<?php
add_action('admin_menu', 'dynimg_add_admin_menu');
add_action('admin_init', 'dynimg_settings_init');

function dynimg_add_admin_menu(){
    add_menu_page('DynImg', 'DynImg', 'manage_options', 'dynimg', 'dynimg_options_page');
}

function dynimg_settings_init(){
    register_setting('dynImg', 'dynimg_settings');

    add_settings_section(
        'dynimg_pluginPage_section',
        __('Your section description', 'dynimg'),
        'dynimg_settings_section_callback',
        'pluginPage'
    );

    add_settings_field(
        'dynimg_text_field_0',
        __('Settings field description', 'dynimg'),
        'dynimg_text_field_0_render',
        'pluginPage',
        'dynimg_pluginPage_section'
    );

    add_settings_field(
        'dynimg_text_field_1',
        __('Settings field description', 'dynimg'),
        'dynimg_text_field_1_render',
        'pluginPage',
        'dynimg_pluginPage_section'
    );
}

function dynimg_text_field_0_render(){
    $options = get_option('dynimg_settings');
    ?>
    <input type='text' name='dynimg_settings[dynimg_text_field_0]' value='<?php echo $options['dynimg_text_field_0']; ?>'>
    <?php
}

function dynimg_text_field_1_render(){

    $options = get_option('dynimg_settings');
    ?>
    <input type='text' name='dynimg_settings[dynimg_text_field_1]' value='<?php echo $options['dynimg_text_field_1']; ?>'>
    <?php
}

function dynimg_settings_section_callback(){

    echo __('This section description', 'dynimg');
}

function dynimg_options_page() {
    ?>
    <form action='options.php' method='post'>
        <h2>DynImg</h2>
        <?php
        settings_fields('pluginPage');
        do_settings_sections('pluginPage');
        submit_button();
        ?>
    </form>
    <?php
}