Interface DynamicBottomBarItem

Initial badge text drawn over the tab's icon. Omit for no badge.

Colors come from the bar-wide badgeBackground / badgeTextColor. To set, change or clear a badge on the running bar, use BottomBar.updateTabBadge — updateStyle only restyles badges, it never changes their content.

URL of the tab's icon. The app downloads it when the bar is rendered and keeps it cached afterwards.

The URL must be https — an http URL is refused, and the tab is left without an icon.

What the image must be

The bar repaints the icon in the tab's color: only the image's transparent and non-transparent areas matter — the shape they draw is what you see, filled with selectedColor or unselectedColor. The icon's own colors are discarded, so a full-color image comes out as a flat colored blob.

• Format: PNG with a transparent background (a real alpha channel). A white or otherwise opaque background is itself painted over, so the tab renders as a solid square of the tab color.
• Draw the glyph in a single flat color (black is the usual choice) and let the bar tint it. Do not bake in the brand color or the selected/unselected states — the bar applies both.
• Square image (1:1). The image is resized to iconSize (default 24) without being stretched, so a non-square image ends up with empty space around it and looks smaller than its neighbors.
• Around 96x96 px is the reference size — large enough to stay sharp on high-density screens without wasting bytes. Using it across a brand's icons keeps them consistent.
• Keep the padding uniform across a brand's set: the glyph should occupy the same fraction of the canvas in every icon, otherwise some tabs look bigger than others even though the boxes are identical.

An icon is re-downloaded only when its URL differs from the one currently displayed, so reusing the same URL avoids flicker.

Parameters handed to the Eitri-App when the tab opens — the way repeated slug values are disambiguated (e.g. { "route": "Categories", "tabIndex": 1 }).

Slug of the Eitri-App this tab opens. Several tabs may repeat the same slug and tell themselves apart through initParams.

The tab's label. An empty title makes the tab label-less (icon only) regardless of the theme's labels setting.