Activity 1

Change the application so that clicking a book’s image will also invoke the create action.

Hint: the first parameter to link_to is placed in the generated <a> tag, and the Rails helper image_tag constructs an HTML <img> tag. Include a call to it as the first parameter to a link_to call. Be sure to include :method => :post in your html_options on your call to link_to.

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Activity 2

Add a new variable to the session to record how many times the user has accessed the index action.

Hint: The first time through, your count won’t be in the session. You can test for this with code like


if session[:counter].nil? 
    ...

If the session variable isn’t there, you’ll need to initialize it. Then you’ll be able to increment it.

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Activity 3

Pass this counter to your template, and display it at the top of the catalog page.

Hint: the pluralize helper might be useful when forming the message you display.

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Activity 4

Reset the counter to zero whenever the user adds something to the cart.

Hint: adding something to a cart doesn’t modify the Cart, instead look to add this logic to the create method of the line_items_controller.

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Activity 5

Change the template to display the counter only if it is greater than five.

Hint: While this can be done inside the template, it should be done in the controller.

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Comments

It will be more fun to put the counter message in the error display area using flash. The requirements are: if there is no error, just display the counter; but if there is an error, then display the error and the counter. When the index page is refreshed, remove the error and update the counter.

Hint: use a session variable to keep track of whether there is a redirect.

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