<maction> - MathML 编辑

The MathML <maction> element provides a possibility to bind actions to (sub-) expressions. The action itself is specified by the actiontype attribute, which accepts several values. To specify which child elements are addressed by the action, you can make use of the selection attribute.

Attributes

actiontype

The action which specifies what happens for this element. Possible values are:

• statusline: If there is a click on the expression or the reader moves the pointer over it, the message is sent to the browser's status line. The syntax is: <maction actiontype="statusline"> expression message </maction>.
• toggle: When there is a click on the subexpression, the rendering alternates the display of selected subexpressions. Therefore each click increments the selection value.
  The syntax is: <maction actiontype="toggle" selection="positive-integer" > expression1 expression2 expressionN </maction>.
• tooltip: When the pointer moves over the expression, a tooltip box with a message is displayed near the expression.
  The syntax is:<maction actiontype="tooltip"> expression message </maction>.

class, id, style

Provided for use with stylesheets.

displaystyle

A Boolean value specifying whether more vertical space is used for displayed equations or, if set to false, a more compact layout is used to display formulas. The main effect is that larger versions of operators are displayed, when displaystyle is set to true. See also largeop and movablelimits on <mo>.

href

Used to set a hyperlink to a specified URI.

mathbackground

The background color. You can use #rgb, #rrggbb and HTML color names.

mathcolor

The text color and also the fraction line color. You can use #rgb, #rrggbb and HTML color names.

selection

The child element which is addressed by the action. The default value is 1, which is the first child element.

Examples

The following example uses the "toggle" actiontype:

<math>

<maction actiontype="toggle">

  <mfrac>
    <mn>6</mn>
    <mn>8</mn>
  </mfrac>

  <mfrac>
    <mrow>
      <mn>3</mn>
      <mo>&sdot;</mo>
      <mn>2</mn>
    </mrow>
    <mrow>
      <mn>4</mn>
      <mo>&sdot;</mo>
      <mn>2</mn>
    </mrow>
  </mfrac>

  <mfrac>
    <mn>3</mn>
    <mn>4</mn>
  </mfrac>

</maction>

</math>

Specifications

Browser compatibility

BCD tables only load in the browser

Gecko-specific notes

• Prior to Gecko 9.0 (Firefox 9.0 / Thunderbird 9.0 / SeaMonkey 2.6) the non-standard restyle value on the actiontype attribute was supported. This value has been removed.
• Prior to Gecko 14.0 (Firefox 14.0 / Thunderbird 14.0 / SeaMonkey 2.11) the statusline action type was using a non-standard syntax (see below). This has been fixed to follow the MathML specification.

  <maction actiontype="statusline#(message)">
  (expression)
  </maction>
  

• With Gecko 15.0 (Firefox 15.0 / Thunderbird 15.0 / SeaMonkey 2.12) the selection attribute is only taken into account with the actiontype "toggle".
• Starting with Gecko 16.0 (Firefox 16.0 / Thunderbird 16.0 / SeaMonkey 2.13) the selection attribute is also taken into account when an unknown actiontype is specified. If an actiontype is not specified (is empty) or when the selection attribute is invalid, the markup will throw an MathML error (invalid-markup).