Unfortunately, the code doesn’t work in Cocos Creator 3.6.1, so right here is the up to date code:

makeResponsive() {
    let deviceResolution = view.getViewportRect();
    let deviceRatio = deviceResolution.width / deviceResolution.top;

    let canvasResolution = view.getDesignResolutionSize();
    let canvasRatio = canvasResolution.width / canvasResolution.top;

    if (deviceRatio > canvasRatio) {
        view.setResolutionPolicy(ResolutionPolicy.FIXED_HEIGHT);
    } else {
        view.setResolutionPolicy(ResolutionPolicy.FIXED_WIDTH);
    }
}

*You must learn the unique tutorial (linked above) if you happen to don’t perceive the aim of this code snippet.