Using Font Awesome 5 SVGs as JavaFX Button shapes

Question

I'm currently developing undecorated JavaFX application and trying to add close, maximize and minimize buttons and setting their shape to a Font Awesome 5 SVG.

But some SVGs don't seem to appear correctly, for example "window-minimize" apears as just a block. (See image)

FXML For the buttons

<Button fx:id="min" mnemonicParsing="false">
 <HBox.margin>
  <Insets right="2.5" />
 </HBox.margin>
</Button>
<Button fx:id="max" mnemonicParsing="false">
 <HBox.margin>
  <Insets left="2.5" right="2.5" />
 </HBox.margin></Button>
<Button fx:id="exit" mnemonicParsing="false">
 <HBox.margin>
  <Insets left="2.5" />
 </HBox.margin>
</Button>

CSS Applied

#toolbar .button {
    -fx-background-color: #ecf0f1;

    -size: 16px;

    -fx-min-width: -size;
    -fx-min-height: -size;
    -fx-pref-width: -size;
    -fx-pref-height: -size;
}

#exit {
    -fx-shape: "M193.94 256L296.5 153.44l21.15-21.15c3.12-3.12 3.12-8.19 0-11.31l-22.63-22.63c-3.12-3.12-8.19-3.12-11.31 0L160 222.06 36.29 98.34c-3.12-3.12-8.19-3.12-11.31 0L2.34 120.97c-3.12 3.12-3.12 8.19 0 11.31L126.06 256 2.34 379.71c-3.12 3.12-3.12 8.19 0 11.31l22.63 22.63c3.12 3.12 8.19 3.12 11.31 0L160 289.94 262.56 392.5l21.15 21.15c3.12 3.12 8.19 3.12 11.31 0l22.63-22.63c3.12-3.12 3.12-8.19 0-11.31L193.94 256z";
}

#max {
    -fx-shape: "M464 32H48C21.5 32 0 53.5 0 80v352c0 26.5 21.5 48 48 48h416c26.5 0 48-21.5 48-48V80c0-26.5-21.5-48-48-48zm0 394c0 3.3-2.7 6-6 6H54c-3.3 0-6-2.7-6-6V192h416v234z";
}

#min {
    -fx-shape: "M480 480H32c-17.7 0-32-14.3-32-32s14.3-32 32-32h448c17.7 0 32 14.3 32 32s-14.3 32-32 32z";
}

Answer 1

By default the shape is scaled to fit the area of the Region it's applied to. This scaling results in a a almost quadratic look of the shape for the minimize button. Using the unscaled shape is not an option either, since the shapes are much too large for this.

Use -fx-background-insets to create the correct ratio. Furthermore I recommend putting a Region inside the Button as graphic and applying the shape to this node. This allows you to add a background to the button or increase the hitbox:

<Button fx:id="min" mnemonicParsing="false" pickOnBounds="true">
 <HBox.margin>
  <Insets right="2.5" />
 </HBox.margin>
 <graphic>
   <Region styleClass="shape"/>
 </graphic>
</Button>
<Button fx:id="max" mnemonicParsing="false" pickOnBounds="true">
 <HBox.margin>
  <Insets left="2.5" right="2.5" />
 </HBox.margin>
 <graphic>
   <Region styleClass="shape"/>
 </graphic>
</Button>
<Button fx:id="exit" mnemonicParsing="false" pickOnBounds="true">
 <HBox.margin>
  <Insets left="2.5" />
 </HBox.margin>
 <graphic>
   <Region styleClass="shape"/>
 </graphic>
</Button>

#toolbar .button {
    -size: 20px;
    -fx-padding: 2px;
    -fx-background-color: null;

    -fx-min-width: -size;
    -fx-min-height: -size;
    -fx-pref-width: -size;
    -fx-pref-height: -size;
}

#toolbar .button .shape {
    -fx-background-color: #ecf0f1;
}

#toolbar .button:pressed .shape {
    /* different background for pressed button */
    -fx-background-color: lightgreen;
}

#exit .shape {
    -fx-shape: "M193.94 256L296.5 153.44l21.15-21.15c3.12-3.12 3.12-8.19 0-11.31l-22.63-22.63c-3.12-3.12-8.19-3.12-11.31 0L160 222.06 36.29 98.34c-3.12-3.12-8.19-3.12-11.31 0L2.34 120.97c-3.12 3.12-3.12 8.19 0 11.31L126.06 256 2.34 379.71c-3.12 3.12-3.12 8.19 0 11.31l22.63 22.63c3.12 3.12 8.19 3.12 11.31 0L160 289.94 262.56 392.5l21.15 21.15c3.12 3.12 8.19 3.12 11.31 0l22.63-22.63c3.12-3.12 3.12-8.19 0-11.31L193.94 256z";
}

#max .shape {
    -fx-shape: "M464 32H48C21.5 32 0 53.5 0 80v352c0 26.5 21.5 48 48 48h416c26.5 0 48-21.5 48-48V80c0-26.5-21.5-48-48-48zm0 394c0 3.3-2.7 6-6 6H54c-3.3 0-6-2.7-6-6V192h416v234z";
}

#min .shape {
    -fx-background-insets: 6px 0 6px 0; /* use proper area for shape */
    -fx-shape: "M480 480H32c-17.7 0-32-14.3-32-32s14.3-32 32-32h448c17.7 0 32 14.3 32 32s-14.3 32-32 32z";
}