本文实例为大家分享了Android自定义View倒计时圆的具体代码，供大家参考，具体内容如下

创建attr

创建DisplayUtil 类

import android.content.Context;

/**

* Created by 王 on 2017/10/21.

*/

public class DisplayUtil {

/**

* 将px装换成dp，保证尺寸不变

* @param context

* @param pxValue

* @return

*/

public static int px2dp(Context context, float pxValue){

float density = context.getResources().getDisplayMetrics().density;//得到设备的密度

return (int) (pxValue/density+0.5f);

}

public static int dp2px(Context context,float dpValue){

float density = context.getResources().getDisplayMetrics().density;

return (int) (dpValue*density+0.5f);

}

public static int px2sp(Context context,float pxValue){

float scaleDensity = context.getResources().getDisplayMetrics().scaledDensity;//缩放密度

return (int) (pxValue/scaleDensity+0.5f);

}

public static int sp2px(Context context,float spValue) {

float scaleDensity = context.getResources().getDisplayMetrics().scaledDensity;

return (int) (spValue*scaleDensity+0.5f);

}

}

继承View

import android.animation.Animator;

import android.animation.AnimatorListenerAdapter;

import android.animation.ValueAnimator;

import android.content.Context;

import android.content.res.TypedArray;

import android.graphics.Canvas;

import android.graphics.Paint;

import android.graphics.RectF;

import android.util.AttributeSet;

import android.view.View;

import android.view.animation.LinearInterpolator;

/**

* Created by 王 on 2017/10/21.

*/

public class CountDownView extends View{

//圆轮颜色

private int mRingColor;

//圆轮宽度

private float mRingWidth;

//圆轮进度值文本大小

private int mRingProgessTextSize;

//宽度

private int mWidth;

//高度

private int mHeight;

private Paint mPaint;

//圆环的矩形区域

private RectF mRectF;

//

private int mProgessTextColor;

private int mCountdownTime;

private float mCurrentProgress;

private OnCountDownFinishListener mListener;

public CountDownView(Context context) {

this(context, null);

}

public CountDownView(Context context, AttributeSet attrs) {

this(context, attrs, 0);

}

public CountDownView(Context context, AttributeSet attrs, int defStyleAttr) {

super(context, attrs, defStyleAttr);

TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CountDownView);

mRingColor = a.getColor(R.styleable.CountDownView_ringColor, context.getResources().getColor(R.color.colorAccent));

mRingWidth = a.getFloat(R.styleable.CountDownView_ringWidth, 40);

mRingProgessTextSize = a.getDimensionPixelSize(R.styleable.CountDownView_progressTextSize, DisplayUtil.sp2px(context, 20));

mProgessTextColor = a.getColor(R.styleable.CountDownView_progressTextColor, context.getResources().getColor(R.color.colorAccent));

mCountdownTime = a.getInteger(R.styleable.CountDownView_countdownTime, 10);

a.recycle();

mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);

mPaint.setAntiAlias(true);

this.setWillNotDraw(false);

}

public void setCountdownTime(int mCountdownTime) {

this.mCountdownTime = mCountdownTime;

}

@Override

protected void onLayout(boolean changed, int left, int top, int right, int bottom) {

super.onLayout(changed, left, top, right, bottom);

mWidth = getMeasuredWidth();

mHeight = getMeasuredHeight();

mRectF = new RectF(0 + mRingWidth / 2, 0 + mRingWidth / 2,

mWidth - mRingWidth / 2, mHeight - mRingWidth / 2);

}

@Override

protected void onDraw(Canvas canvas) {

super.onDraw(canvas);

/**

*圆环

*/

//颜色

mPaint.setColor(mRingColor);

//空心

mPaint.setStyle(Paint.Style.STROKE);

//宽度

mPaint.setStrokeWidth(mRingWidth);

canvas.drawArc(mRectF, -90, mCurrentProgress - 360, false, mPaint);

//绘制文本

Paint textPaint = new Paint();

textPaint.setAntiAlias(true);

textPaint.setTextAlign(Paint.Align.CENTER);

String text = mCountdownTime - (int) (mCurrentProgress / 360f * mCountdownTime) + "";

textPaint.setTextSize(mRingProgessTextSize);

textPaint.setColor(mProgessTextColor);

//文字居中显示

Paint.FontMetricsInt fontMetrics = textPaint.getFontMetricsInt();

int baseline = (int) ((mRectF.bottom + mRectF.top - fontMetrics.bottom - fontMetrics.top) / 2);

canvas.drawText(text, mRectF.centerX(), baseline, textPaint);

}

private ValueAnimator getValA(long countdownTime) {

ValueAnimator valueAnimator = ValueAnimator.ofFloat(0, 100);

valueAnimator.setDuration(countdownTime);

valueAnimator.setInterpolator(new LinearInterpolator());

valueAnimator.setRepeatCount(0);

return valueAnimator;

}

/**

* 开始倒计时

*/

public void startCountDown() {

setClickable(false);

ValueAnimator valueAnimator = getValA(mCountdownTime * 1000);

valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {

@Override

public void onAnimationUpdate(ValueAnimator animation) {

float i = Float.valueOf(String.valueOf(animation.getAnimatedValue()));

mCurrentProgress = (int) (360 * (i / 100f));

invalidate();

}

});

valueAnimator.start();

valueAnimator.addListener(new AnimatorListenerAdapter() {

@Override

public void onAnimationEnd(Animator animation) {

super.onAnimationEnd(animation);

//倒计时结束回调

if (mListener != null) {

mListener.countDownFinished();

}

setClickable(true);

}

});

}

public void setAddCountDownListener(OnCountDownFinishListener mListener) {

this.mListener = mListener;

}

public interface OnCountDownFinishListener {

void countDownFinished();

}

}

布局

xmlns:app="http://schemas.android.com/apk/res-auto"

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

tools:context="com.example.circulardemo.MainActivity">

android:id="@+id/cdv"

android:layout_width="50dp"

android:layout_height="50dp"

android:layout_centerVertical="true"

android:layout_centerHorizontal="true" />

Mainactivity

import android.os.Bundle;

import android.support.v7.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

CountDownView countDownView = (CountDownView) findViewById(R.id.cdv);

//启动

countDownView.startCountDown();

countDownView.setAddCountDownListener(new CountDownView.OnCountDownFinishListener() {

@Override

public void countDownFinished() {

Toast.makeText(MainActivity.this, "倒计时结束", Toast.LENGTH_SHORT).show();

}

});

}

}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。