我开发的应用程序和放大器;刚刚建成的逻辑部分。现在，我要设计这个程序就像在著名的定时器apps.for的例子：

I am developing an app & just built its logical part. Now I want to design this app like in famous timer apps.for examples:

我想要的东西是外圆，随着某些事件或增加数量的每一个触发罢了。其实我不知道这是它的动画部分（喜欢被内置闪光灯或者是什么），通过使用其内置的属性和功能的机器人本身的编码，或只是可能。 所以，如果有人告诉我解释什么工具使用或任何参考教程，可以从底部解释的事情。我真的不知道设计的任何东西。任何code本??

The thing I want is the outer Circle that fills with every trigger of some event or with increment of number. I actually don't know that is it animation part (like to be built in flash or what) or just possible by coding in android itself using its inbuilt properties and features. So anybody if tell explain me what tools are used or any reference tutorial that can explain things from bottom. I really don't know any thing of designing . Any code for this??

推荐答案

请问这该怎么办？

更新：的现在还正确处理现实世界的时间

Update: Now also correctly handles real world time.

样品截图：

Sample Screenshot:

code：

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.text.TextPaint;
import android.view.View;

import android.graphics.*;


public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(new CircularCountdown(this));
    }

    private static class CircularCountdown extends View {

        private final Paint backgroundPaint;
        private final Paint progressPaint;
        private final Paint textPaint;

        private long startTime;
        private long currentTime;
        private long maxTime;

        private long progressMillisecond;
        private double progress;

        private RectF circleBounds;
        private float radius;
        private float handleRadius;
        private float textHeight;
        private float textOffset;

        private final Handler viewHandler;
        private final Runnable updateView;

        public CircularCountdown(Context context) {
            super(context);

            // used to fit the circle into
            circleBounds = new RectF();

            // size of circle and handle
            radius = 200;
            handleRadius = 10;

            // limit the counter to go up to maxTime ms
            maxTime = 5000;

            // start and current time
            startTime = System.currentTimeMillis();
            currentTime = startTime;


            // the style of the background
            backgroundPaint = new Paint();
            backgroundPaint.setStyle(Paint.Style.STROKE);
            backgroundPaint.setAntiAlias(true);
            backgroundPaint.setStrokeWidth(10);
            backgroundPaint.setStrokeCap(Paint.Cap.SQUARE);
            backgroundPaint.setColor(Color.parseColor("#4D4D4D"));  // dark gray

            // the style of the 'progress'
            progressPaint = new Paint();
            progressPaint.setStyle(Paint.Style.STROKE);
            progressPaint.setAntiAlias(true);
            progressPaint.setStrokeWidth(10);
            progressPaint.setStrokeCap(Paint.Cap.SQUARE);
            progressPaint.setColor(Color.parseColor("#00A9FF"));    // light blue

            // the style for the text in the middle
            textPaint = new TextPaint();
            textPaint.setTextSize(radius / 2);
            textPaint.setColor(Color.BLACK);
            textPaint.setTextAlign(Paint.Align.CENTER);

            // text attributes
            textHeight = textPaint.descent() - textPaint.ascent();
            textOffset = (textHeight / 2) - textPaint.descent();


            // This will ensure the animation will run periodically
            viewHandler = new Handler();
            updateView = new Runnable(){
                @Override
                public void run(){
                    // update current time
                    currentTime = System.currentTimeMillis();

                    // get elapsed time in milliseconds and clamp between <0, maxTime>
                    progressMillisecond = (currentTime - startTime) % maxTime;

                    // get current progress on a range <0, 1>
                    progress = (double) progressMillisecond / maxTime;

                    CircularCountdown.this.invalidate();
                    viewHandler.postDelayed(updateView, 1000/60);
                }
            };
            viewHandler.post(updateView);
        }



        @Override
        protected void onDraw(Canvas canvas) {
            super.onDraw(canvas);

            // get the center of the view
            float centerWidth = canvas.getWidth() / 2;
            float centerHeight = canvas.getHeight() / 2;


            // set bound of our circle in the middle of the view
            circleBounds.set(centerWidth - radius,
                    centerHeight - radius,
                    centerWidth + radius,
                    centerHeight + radius);


            // draw background circle
            canvas.drawCircle(centerWidth, centerHeight, radius, backgroundPaint);

            // we want to start at -90°, 0° is pointing to the right
            canvas.drawArc(circleBounds, -90, (float)(progress*360), false, progressPaint);

            // display text inside the circle
            canvas.drawText((double)(progressMillisecond/100)/10 + "s",
                            centerWidth,
                            centerHeight + textOffset,
                            textPaint);

            // draw handle or the circle
            canvas.drawCircle((float)(centerWidth  + (Math.sin(progress * 2 * Math.PI) * radius)),
                              (float)(centerHeight - (Math.cos(progress * 2 * Math.PI) * radius)),
                              handleRadius,
                              progressPaint);
        }

    }

}