建议：修改QMUIResHelper实现，以解决AS预览xml布局时不生效的问题

[1993hzw]

object QMUIResHelper {
    @JvmStatic
    fun getAttrFloatValue(context: Context, attr: Int): Float {
        return getAttrFloatValue(context.theme, attr)
    }

    @JvmStatic
    fun getAttrFloatValue(theme: Resources.Theme, attr: Int): Float {
        val sAttrResArray = IntArray(1)
        sAttrResArray[0] = attr
        val a: TypedArray = theme.obtainStyledAttributes(0, sAttrResArray)
        val v = a.getFloat(0, 0f)
        a.recycle()
        return v
    }

    @JvmStatic
    fun getAttrColor(context: Context, attrRes: Int): Int {
        return getAttrColor(context.theme, attrRes)
    }

    @JvmStatic
    fun getAttrColor(theme: Resources.Theme, attr: Int): Int {
        val sAttrResArray = IntArray(1)
        sAttrResArray[0] = attr
        val a: TypedArray = theme.obtainStyledAttributes(0, sAttrResArray)
        val v = a.getColor(0, Color.BLACK)
        a.recycle()
        return v
    }

    @JvmStatic
    fun getAttrColorStateList(context: Context, attrRes: Int): ColorStateList? {
        return getAttrColorStateList(context, context.theme, attrRes)
    }

    @JvmStatic
    fun getAttrColorStateList(
            context: Context?,
            theme: Resources.Theme,
            attr: Int
    ): ColorStateList? {
        val sAttrResArray = IntArray(1)
        sAttrResArray[0] = attr
        val a: TypedArray = theme.obtainStyledAttributes(0, sAttrResArray)
        val v = a.getColorStateList(0)
        a.recycle()
        return v
    }

    @JvmStatic
    fun getAttrDrawable(context: Context, attr: Int): Drawable? {
        return getAttrDrawable(context, context.theme, attr)
    }

    @JvmStatic
    fun getAttrDrawable(context: Context, theme: Resources.Theme, attr: Int): Drawable? {
        val sAttrResArray = IntArray(1)
        sAttrResArray[0] = attr
        val a: TypedArray = theme.obtainStyledAttributes(0, sAttrResArray)
        val v = a.getDrawable(0)
        a.recycle()
        return v
    }

    @JvmStatic
    fun getAttrDrawable(context: Context, typedArray: TypedArray, index: Int): Drawable? {
        val v = typedArray.getDrawable(index)
        typedArray.recycle()
        return v
    }

    @JvmStatic
    fun getAttrDimen(context: Context, attrRes: Int): Int {
        val sAttrResArray = IntArray(1)
        sAttrResArray[0] = attrRes
        val a: TypedArray = context.theme.obtainStyledAttributes(0, sAttrResArray)
        val v = a.getDimensionPixelOffset(0, 0)
        a.recycle()
        return v
    }

    @JvmStatic
    fun getAttrString(context: Context, attrRes: Int): String? {
        val sAttrResArray = IntArray(1)
        sAttrResArray[0] = attrRes
        val a: TypedArray = context.theme.obtainStyledAttributes(0, sAttrResArray)
        val v = a.getString(0)
        a.recycle()
        return v
    }

    @JvmStatic
    fun getAttrInt(context: Context, attrRes: Int): Int {
        val sAttrResArray = IntArray(1)
        sAttrResArray[0] = attrRes
        val a: TypedArray = context.theme.obtainStyledAttributes(0, sAttrResArray)
        val v = a.getInt(0, 0)
        a.recycle()
        return v
    }

    @JvmStatic
    fun assignTextViewWithAttr(textView: TextView, attrRes: Int) {
        val a = textView.context.obtainStyledAttributes(null, R.styleable.QMUITextCommonStyleDef, attrRes, 0)
        val count = a.indexCount
        var paddingLeft = textView.paddingLeft
        var paddingRight = textView.paddingRight
        var paddingTop = textView.paddingTop
        var paddingBottom = textView.paddingBottom
        for (i in 0 until count) {
            val attr = a.getIndex(i)
            if (attr == R.styleable.QMUITextCommonStyleDef_android_gravity) {
                textView.gravity = a.getInt(attr, -1)
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_textColor) {
                textView.setTextColor(a.getColorStateList(attr))
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_textSize) {
                textView.setTextSize(TypedValue.COMPLEX_UNIT_PX, a.getDimensionPixelSize(attr, 0).toFloat())
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_paddingLeft) {
                paddingLeft = a.getDimensionPixelSize(attr, 0)
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_paddingRight) {
                paddingRight = a.getDimensionPixelSize(attr, 0)
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_paddingTop) {
                paddingTop = a.getDimensionPixelSize(attr, 0)
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_paddingBottom) {
                paddingBottom = a.getDimensionPixelSize(attr, 0)
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_singleLine) {
                textView.isSingleLine = a.getBoolean(attr, false)
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_ellipsize) {
                val ellipsize = a.getInt(attr, 3)
                when (ellipsize) {
                    1 -> textView.ellipsize = TextUtils.TruncateAt.START
                    2 -> textView.ellipsize = TextUtils.TruncateAt.MIDDLE
                    3 -> textView.ellipsize = TextUtils.TruncateAt.END
                    4 -> textView.ellipsize = TextUtils.TruncateAt.MARQUEE
                }
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_maxLines) {
                textView.maxLines = a.getInt(attr, -1)
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_background) {
                QMUIViewHelper.setBackgroundKeepingPadding(textView, a.getDrawable(attr))
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_lineSpacingExtra) {
                textView.setLineSpacing(a.getDimensionPixelSize(attr, 0).toFloat(), 1f)
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_drawablePadding) {
                textView.compoundDrawablePadding = a.getDimensionPixelSize(attr, 0)
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_textColorHint) {
                textView.setHintTextColor(a.getColor(attr, 0))
            } else if (attr == R.styleable.QMUITextCommonStyleDef_android_textStyle) {
                val styleIndex = a.getInt(attr, -1)
                textView.setTypeface(null, styleIndex)
            }
        }
        textView.setPadding(paddingLeft, paddingTop, paddingRight, paddingBottom)
        a.recycle()
    }
}

[1993hzw]

以上代码可以使主题属性在AS上预览xml布局时看到实时效果，目前表现是只有run app时才能看得到布局效果。这个解决了可以提高布局开发效率。