自定義控件_畫圓

public class MyProgressRound extends View{

    Paint paint;

    private int mProgress = 0;
    private int mCountProgress = 0;

    private float mRadiuSize = 0;
    private float mRingSize = 0;
    private float mTextSize = 0;
    private int mProgressColor = 0;


    public MyProgressRound(Context context) {
        super(context);
        init();
    }

    /**
     * 所有在xml佈局文件中 標籤裏面聲明的屬性 都可以在AttributeSet類的對象中獲取出來
     * @param context
     * @param attrs
     */
    public MyProgressRound(Context context, @Nullable AttributeSet attrs) {
        //在該構造方法中可以獲取到  所有參數
        //把參數傳出去  在onDraw方法中可以操作  onMeasure中也可以操作
        super(context, attrs);
        getCustomAttr(context, attrs);
        init();
    }

    private void getCustomAttr(Context context, AttributeSet attrs) {
        TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.MyProgressRound);
        mRadiuSize = array.getDimension(R.styleable.MyProgressRound_radiuSize, 100);
        mRingSize = array.getDimension(R.styleable.MyProgressRound_ringSize, 10);
        mTextSize = array.getDimension(R.styleable.MyProgressRound_textSize, 10);
        mProgressColor = array.getColor(R.styleable.MyProgressRound_progressColor, Color.BLACK);

    }


    public MyProgressRound(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    public void init(){
        paint = new Paint();
        paint.setAntiAlias(true);
    }

    //widthMeasureSpec／heightMeasureSpec 是一個32爲的int類型
    //01000000 00000000 00000000 00000000
    //高兩位 代表類型
    //warpcontent類型 MeasureSpec.AT_MOST
    //matchparent類型 MeasureSpec.EXACTLY 或者具體的長度 100dp 200dp
    // 其他類型
    //
    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        int widthSize = MeasureSpec.getSize(widthMeasureSpec);
        int heightMode = MeasureSpec.getMode(heightMeasureSpec);
        int heightSize = MeasureSpec.getSize(heightMeasureSpec);

        int width = 0;
        int height = 0;
        if(widthMode == MeasureSpec.AT_MOST){
            width = (int) (mRadiuSize * 2);
        }else{
            width = Math.max(widthSize, (int) (mRadiuSize * 2));
        }

        if(heightMode == MeasureSpec.AT_MOST){
            height = (int) (mRadiuSize * 2);
        }else{
            height = Math.max(heightSize, (int) (mRadiuSize * 2));
        }

        setMeasuredDimension(width, height);

//        switch (widthMode){
//            case MeasureSpec.AT_MOST:
//                //如果寬度使用的是warp_content那麼 我們需要手動設置控件的寬值， 標準是寬是半徑的2倍
//                Log.i("=============widthMode", "onMeasure: " + "AT_MOST---> warp_content");
//                //確定了寬高後，修改控件的寬高
//                setMeasuredDimension((int)(mRadiuSize * 2), (int)(mRadiuSize * 2));
//                break;
//            case MeasureSpec.EXACTLY:
//                Log.i("=============widthMode", "onMeasure: " + "Exactly---> match_parent");
//                break;
//        }
//
//        switch (heightMode){
//            case MeasureSpec.AT_MOST:
//                Log.i("=============heightMode", "onMeasure: " + "AT_MOST---> warp_content");
//                break;
//            case MeasureSpec.EXACTLY:
//                Log.i("=============heightMode", "onMeasure: " + "Exactly---> match_parent");
//                break;
//        }



    }



    @Override
    protected void onDraw(Canvas canvas) {
        //在佈局文件中設置的圓環半徑大小就可以不用寫死
        paint.setStrokeWidth(0);
        paint.setColor(Color.BLACK);
        paint.setStyle(Paint.Style.STROKE);
        canvas.drawCircle(getMeasuredWidth()/2, getMeasuredHeight()/2, mRadiuSize, paint);
        canvas.drawCircle(getMeasuredWidth()/2, getMeasuredHeight()/2, mRadiuSize - mRingSize, paint);

        paint.setTextSize(mTextSize);
        String text = mCountProgress + "%";
        float textWidth = paint.measureText(text);
        canvas.drawText(text, getMeasuredWidth()/2-textWidth/2 , getMeasuredWidth()/2 + mTextSize/2, paint);

        RectF rectF = new RectF(getMeasuredWidth()/2 - mRadiuSize + mRingSize/2,getMeasuredHeight()/2 - mRadiuSize + mRingSize/2,getMeasuredWidth()/2 + mRadiuSize - mRingSize/2,getMeasuredHeight()/2 + mRadiuSize - mRingSize/2);
        paint.setStrokeWidth(mRingSize);
        paint.setColor(mProgressColor);
        canvas.drawArc(rectF, 0, mProgress, false, paint);
    }

    public void setProgress(int progress){
        mProgress = progress;
        mCountProgress = progress * 100 / 360;
        invalidate();
    }
}

======================================================================

public class MainActivity extends AppCompatActivity {


    MyProgressRound mpr;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);




        mpr = (MyProgressRound) findViewById(R.id.mpr);


        new AsyncTask<String, Integer, String>(){


            @Override
            protected String doInBackground(String... params) {
                for (int i = 0; i <= 360; i++) {
                    SystemClock.sleep(10);
                    publishProgress(i);
                }


                return null;
            }


            //該方法的調用條件是   publishProgress
            @Override
            protected void onProgressUpdate(Integer... values) {
                mpr.setProgress(values[0]);
            }
        }.execute();


    }
}