| // Small function to quickly swap out themes. Gets put into the <head> tag.. |
| function set_theme_from_local_storage() { |
| // Intialize the theme to null, which means default |
| var theme = null; |
| // If the browser supports the localstorage and is not disabled then try to get the |
| // documenter theme |
| if(window.localStorage != null) { |
| // Get the user-picked theme from localStorage. May be `null`, which means the default |
| // theme. |
| theme = window.localStorage.getItem("documenter-theme"); |
| } |
| // Check if the browser supports user color preference |
| var darkPreference = false; |
| // Check if the users preference is for dark color scheme |
| if(window.matchMedia('(prefers-color-scheme: dark)').matches === true) { |
| darkPreference = true; |
| } |
| // Initialize a few variables for the loop: |
| // |
| // - active: will contain the index of the theme that should be active. Note that there |
| // is no guarantee that localStorage contains sane values. If `active` stays `null` |
| // we either could not find the theme or it is the default (primary) theme anyway. |
| // Either way, we then need to stick to the primary theme. |
| // |
| // - disabled: style sheets that should be disabled (i.e. all the theme style sheets |
| // that are not the currently active theme) |
| var active = null; var disabled = []; var darkTheme = null; |
| for (var i = 0; i < document.styleSheets.length; i++) { |
| var ss = document.styleSheets[i]; |
| // The <link> tag of each style sheet is expected to have a data-theme-name attribute |
| // which must contain the name of the theme. The names in localStorage much match this. |
| var themename = ss.ownerNode.getAttribute("data-theme-name"); |
| // attribute not set => non-theme stylesheet => ignore |
| if(themename === null) continue; |
| // To distinguish the default (primary) theme, it needs to have the data-theme-primary |
| // attribute set. |
| var isprimary = (ss.ownerNode.getAttribute("data-theme-primary") !== null); |
| // Check if the theme is primary dark theme |
| var isDarkTheme = (ss.ownerNode.getAttribute("data-theme-primary-dark") !== null); |
| // If ss is for dark theme then set the value of darkTheme to the name of the theme |
| if(isDarkTheme) darkTheme = themename; |
| // If we find a matching theme (and it's not the default), we'll set active to non-null |
| if(themename === theme) active = i; |
| // Store the style sheets of inactive themes so that we could disable them |
| if(themename !== theme) disabled.push(ss); |
| } |
| if(active !== null) { |
| // If we did find an active theme, we'll (1) add the theme--$(theme) class to <html> |
| document.getElementsByTagName('html')[0].className = "theme--" + theme; |
| // and (2) disable all the other theme stylesheets |
| disabled.forEach(function(ss){ |
| ss.disabled = true; |
| }); |
| } |
| else if(darkTheme !== null && darkPreference === true) { |
| // If we did find an active theme, we'll (1) add the theme--$(theme) class to <html> |
| document.getElementsByTagName('html')[0].className = "theme--" + darkTheme; |
| // and (2) disable all the other theme stylesheets |
| disabled.forEach(function(ss){ |
| if (ss.ownerNode.getAttribute("data-theme-name") !== darkTheme) { |
| ss.disabled = true; |
| } |
| }); |
| } |
| } |
| set_theme_from_local_storage(); |