Hey there! Let's walk through how to handle your widget form submission and render your plugin's first view properly in WordPress—this is a common workflow, so I'll break it down step by step with actionable code snippets.

First, make sure your widget's form points to the page where your first view will live. We'll use a GET request so the selected dropdown value is passed in the URL (easy to retrieve later).

Here's how your widget class might look:

class Your_Guide_Widget extends WP_Widget {
    public function __construct() {
        parent::__construct(
            'your_guide_widget',
            'Guide Selector Widget',
            array('description' => 'Pick an option to see your guide link')
        );
    }

    // Frontend widget display
    public function widget($args, $instance) {
        echo $args['before_widget'];
        echo $args['before_title'] . 'Choose Your Guide' . $args['after_title'];
        
        // Render the form
        $target_page = get_page_by_path('your-first-view-slug'); // Replace with your page's slug
        if ($target_page) {
            $form_action = esc_url(get_permalink($target_page->ID));
            echo '<form method="GET" action="' . $form_action . '">';
            echo '<select name="guide_option" required>';
            echo '<option value="">Select an option...</option>';
            echo '<option value="beginner">Beginner Guide</option>';
            echo '<option value="advanced">Advanced Guide</option>';
            echo '</select>';
            echo '<input type="submit" value="View Guide" class="button button-small">';
            echo '</form>';
        }
        
        echo $args['after_widget'];
    }

    // Admin widget setup (optional, adjust if you need configurable options)
    public function form($instance) {
        // Leave empty or add admin settings if needed
    }
}

// Register the widget
function register_your_guide_widget() {
    register_widget('Your_Guide_Widget');
}
add_action('widgets_init', 'register_your_guide_widget');

Next, we'll build the first view using a shortcode (easy to add to any WordPress page). This shortcode will grab the submitted dropdown value, generate the appropriate guide link, and render the view content.

function your_plugin_first_view_shortcode($atts) {
    // Sanitize the submitted value to avoid security risks
    $selected_option = isset($_GET['guide_option']) ? sanitize_text_field($_GET['guide_option']) : '';
    
    // Generate the guide link based on the selected option
    $guide_link = '';
    if ($selected_option) {
        // Replace with your actual guide URLs or logic
        switch ($selected_option) {
            case 'beginner':
                $guide_url = '#beginner-guide-section'; // Or a full URL like home_url('/guides/beginner/')
                $guide_text = 'Start the Beginner Guide';
                break;
            case 'advanced':
                $guide_url = '#advanced-guide-section';
                $guide_text = 'Access Advanced Resources';
                break;
            default:
                $guide_url = '#default-guide';
                $guide_text = 'View General Guide';
        }
        $guide_link = '<a href="' . esc_url($guide_url) . '" class="plugin-guide-link button">'. esc_html($guide_text) .'</a>';
    }

    // Output the view content (use ob_start() to capture HTML)
    ob_start();
    ?>
    <div class="plugin-first-view">
        <h2>Welcome to Your Guide Hub</h2>
        <?php if ($guide_link) : ?>
            <p>Based on your selection, here's your personalized guide:</p>
            <div class="guide-link-container">
                <?php echo $guide_link; ?>
            </div>
        <?php else : ?>
            <p>Please use the widget on the side to select a guide option first.</p>
        <?php endif; ?>
    </div>
    <?php
    return ob_get_clean();
}
add_shortcode('plugin_first_view', 'your_plugin_first_view_shortcode');

1. Create a new page in WordPress (Pages → Add New)
2. Give it a slug that matches your-first-view-slug (from Step 1)
3. Paste the shortcode [plugin_first_view] into the page content and publish it

• Always sanitize user input: We used sanitize_text_field() for the dropdown value to prevent XSS attacks.
• Escape output: esc_url() and esc_html() ensure URLs and text are safe to render.
• If you prefer POST requests instead of GET, use WordPress's admin-post.php endpoint to handle submission, then redirect to the first view page with the value stored in a transient or session.

If you want the first view to live at a custom URL like yoursite.com/guide-view/ instead of a regular page, add these rewrite rules:

function your_plugin_add_rewrite_rules() {
    add_rewrite_rule(
        '^guide-view/?$',
        'index.php?plugin_guide_view=1',
        'top'
    );
}
add_action('init', 'your_plugin_add_rewrite_rules');

// Add custom query variable
function your_plugin_add_query_vars($vars) {
    $vars[] = 'plugin_guide_view';
    return $vars;
}
add_filter('query_vars', 'your_plugin_add_query_vars');

// Render the view when the custom URL is accessed
function your_plugin_render_guide_view() {
    if (get_query_var('plugin_guide_view')) {
        echo do_shortcode('[plugin_first_view]');
        exit; // Stop loading the default theme template
    }
}
add_action('template_redirect', 'your_plugin_render_guide_view');

Don't forget to go to Settings → Permalinks and click "Save Changes" to refresh WordPress's rewrite rules after adding this code.

内容的提问来源于stack exchange，提问作者Alessio Firenze