I have implemented a dropdown menu as a navigation tool. My goal is to navigate to a selected page when an item is chosen. Here’s what I have so far:
= dropdown (@group, “menus”, @group.menus.map { |m| m.name }, { :onchange => “send_to_ruby(#{ render edit_group_menu_path(@group, this.value)})” } )To achieve the transfer of a JavaScript variable to Ruby using a dropdown navigation, you can leverage JavaScript (or jQuery) to handle the onchange event and then perform a navigation or make an AJAX request to send the variable to the server. Here’s how you can do it with JavaScript alone, using the dropdown’s onchange event to dynamically navigate to the selected page. Note that this.value within JavaScript should be used to get the selected value from the dropdown, and you can’t directly use it within the Ruby code like that. Instead, you’ll need to construct the URL dynamically in JavaScript. Here’s an example solution:
<script>
function send_to_ruby(selectedValue) {
// Assuming the URL structure is something like /groups/:group_id/menus/:menu_id/edit
var group_id = <%= @group.id %>;
var url = `/groups/${group_id}/menus/${selectedValue}/edit`;
window.location.href = url;
}
</script>
<%= dropdown(@group, 'menus', @group.menus.map { |m| [m.name, m.id] }, { onchange: 'send_to_ruby(this.value)' }) %>
In this example:
send_to_ruby JavaScript function constructs the URL dynamically using the group_id and the selected menu_id (passed as selectedValue).window.location.href property is used to navigate to the constructed URL.dropdown helper generates the dropdown menu and attaches the onchange event, passing the selected menu ID to the send_to_ruby function when the selection changes.By using this approach, you dynamically generate the URL in JavaScript and navigate to the desired page when an item from the dropdown is selected. This way, you don’t need to mix JavaScript code directly into Ruby and can still achieve the functionality you want.
To send a JavaScript variable to a Ruby backend using a dropdown navigation, you can use JavaScript to handle the onchange event of the dropdown. Here is a more detailed approach leveraging JavaScript to dynamically navigate the user to a new page based on their selection in the dropdown without directly mixing JavaScript code within the Ruby code. This approach ensures better separation of concerns and cleaner code structure. Here’s how you can achieve this solution: First, let’s assume you have a dropdown helper method. You will need to modify it to pass both the names and IDs of your menus. Then, you can handle the onchange event to construct and navigate to the URL. For clarity, the process can be broken down into the following steps: 1. Create the dropdown menu and handle the onchange event to call a JavaScript function. 2. Implement the JavaScript function to build the URL using the selected menu ID and navigate to that URL. Here’s an example: html <!-- JavaScript to handle dropdown change --> <script> function sendToRuby(selectedValue) { // Assuming the URL structure is something like /groups/:group_id/menus/:menu_id/edit var groupId = <%= @group.id %>; var url = `/groups/${groupId}/menus/${selectedValue}/edit`; // Navigate to the constructed URL window.location.href = url; } </script> <!-- Dropdown menu with onchange event --> <%= select_tag 'menus', options_for_select(@group.menus.map { |m| [m.name, m.id] }), { onchange: 'sendToRuby(this.value)' } %> In the example above: 1. The sendToRuby JavaScript function accepts the selected menu ID as an argument, constructs the URL using the group ID and selected menu ID, and then navigates to that URL. 2. The select_tag helper generates the dropdown menu with an onchange event that calls the sendToRuby function, passing the selected menu ID (this.value) as an argument. By using this approach, you dynamically generate the URL in JavaScript and navigate to the desired page when an item from the dropdown is selected. This method ensures you keep your JavaScript and Ruby code separated, leading to a more maintainable and readable codebase.