自定义属性，使用步骤

 <declare-styleable name="FillInInfoView">
        <attr name="pic" format="reference"/>
        <attr name="etHint" format="string"/>
    </declare-styleable>

   TypedArray ta = getContext().obtainStyledAttributes(attrs, R.styleable.FillInInfoView);
        Drawable drawable = ta.getDrawable(R.styleable.FillInInfoView_pic);
        String string = ta.getString(R.styleable.FillInInfoView_etHint);
        ta.recycle();

TypedArray a = context.getTheme().obtainStyledAttributes(attrs, R.styleable.CircleView, defStyleAttr, 0);
        int n = a.getIndexCount();
        for (int i = 0; i < n; i++) {
            int arr = a.getIndex(i);
            switch (arr) {
                case R.styleable.CircleView_innerCircleColor:
                    innerColor = a.getColor(arr, Color.BLUE);
                    break;
                case R.styleable.CircleView_innerCircleSize:
                    innerCircleSize = a.getDimensionPixelSize(arr, (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, 20, getResources().getDisplayMetrics()));
                    break;
                case R.styleable.CircleView_outCircleSize:
                    outCircleSize = a.getDimensionPixelSize(arr, (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, 20, getResources().getDisplayMetrics()));
                    break;
                case R.styleable.CircleView_smallCircleSize:
                    outSmallCircleSize = a.getDimensionPixelSize(arr, (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, 20, getResources().getDisplayMetrics()));
                    break;
                case R.styleable.CircleView_smallCircleRadiousSize:
                    outSmallCircleRadiousSize = a.getDimensionPixelSize(arr, (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, 20, getResources().getDisplayMetrics()));
                    break;
            }
        }
        a.recycle();