android群英传笔记--第三章--自定义控件三简单形状View

@Override
protected void onMeasure(int widthMeasureSpec,
int heightMeasureSpec) {
mMeasureWidth = MeasureSpec.getSize(widthMeasureSpec);
mMeasureHeigth = MeasureSpec.getSize(heightMeasureSpec);
setMeasuredDimension(mMeasureWidth, mMeasureHeigth);
initView();
}

@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
// 绘制圆
canvas.drawCircle(mCircleXY, mCircleXY, mRadius, mCirclePaint);
// 绘制弧线
canvas.drawArc(mArcRectF, 270, mSweepAngle, false, mArcPaint);
// 绘制文字
canvas.drawText(mShowText, 0, mShowText.length(),
mCircleXY, mCircleXY + (mShowTextSize / 4), mTextPaint);
}

关键逻辑方法：

private void initView() {
float length = 0;
if (mMeasureHeigth >= mMeasureWidth) {
length = mMeasureWidth;
} else {
length = mMeasureHeigth;
}

mCircleXY = length / 2;
mRadius = (float) (length * 0.5 / 2);
mCirclePaint = new Paint();
mCirclePaint.setAntiAlias(true);
mCirclePaint.setColor(getResources().getColor(
android.R.color.holo_blue_bright));

mArcRectF = new RectF(
(float) (length * 0.1),
(float) (length * 0.1),
(float) (length * 0.9),
(float) (length * 0.9));
mSweepAngle = (mSweepValue / 100f) * 360f;
mArcPaint = new Paint();
mArcPaint.setAntiAlias(true);
mArcPaint.setColor(getResources().getColor(
android.R.color.darker_gray));
mArcPaint.setStrokeWidth((float) (length * 0.1));
mArcPaint.setStyle(Style.STROKE);

mShowText = setShowText();
mShowTextSize = setShowTextSize();
mTextPaint = new Paint();
mTextPaint.setTextSize(mShowTextSize);
mTextPaint.setTextAlign(Paint.Align.CENTER);
}