAnimator;
import android.content.Context;
import android.content.res.Resources;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.LinearGradient;
import android.graphics.Paint;
import android.graphics.Paint.FontMetricsInt;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Shader;
import android.util.AttributeSet;
import android.util.TypedValue;
import android.view.View;
import android.view.animation.LinearInterpolator;

import com.daodaojk.myapplication.R;

public class CountDownProgressBar extends View {
/**
 * 进度条最大值
 */
private int maxValue = 200;

/**
 * 当前进度值
 */
private int currentValue ;

/**
 * 每次扫过的角度，用来设置进度条圆弧所对应的圆心角，alphaAngle=(currentValue/maxValue)*360
 */
private float alphaAngle;

/**
 * 底部圆弧的颜色，默认为Color.LTGRAY
 */
private int firstColor;

/**
 * 进度条圆弧块的颜色
 */
private int secondColor;
/**
 * 中间文字颜色(默认蓝色)
 */
private int centerTextColor = Color.BLUE;
/**
 * 中间文字的字体大小(默认40dp)
 */
private int centerTextSize;

/**
 * 圆环的宽度
 */
private int circleWidth;

/**
 * 画圆弧的画笔
 */
private Paint circlePaint;

/**
 * 画文字的画笔
 */
private Paint textPaint;
/**
 * 是否使用渐变色
 */
private boolean isShowGradient = false;

/**
 * 渐变圆周颜色数组
 */
private int[] colorArray = new int[]{Color.parseColor("#2773FF"),
  Color.parseColor("#27C0D2"), Color.parseColor("#40C66E")};
private int duration;
private OnFinishListener listener;
private ValueAnimator animator;

public CountDownProgressBar(Context context) {
 this(context, null);
}

public CountDownProgressBar(Context context, AttributeSet attrs) {
 this(context, attrs, 0);
}

public CountDownProgressBar(Context context, AttributeSet attrs, int defStyleAttr) {
 super(context, attrs, defStyleAttr);

TypedArray ta = context.getTheme().obtainStyledAttributes(attrs, R.styleable.CountDownProgressBar,
   defStyleAttr, 0);
 int n = ta.getIndexCount();

for (int i = 0; i < n; i++) {
  int attr = ta.getIndex(i);
  switch (attr) {
   case R.styleable.CountDownProgressBar_countDown_firstColor:
    firstColor = ta.getColor(attr, Color.LTGRAY); // 默认底色为亮灰色
    break;
   case R.styleable.CountDownProgressBar_countDown_secondColor:
    secondColor = ta.getColor(attr, Color.BLUE); // 默认进度条颜色为蓝色
    break;
   case R.styleable.CountDownProgressBar_countDown_centerTextSize:
    centerTextSize = ta.getDimensionPixelSize(attr, (int) dip2px(40)); // 默认中间文字字体大小为40dp
    break;
   case R.styleable.CountDownProgressBar_countDown_circleWidth:
    circleWidth = ta.getDimensionPixelSize(attr, (int) dip2px(6f)); // 默认圆弧宽度为6dp
    break;
   case R.styleable.CountDownProgressBar_countDown_centerTextColor:
    centerTextColor = ta.getColor(attr, Color.BLUE); // 默认中间文字颜色为蓝色
    break;
   case R.styleable.CountDownProgressBar_countDown_isShowGradient:
    isShowGradient = ta.getBoolean(attr, false); // 默认不适用渐变色
    break;
   default:
    break;
  }
 }
 ta.recycle();

circlePaint = new Paint();
 circlePaint.setAntiAlias(true); // 抗锯齿
 circlePaint.setDither(true); // 防抖动
 circlePaint.setStrokeWidth(circleWidth);//画笔宽度

textPaint = new Paint();
 textPaint.setAntiAlias(true);
 textPaint.setDither(true);
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
 // 分别获取期望的宽度和高度，并取其中较小的尺寸作为该控件的宽和高,并且不超过屏幕宽高
 int widthPixels = this.getResources().getDisplayMetrics().widthPixels;//获取屏幕宽
 int heightPixels = this.getResources().getDisplayMetrics().heightPixels;//获取屏幕高
 int width = MeasureSpec.getSize(widthMeasureSpec);
 int hedight = MeasureSpec.getSize(heightMeasureSpec);
 int minWidth = Math.min(widthPixels, width);
 int minHedight = Math.min(heightPixels, hedight);
 setMeasuredDimension(Math.min(minWidth, minHedight), Math.min(minWidth, minHedight));
}

@Override
protected void onDraw(Canvas canvas) {
 int center = this.getWidth() / 2;
 int radius = center - circleWidth / 2;

drawCircle(canvas, center, radius); // 绘制进度圆弧
 drawText(canvas, center);
}

/**
 * 绘制进度圆弧
 *
 * @param canvas 画布对象
 * @param center 圆心的x和y坐标
 * @param radius 圆的半径
 */
private void drawCircle(Canvas canvas, int center, int radius) {
 circlePaint.setShader(null); // 清除上一次的shader
 circlePaint.setColor(firstColor); // 设置底部圆环的颜色，这里使用第一种颜色
 circlePaint.setStyle(Paint.Style.STROKE); // 设置绘制的圆为空心
 canvas.drawCircle(center, center, radius, circlePaint); // 画底部的空心圆
 RectF oval = new RectF(center - radius, center - radius, center + radius, center + radius); // 圆的外接正方形
 if (isShowGradient) {
  // 绘制颜色渐变圆环
  // shader类是Android在图形变换中非常重要的一个类。Shader在三维软件中我们称之为着色器，其作用是来给图像着色。
  LinearGradient linearGradient = new LinearGradient(circleWidth, circleWidth, getMeasuredWidth()
    - circleWidth, getMeasuredHeight() - circleWidth, colorArray, null, Shader.TileMode.MIRROR);
  circlePaint.setShader(linearGradient);
 }
 circlePaint.setShadowLayer(10, 10, 10, Color.BLUE);
 circlePaint.setColor(secondColor); // 设置圆弧的颜色
 circlePaint.setStrokeCap(Paint.Cap.ROUND); // 把每段圆弧改成圆角的

alphaAngle = currentValue * 360.0f / maxValue * 1.0f; // 计算每次画圆弧时扫过的角度，这里计算要注意分母要转为float类型，否则alphaAngle永远为0
 canvas.drawArc(oval, -90, alphaAngle, false, circlePaint);
}

/**
 * 绘制文字
 *
 * @param canvas 画布对象
 * @param center 圆心的x和y坐标
 */
private void drawText(Canvas canvas, int center) {
 int result = ((maxValue - currentValue) * (duration / 1000) / maxValue); // 计算进度
 String percent;
 if (maxValue == currentValue) {
  percent = "完成";
  textPaint.setTextSize(centerTextSize); // 设置要绘制的文字大小
 } else {
  percent = (result / 60 < 10 ? "0" + result / 60 : result / 60) + ":" + (result ％ 60 < 10 ? "0" + result ％ 60 : result ％ 60);
//   percent = result+"秒";
  textPaint.setTextSize(centerTextSize+centerTextSize/3); // 设置要绘制的文字大小
 }
 textPaint.setTextAlign(Paint.Align.CENTER); // 设置文字居中，文字的x坐标要注意
 textPaint.setColor(centerTextColor); // 设置文字颜色

textPaint.setStrokeWidth(0); // 注意此处一定要重新设置宽度为0,否则绘制的文字会重叠
 Rect bounds = new Rect(); // 文字边框
 textPaint.getTextBounds(percent, 0, percent.length(), bounds); // 获得绘制文字的边界矩形
 FontMetricsInt fontMetrics = textPaint.getFontMetricsInt(); // 获取绘制Text时的四条线
 int baseline = center + (fontMetrics.bottom - fontMetrics.top) / 2 - fontMetrics.bottom; // 计算文字的基线  canvas.drawText(percent, center, baseline, textPaint); // 绘制表示进度的文字

}

/**
 * 设置圆环的宽度
 *
 * @param width
 */
public void setCircleWidth(int width) {
 this.circleWidth = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, width, getResources()
   .getDisplayMetrics());
 circlePaint.setStrokeWidth(circleWidth);
 //一般只是希望在View发生改变时对UI进行重绘。invalidate()方法系统会自动调用 View的onDraw()方法。
 invalidate();
}

/**
 * 设置圆环的底色，默认为亮灰色LTGRAY
 *
 * @param color
 */
public void setFirstColor(int color) {
 this.firstColor = color;
 circlePaint.setColor(firstColor);
 //一般只是希望在View发生改变时对UI进行重绘。invalidate()方法系统会自动调用 View的onDraw()方法。
 invalidate();
}

/**
 * 设置进度条的颜色，默认为蓝色<br>
 *
 * @param color
 */
public void setSecondColor(int color) {
 this.secondColor = color;
 circlePaint.setColor(secondColor);
 //一般只是希望在View发生改变时对UI进行重绘。invalidate()方法系统会自动调用 View的onDraw()方法。
 invalidate();
}

/**
 * 设置进度条渐变色颜色数组
 *
 * @param colors 颜色数组，类型为int[]
 */
public void setColorArray(int[] colors) {
 this.colorArray = colors;
 //一般只是希望在View发生改变时对UI进行重绘。invalidate()方法系统会自动调用 View的onDraw()方法。
 invalidate();
}

/**
 * 按进度显示百分比，可选择是否启用数字动画
 *
 * @param duration 动画时长
 */
public void setDuration(int duration, OnFinishListener listener) {
  this.listener = listener;
 this.duration = duration + 1000;
 if (animator != null) {
  animator.cancel();
 } else {
  animator = ValueAnimator.ofInt(0, maxValue);
  animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
   @Override
   public void onAnimationUpdate(ValueAnimator animation) {
    currentValue = (int) animation.getAnimatedValue();
    //一般只是希望在View发生改变时对UI进行重绘。invalidate()方法系统会自动调用 View的onDraw()方法。
    invalidate();
    if (maxValue == currentValue && CountDownProgressBar.this.listener != null) {
     CountDownProgressBar.this.listener.onFinish();
    }
   }
  });
  animator.setInterpolator(new LinearInterpolator());
 }
 animator.setDuration(duration);
 animator.start();
}

public interface OnFinishListener {
 void onFinish();
}

public void setOnFinishListener(OnFinishListener listener) {
 this.listener = listener;
}

public static int px2dip(int pxValue) {
 final float scale = Resources.getSystem().getDisplayMetrics().density;
 return (int) (pxValue / scale + 0.5f);
}

public static float dip2px(float dipValue) {
 final float scale = Resources.getSystem().getDisplayMetrics().density;
 return (dipValue * scale + 0.5f);
}
}

xml布局:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical">
<Button
android:layout_width="match_parent"
android:text="开始"
android:id="@+id/btn_start"
android:layout_height="wrap_content" />
<com.daodaojk.myapplication.view.CountDownProgressBar
 android:id="@+id/cpb_countdown"
 android:layout_width="200dp"
 android:layout_marginTop="100dp"
 android:layout_gravity="center_horizontal"
 app:countDown_centerTextSize="25dp"
 app:countDown_circleWidth="4dp"
 app:countDown_firstColor="@color/text_gray_ccc"
 app:countDown_secondColor="@color/text_blue"
 app:countDown_isShowGradient="true"
 app:countDown_centerTextColor="#2395FF"
 android:layout_height="200dp" />
</LinearLayout>

页面调用:

package com.daodaojk.myapplication.ui;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import com.daodaojk.myapplication.R;
import com.daodaojk.myapplication.view.CountDownProgressBar;

public class CountDownActivity extends AppCompatActivity {

private CountDownProgressBar cpb_countdown;

@Override
protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_count_down);
 Button btn_start = findViewById(R.id.btn_start);
 cpb_countdown = (CountDownProgressBar) findViewById(R.id.cpb_countdown);
 btn_start.setOnClickListener(new View.OnClickListener() {
  @Override
  public void onClick(View v) {
   cpb_countdown.setDuration(10000, new CountDownProgressBar.OnFinishListener() {
    @Override
    public void onFinish() {
     Toast.makeText(CountDownActivity.this, "完成了", Toast.LENGTH_SHORT).show();
    }
   });
  }
 });
}
}

来源：https://blog.csdn.net/baidu_36619149/article/details/80163745