自定义View倒计时

1.创建一个类，继承Viewpublic class CompletedView extends View {    // 画实心圆的画笔    private Paint mCirclePaint;    // 画圆环的画笔    private Paint mRingPaint;    // 画圆环的画笔背景色    private Paint mRingPaintBg;    // 画字体的画笔    private Paint mTextPaint;    // 圆形颜色    private int mCircleColor;    // 圆环颜色    private int mRingColor;    // 圆环背景颜色    private int mRingBgColor;    // 半径    private float mRadius;    // 圆环半径    private float mRingRadius;    // 圆环宽度    private float mStrokeWidth;    // 圆心x坐标    private int mXCenter;    // 圆心y坐标    private int mYCenter;    // 字的长度    private float mTxtWidth;    // 字的高度    private float mTxtHeight;    // 总进度    private int mTotalProgress = 100;    // 当前进度    private int mProgress;    public CompletedView(Context context, AttributeSet attrs) {        super(context, attrs);        // 获取自定义的属性        initAttrs(context, attrs);        initVariable();    }    //属性    private void initAttrs(Context context, AttributeSet attrs) {        TypedArray typeArray = context.getTheme().obtainStyledAttributes(attrs,                R.styleable.TasksCompletedView, 0, 0);        mRadius = typeArray.getDimension(R.styleable.TasksCompletedView_radius, 80);        mStrokeWidth = typeArray.getDimension(R.styleable.TasksCompletedView_strokeWidth, 10);        mCircleColor = typeArray.getColor(R.styleable.TasksCompletedView_circleColor, 0xFFFFFFFF);        mRingColor = typeArray.getColor(R.styleable.TasksCompletedView_ringColor, 0xFFFFFFFF);        mRingBgColor = typeArray.getColor(R.styleable.TasksCompletedView_ringBgColor, 0xFFFFFFFF);        mRingRadius = mRadius + mStrokeWidth / 2;    }    //初始化画笔    private void initVariable() {        //内圆        mCirclePaint = new Paint();        mCirclePaint.setAntiAlias(true);        mCirclePaint.setColor(mCircleColor);        mCirclePaint.setStyle(Paint.Style.FILL);        //外圆弧背景        mRingPaintBg = new Paint();        mRingPaintBg.setAntiAlias(true);        mRingPaintBg.setColor(mRingBgColor);        mRingPaintBg.setStyle(Paint.Style.STROKE);        mRingPaintBg.setStrokeWidth(mStrokeWidth);        //外圆弧        mRingPaint = new Paint();        mRingPaint.setAntiAlias(true);        mRingPaint.setColor(mRingColor);        mRingPaint.setStyle(Paint.Style.STROKE);        mRingPaint.setStrokeWidth(mStrokeWidth);        //mRingPaint.setStrokeCap(Paint.Cap.ROUND);//设置线冒样式，有圆 有方        //中间字        mTextPaint = new Paint();        mTextPaint.setAntiAlias(true);        mTextPaint.setStyle(Paint.Style.FILL);        mTextPaint.setColor(mRingColor);        mTextPaint.setTextSize(mRadius / 2);        Paint.FontMetrics fm = mTextPaint.getFontMetrics();        mTxtHeight = (int) Math.ceil(fm.descent - fm.ascent);    }    //画图    @Override    protected void onDraw(Canvas canvas) {        mXCenter = getWidth() / 2;        mYCenter = getHeight() / 2;        //内圆        canvas.drawCircle(mXCenter, mYCenter, mRadius, mCirclePaint);        //外圆弧背景        RectF oval1 = new RectF();        oval1.left = (mXCenter - mRingRadius);        oval1.top = (mYCenter - mRingRadius);        oval1.right = mRingRadius * 2 + (mXCenter - mRingRadius);        oval1.bottom = mRingRadius * 2 + (mYCenter - mRingRadius);        canvas.drawArc(oval1, 0, 360, false, mRingPaintBg); //圆弧所在的椭圆对象、圆弧的起始角度、圆弧的角度、是否显示半径连线        //外圆弧        if (mProgress > 0 ) {            RectF oval = new RectF();            oval.left = (mXCenter - mRingRadius);            oval.top = (mYCenter - mRingRadius);            oval.right = mRingRadius * 2 + (mXCenter - mRingRadius);            oval.bottom = mRingRadius * 2 + (mYCenter - mRingRadius);            canvas.drawArc(oval, -90, ((float)mProgress / mTotalProgress) * 360, false, mRingPaint); //            //字体            String txt = mProgress+"";            mTxtWidth = mTextPaint.measureText(txt, 0, txt.length());            canvas.drawText(txt, mXCenter - mTxtWidth / 2, mYCenter + mTxtHeight / 4, mTextPaint);        }    }    //设置进度    public void setProgress(int progress) {        mProgress = progress;        postInvalidate();//重绘    }}2.创建自定义属性和颜色
<resources>    <!--圆弧进度条-->    <declare-styleable name="TasksCompletedView">        <attr name="radius" format="dimension"/>        <attr name="strokeWidth" format="dimension"/>        <attr name="circleColor" format="color"/>        <attr name="ringColor" format="color"/>        <attr name="ringBgColor" format="color"/>    </declare-styleable>
<color name="white">#FFFFFF</color><color name="white2">#f5f3f3</color><color name="colorRed">#d50f09</color>


3. 运用布局

主布局加入：xmlns:tc="http://schemas.android.com/apk/res-auto"
<com.bwie.test.zhoukao3.CompletedView    android:id="@+id/tasks_view"    android:layout_width="223dp"    android:layout_height="223dp"    tc:circleColor="@color/white"    tc:radius="50dip"    tc:ringBgColor="@color/white2"    tc:ringColor="@color/colorRed"    android:visibility="gone"    tc:strokeWidth="10dip" />4.主布局调用
//进度条CompletedView mTasksView;private int mTotalProgress = 0;private int mCurrentProgress = 100;mTasksView = (CompletedView) findViewById(R.id.tasks_view);
new Thread(new ProgressRunable()).start();

class ProgressRunable implements Runnable {    @Override    public void run() {        while (mCurrentProgress > mTotalProgress) {            mCurrentProgress -= 1;            mTasksView.setProgress(mCurrentProgress);            try {                Thread.sleep(50);            } catch (Exception e) {                e.printStackTrace();            }        }    }}