用view 画出时钟表

爱被打了一巴掌 2022-07-16 12:40 169阅读 0赞

很有意思的一个小时钟，自动的。

clock

public class Clock extends View{
        
    
        private Paint circlePaint,dialPaint,numberPaint;
        //view 的宽高
        private float mWidth,mHeight;
        //圆的半径
        private float circleRadius;
        //圆心X,Y坐标
        private float circleX,circleY;
        private int second,minute;
        private double hour;
    
        private Handler handler = new Handler(Looper.getMainLooper()){
            @Override
            public void handleMessage(Message msg) {
                super.handleMessage(msg);
                if(msg.what==0){
                    invalidate();
                }
            }
        };
    
        public Clock(Context context, AttributeSet attrs) {
            super(context, attrs);
            initPaint();
        }
    
        private void initPaint(){
            //刻盘圆，小时刻度，时针和分针的画笔
            circlePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
            circlePaint.setColor(Color.BLACK);
            circlePaint.setStyle(Paint.Style.STROKE);
            circlePaint.setStrokeWidth(10);
    
            //分钟刻度的画笔
            dialPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
            dialPaint.setColor(Color.BLACK);
            dialPaint.setStrokeWidth(5);
    
            //数字的画笔
            numberPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
            numberPaint.setColor(Color.BLACK);
            numberPaint.setStrokeWidth(5);
            numberPaint.setTextSize(30);
        }
    
        @Override
        protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
            super.onMeasure(widthMeasureSpec, heightMeasureSpec);
            mWidth = getMeasuredWidth();
            mHeight = getMeasuredHeight();
            if(mWidth<mHeight){
                //圆的半径为view的宽度的一半再减9，防止贴边
                circleRadius = mWidth/2-9;
                circleX = mWidth/2;
                circleY = mHeight/2;
            } else{
                circleRadius = mHeight/2-9;
                circleX = mWidth/2;
                circleY = mHeight/2;
            }
        }
    
        @Override
        protected void onDraw(Canvas canvas) {
            super.onDraw(canvas);
            setTimes();
            drawCirclePoint(canvas);
            drawCircle(canvas);
            drawDial(canvas);
            drawPointer(canvas);
        }
    
        /**圆心
         * @param canvas
         */
        private void drawCirclePoint(Canvas canvas){
            canvas.drawCircle(circleX,circleY,5,circlePaint);
        }
    
        private void drawCircle(Canvas canvas){
            canvas.drawCircle(circleX,circleY,circleRadius,circlePaint);
        }
    
        /**画刻度及时间
         * @param canvas
         */
        private void drawDial(Canvas canvas){
            //时钟用长一点的刻度，画笔用画圆的画笔
            Point hourStartPoint = new Point(circleX,circleY-circleRadius);
            Point hourEndPoint = new Point(circleX,circleY-circleRadius+40);
            //分钟的刻度要稍微短一些，画笔用画圆的画笔
            Point startPoint2 = new Point(circleX,circleY-circleRadius);
            Point endPoint2 = new Point(circleX,circleY-circleRadius+10);
            //开始画刻度和数字，总共60个刻度，12个时钟刻度，被5整除画一个时钟刻度，被其余的为分针刻度
            String clockNumber;
            for(int i=0;i<60;i++){
                if(i%5==0){
                    if(i==0){
                        clockNumber = "12";
                    } else{
                        clockNumber = String.valueOf(i/5);
                    }
                    //时针刻度
                    canvas.drawLine(hourStartPoint.getX(),hourStartPoint.getY(),hourEndPoint.getX(),hourEndPoint.getY(),circlePaint);
                    //画数字，需在时针刻度末端加30
                    canvas.drawText(clockNumber,circleX-numberPaint.measureText(clockNumber)/2,hourEndPoint.getY()+30,numberPaint);
                } else{
                    //画分针刻度
                    canvas.drawLine(startPoint2.getX(),startPoint2.getY(),endPoint2.getX(),endPoint2.getY(),circlePaint);
                }
                //画布旋转6度
                canvas.rotate(360/60,circleX,circleY);
            }
        }
    
        /**画指针
         * X点坐标 cos(弧度)*r
         * Y点坐标 sin(弧度)*r
         * toRadians将角度转成弧度
         * 安卓坐标系与数学坐标系不同的地方是X轴是相反的，所以为了调整方向，需要将角度+270度
         * @param canvas
         */
        private void drawPointer(Canvas canvas){
            canvas.translate(circleX,circleY);
            float hourX = (float) Math.cos(Math.toRadians(hour*30+270))*circleRadius*0.5f;
            float hourY = (float) Math.sin(Math.toRadians(hour*30+270))*circleRadius*0.5f;
            float minuteX = (float) Math.cos(Math.toRadians(minute*6+270))*circleRadius*0.8f;
            float minuteY = (float) Math.sin(Math.toRadians(minute*6+270))*circleRadius*0.8f;
            float secondX = (float) Math.cos(Math.toRadians(second*6+270))*circleRadius*0.8f;
            float secondY = (float) Math.sin(Math.toRadians(second*6+270))*circleRadius*0.8f;
            canvas.drawLine(0,0,hourX,hourY,circlePaint);
            canvas.drawLine(0,0,minuteX,minuteY,circlePaint);
            canvas.drawLine(0,0,secondX,secondY,dialPaint);
            //一秒重绘一次
            handler.sendEmptyMessageDelayed(0,1000);
        }
    
        public void startClock(){
            setTimes();
            invalidate();
        }
    
        private void setTimes(){
            Date date = new Date();
            Calendar calendar = Calendar.getInstance();
            calendar.setTime(date);
            second = getTimes(date,Calendar.SECOND);
            minute = getTimes(date,Calendar.MINUTE);
            hour = getTimes(date,Calendar.HOUR)+minute/12*0.2;
        }
    
        private int getTimes(Date date,int calendarField){
            Calendar calendar = Calendar.getInstance();
            calendar.setTime(date);
            return calendar.get(calendarField);
        }
    
        public void stopClock(){
            handler.removeMessages(0);
        }
    
    }

point

public class Point {
    
        private float x; 
        private float y;
    
        public Point(float x, float y) {
            this.x = x;
            this.y = y;
        }
    
        public float getX() {
            return x;
        }
    
        public void setX(float x) {
            this.x = x;
        }
    
        public float getY() {
            return y;
        }
    
        public void setY(float y) {
            this.y = y;
        }
    }

这是在别人那里转来的，地址真不好意思的忘了。大家就看看吧。挺好看的

View 的布局不能忘记

<com.example.clockdrawer.ClockDraw 
                    android:layout_width="150dp"
                    android:layout_height="150dp"
                    android:id="@+id/clock_image"
                    android:layout_gravity="center_horizontal"
                    />