自定义view里面代码生成textview，设置了setGravity，不知道为什么文字偏下了

====================关键代码================================================
textView = TextView(context)
textView.setTextColor(this.mNumColor)
textView.background = provideItemBg()
textView.setOnClickListener { }
textView.setTextSize(TypedValue.COMPLEX_UNIT_PX, this.mNumberSize.toFloat())

if (i == 10) {
    textView.tag = true
} else {
    textView.tag = false
    textView.text =i.toString()
}
textView.setGravity(Gravity.CENTER)
addView(textView)

===================完整代码=================================================
class NumKeyboardLayout(context: Context, attrs: AttributeSet?, defStyleAttr: Int) :
    ViewGroup(context, attrs, defStyleAttr) {
    companion object {
        const val DEFAULT_NUMBER_SIZE = 20
        const val DEFAULT_RADIU = 0
    }

    //大小单位px
    private var mNumberSize = 0

    //圆角单位px
    private var mRadiu = 0

    @ColorInt
    private var mNumColor: Int = -1

    @ColorInt
    private var mItemBg: Int = -1

    @ColorInt
    private var mItemPressBg: Int = -1


    constructor(context: Context, attrs: AttributeSet?) : this(context, attrs, 0)
    constructor(context: Context) : this(context, null)

    init {
        initAttrs(context, attrs)
        initSetUpItem()
    }

    private fun initSetUpItem() {
        removeAllViews()
        var textView: TextView
        for (i in 0..10) {
            textView = TextView(context)
            textView.setTextColor(this.mNumColor)
            textView.background = provideItemBg()
            textView.setOnClickListener { }
            textView.setTextSize(TypedValue.COMPLEX_UNIT_PX, this.mNumberSize.toFloat())

            if (i == 10) {
                textView.tag = true
            } else {
                textView.tag = false
                textView.text =i.toString()
            }
            textView.setGravity(Gravity.CENTER)
            addView(textView)
        }
    }

    private fun provideItemBg(): StateListDrawable {
        //背景图按下 shape
        val itemBgPressDrawable = GradientDrawable()
        itemBgPressDrawable.setColor(this.mItemPressBg)
        itemBgPressDrawable.cornerRadius = this.mRadiu.toFloat()
        //背景图正常 shape
        val itemBgNormalDrawable = GradientDrawable()
        itemBgNormalDrawable.setColor(this.mItemBg)
        itemBgNormalDrawable.cornerRadius = this.mRadiu.toFloat()
        //背景selector
        val itemBgSelector = StateListDrawable()
        itemBgSelector.addState(intArrayOf(android.R.attr.state_pressed), itemBgPressDrawable)
        itemBgSelector.addState(intArrayOf(), itemBgNormalDrawable)
        return itemBgSelector
    }

    private fun initAttrs(context: Context, attrs: AttributeSet?) {
        val attrs = context.obtainStyledAttributes(attrs, R.styleable.NumKeyboardLayout)
        this.mNumberSize = attrs.getDimensionPixelOffset(
            R.styleable.NumKeyboardLayout_nkl_numberSize,
            ConvertUtils.dp2px(DEFAULT_NUMBER_SIZE.toFloat())
        )

        LogUtils.d("mNumberSize ==>$this.mNumberSize")

        this.mNumColor = attrs.getColor(
            R.styleable.NumKeyboardLayout_nkl_numberColor,
            context.resources.getColor(R.color.white)
        )

        this.mItemBg = attrs.getColor(
            R.styleable.NumKeyboardLayout_nkl_itemBg,
            context.resources.getColor(R.color.darkGray)
        )
        this.mItemPressBg = attrs.getColor(
            R.styleable.NumKeyboardLayout_nkl_itemPressBg,
            context.resources.getColor(R.color.darkGrayDark)
        )
        this.mRadiu = attrs.getDimensionPixelOffset(
            R.styleable.NumKeyboardLayout_nkl_radiu,
            DEFAULT_RADIU
        )

        attrs.recycle()
    }

    override fun onMeasure(widthMeasureSpec: Int, heightMeasureSpec: Int) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec)
        val widthMode = MeasureSpec.getMode(widthMeasureSpec)
        val widthSize = MeasureSpec.getSize(widthMeasureSpec)
        val heightMode = MeasureSpec.getMode(heightMeasureSpec)
        val heightSize = MeasureSpec.getSize(heightMeasureSpec)

        LogUtils.d("widthSize==> $widthSize")
        LogUtils.d("heightSize==> $heightSize")

        //item宽度
        val itemWidth = widthSize / 3
        //item高度
        val itemHeight = heightSize / 4

        val normalWidthSpace = MeasureSpec.makeMeasureSpec(itemWidth, MeasureSpec.EXACTLY)
        val heightSpace = MeasureSpec.makeMeasureSpec(itemHeight, MeasureSpec.EXACTLY)
        val deleteWidthSpace = MeasureSpec.makeMeasureSpec(itemWidth * 2, MeasureSpec.EXACTLY)
        //测量孩子
        for (i in 0 until childCount) {
            val view = getChildAt(i)

            view.measure(if (view.tag == true) deleteWidthSpace else normalWidthSpace, heightSpace)
        }
        //测量自己
        setMeasuredDimension(widthMeasureSpec, heightMeasureSpec)
    }

    override fun onLayout(changed: Boolean, l: Int, t: Int, r: Int, b: Int) {
        val item = getChildAt(0)
        item.layout(0, 0, item.measuredWidth, item.measuredWidth)
    }

    override fun getResources(): Resources {
        return super.getResources()
    }


    /**
     * 设置数字大小，单位px
     * @param size Int
     */
    fun setNumberSize(size: Int) {
        this.mNumberSize = size
    }


    fun setNumColor(@ColorInt color: Int) {
        this.mNumColor = color
    }

    fun setItemBg(@ColorInt color: Int) {
        this.mItemBg = color
    }

    fun setItemPressBg(@ColorInt color: Int) {
        this.mItemPressBg = color
    }

}