magento1.9 Add block in checkout page

Question

Add a block below discount code form

Answer 1

You can try the steps describe below to add a block in checkout cart page

Step 1)

Edit you Magento 1 Theme file checkout.xml.

I assume your current theme is "rwd default" So you need to edit the checkout.xml file under YOUR-MAGENTO-ROOT/app/design/frontend/rwd/default/layout

Insert <block type="core/template" name="checkout.cart.donation" as="donation" template="checkout/cart/donation.phtml"/> under parent block "checkout.cart.coupon" as below

...........
...........
    <checkout_cart_index translate="label">
        <label>Shopping Cart</label>
        <remove name="right"/>
        <remove name="left"/>
        <!-- Mage_Checkout -->
        <reference name="root">
            <action method="setTemplate"><template>page/1column.phtml</template></action>
        </reference>
        <reference name="content">
            <block type="checkout/cart" name="checkout.cart">
                <action method="setCartTemplate"><value>checkout/cart.phtml</value></action>
                <action method="setEmptyTemplate"><value>checkout/cart/noItems.phtml</value></action>
                <action method="chooseTemplate"/>
                <action method="addItemRender"><type>simple</type><block>checkout/cart_item_renderer</block><template>checkout/cart/item/default.phtml</template></action>
                <action method="addItemRender"><type>grouped</type><block>checkout/cart_item_renderer_grouped</block><template>checkout/cart/item/default.phtml</template></action>
                <action method="addItemRender"><type>configurable</type><block>checkout/cart_item_renderer_configurable</block><template>checkout/cart/item/default.phtml</template></action>

                <block type="core/text_list" name="checkout.cart.empty.widget" as="checkout_cart_empty_widget" translate="label">
                    <label>Empty Shopping Cart Content Before</label>
                </block>

                <block type="core/text_list" name="checkout.cart.top_methods" as="top_methods" translate="label">
                    <label>Payment Methods Before Checkout Button</label>
                    <block type="checkout/onepage_link" name="checkout.cart.methods.onepage.top" template="checkout/onepage/link.phtml" after="-" />
                </block>                

                <block type="page/html_wrapper" name="checkout.cart.form.before" as="form_before" translate="label">
                    <label>Shopping Cart Items Before</label>
                </block>

                <block type="core/text_list" name="checkout.cart.methods" as="methods" translate="label">
                    <label>Payment Methods After Checkout Button</label>
                    <block type="checkout/onepage_link" name="checkout.cart.methods.onepage.bottom" template="checkout/onepage/link.phtml"/>
                    <block type="checkout/multishipping_link" name="checkout.cart.methods.multishipping" template="checkout/multishipping/link.phtml"/>
                    <remove name="checkout.cart.methods.onepage" />                   
                </block>

                <block type="checkout/cart_coupon" name="checkout.cart.coupon" as="coupon" template="checkout/cart/coupon.phtml"/>
                <block type="core/text_list" name="checkout.cart.extra" translate="label">
                    <!-- Add Custom Donation Block-->
                    <block type="core/template" name="checkout.cart.donation" as="donation" template="checkout/cart/donation.phtml"/>
                    <label>Checkout Forms Extra</label>
                </block>                        
                <block type="checkout/cart_shipping" name="checkout.cart.shipping" as="shipping" template="checkout/cart/shipping.phtml"/>
                <block type="core/text_list" name="checkout.cart.widget" as="checkout_cart_widget" translate="label">
                    <label>Shopping Cart Items After</label>
                </block>
                <block type="checkout/cart_crosssell" name="checkout.cart.crosssell" as="crosssell" template="checkout/cart/crosssell.phtml"/>

                <block type="checkout/cart_totals" name="checkout.cart.totals" as="totals" template="checkout/cart/totals.phtml"/>
            </block>
        </reference>
        <block type="core/text_list" name="additional.product.info" translate="label">
            <label>Additional Product Info</label>
        </block>
    </checkout_cart_index>

............ ............

Step 2)

Create the phtml file donation.phtml under the active theme's checkout/cart.

I assume your current theme is "rwd default" So you need to create the donation.phtml file under

YOUR-MAGENTO-ROOT/app/design/frontend/rwd/default/template/checkout/cart/

File : donation.phtml

<form id="donation-form" name="donation-form" action="#" method="post">
    <div class="donation">        
        <div class="donation-form">            
            <div class="field-wrapper">
                <input class="input-checknot" type="checkbox" id="is_donate" name="is_donate" value="" /> Donate
                <button type="button" title="<?php echo Mage::helper('core')->quoteEscape($this->__('Add Donate')) ?>" 
                 class="button  btn-donate"><span><span><?php echo Mage::helper('core')->quoteEscape($this->__('Add Donate')) ?></span></span></button>
            </div>
        </div>
    </div>
</form>
<div class="clearer">&nbsp;</div>

<style type="text/css">
#donation-form
{
    width: 100%;
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    ont-family: "Helvetica Neue", Verdana, Arial, sans-serif;
    color: #636363;
    font-size: 14px;
    line-height: 1.5;
    padding: 10px;
    background-color: #f4f4f4;
    border: 1px solid #cccccc;
}
</style>

Note: Please change the phtml file as per your needs