Failed to add color to the cube

[freedomspiritJohn]

I used a line segment to spell a cube, but when I wanted to fill him in the color, there was an abnormality. How should I solve it?

[freedomspiritJohn]

i resloved my problem with xml

<shape name="stencilName" h="100" w="100" aspect="variable" strokewidth="inherit">
  <background>
    <path>
      <move x="0" y="100"/>
      <line x="0" y="70"/>
      <line x="30" y="70"/>
      <line x="30" y="100"/>
      
      
      <close/>
      <move x="0" y="70"/>
      <line x="14" y="55"/>
      <line x="44" y="55"/>
      <line x="44" y="85.8"/>
      <line x="30" y="100"/>
      
      <move x="14" y="55"/>
      <line x="28" y="41"/>
      <line x="58" y="41"/>
      <line x="58" y="71"/>
      <line x="44" y="85.8"/>

      <move x="28" y="41"/>
      <line x="42" y="27"/>
      <line x="72" y="27"/>
      <line x="72" y="57"/>
      <line x="58" y="71"/>

      <move x="30" y="70"/>
      <line x="44" y="55"/>
      <line x="58" y="41"/>
      <line x="72" y="27"/>
    </path>
  </background>
  <foreground>
    <fillstroke/>
    <path>
      
    </path>
    <stroke/>
  </foreground>
</shape>