<itemvalue="True if this client allows other clients to introspect it."/>
<itemvalue="introspectable"/>
<itemvalue="Creates a widget that animates its position implicitly. Only two out of the three horizontal values ([left], [right], [width]), and only two out of the three vertical values ([top], [bottom], [height]), can be set. In each case, at least one of the three must be null."/>
<itemvalue="Creates a widget that animates its position implicitly. Only two out of the three horizontal values ([left], [right], [width]), and only two out of the three vertical values ([top], [bottom], [height]), can be set. In each case, at least one of the three must be null."/>
<itemvalue="A decimal-point string-representation of this number. Converts this number to a [double] before computing the string representation, as by [toDouble]. If the absolute value of `this` is greater than or equal to `10^21`, then this methods returns an exponential representation computed by `this.toStringAsExponential()`. Otherwise the result is the closest string representation with exactly [fractionDigits] digits after the decimal point. If [fractionDigits] equals 0, then the decimal point is omitted. The parameter [fractionDigits] must be an integer satisfying: `0 <= fractionDigits <= 20`."/>