Image

    Image is used to render images. Images may either be downloaded from the web, or imported as files, which are then bundled with the app.

    To bundle an image in the app, import the image file by its path, including the file extension. When loading bundled images, the same images are used to render on both iOS and Android. Writing import './test.png' will choose the most appropriate image for the device size: test.png, test@2x.png, or test@3x.png.

    Layout works differently for images downloaded from the web and those imported as files.

    • Imported images: the image file is scanned at build-time, and the image's dimensions are included as metadata in the app bundle. The dimensions of an Image component are then set to image's dimensions by default.
    • Images from the web: the dimensions of the image aren't known at build-time, so the width and height of the Image are set to 0 by default. In order for the image to show up on the screen, we need to either set the width and height or a flex value in the style of the Image. If the dimensions are known ahead-of-time, then they may be passed in the source prop along with the uri.

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