Instance Method インスタンスメソッド

background(_:in:fillStyle:)

Sets the view’s background to a shape filled with a style.

Declaration 宣言 

func background<S, T>(_ style: S, in shape: T, fillStyle: FillStyle = FillStyle()) -> some View where S : ShapeStyle, T : Shape

Return Value 戻り値

A view with the specified shape drawn behind it.

Parameters パラメータ

style

A ShapeStyle that SwiftUI uses to the fill the shape that you specify.

shape

An instance of a type that conforms to Shape that SwiftUI draws behind the view.

fillStyle

The FillStyle to use when drawing the shape. The default style uses the nonzero winding number rule and antialiasing.

Discussion 議論

Use this modifier to layer a type that conforms to the Shape protocol behind a view. Specify the ShapeStyle that’s used to fill the shape. For example, you can create a Path that outlines a trapezoid:


let trapezoid = Path { path in
    path.move(to: .zero)
    path.addLine(to: CGPoint(x: 90, y: 0))
    path.addLine(to: CGPoint(x: 80, y: 50))
    path.addLine(to: CGPoint(x: 10, y: 50))
}

Then you can use that shape as a background for a Label:


Label("Flag", systemImage: "flag.fill")
    .padding()
    .background(.teal, in: trapezoid)

The teal color fills the shape:

A screenshot of the flag icon and the word flag inside a trapezoid;

This modifier and background(_:in:fillStyle:) are convenience methods for placing a single shape behind a view. To create a background with other View types — or with a stack of views — use background(alignment:content:) instead. To add a ShapeStyle as a background, use background(_:ignoresSafeAreaEdges:).