Signin Screen Prototype

Part 1

Complete these steps to create a 'signin' prototype:

1. "Listen" for when the user clicks the #signin button, display the #modal window
2. "Listen" for when the user clicks the #close button, display (or fade out) out the #modal window
3. "Listen" for when the user clicks the #submit button, add an .error class to both input.field elements
   • Easy: First add the .error class to each individually using getElementById() or querySelector()
   • Advanced: Once successful, try applying to both input.field using querySelectorAll() and a forEach() (or another type of traversal loop)
4. Remove the .error class from any individual <input> when the cursor gives it focus
   • Easy: First try writing one event listener/handler per input element
   • Advanced: Then do this by writing only ONE event listener/handler for all input elements and applying it using a traversal loop

Part 2

1. In index.html change the #submit element from type="button" to type="submit". When the user triggers a submit Event for the form#getstarted, prevent the form from proceeding with it's default behavior (which is redirecting away from the page)
   • Remove the click listener from the button#submit created earlier and move the logic within it to this listener
2. On submit of the form#getstarted, only add the .error class to the input.field elements that have a value of "" (blank, meaning any content within the field will prevent an error)
   • Consider what should if the user just adds spaces to the field? Compare " " == "" in your console to test; then find a function that will trim the white spaces from a String to help validate this field
3. Prototype the form validation by checking the two input.fields on submit of the form#getstarted. If both fields are "valid" (they not blank, not including "white space" characters), do the following:
   1. Remove the #modal from view
   2. Remove the button#signin from view
   3. Append textContent to the #hello heading so it reads "Welcome, [USERNAME]"
   4. Change the font-size of the #hello heading so that it's half the current size
   5. Consider the various ways we could validate both fields, including the use of a Boolean variable as a true or false status flag
4. Try improving the user experience by adding/removing the .error class from an input.field immediately after the cursor leaves one of the individual <input> (rather than waiting for a submit event to occur)
   • Consider the blur (opposite of focus) can be added individually to each input, but should be done so by writing one event listener/callback function and using a loop to apply to each of the input.field elements at the same time
5. Allow the user to click the dark translucent background of the #modal block to have it close itself (but not the the form within it)
   • Test this and see what happens when an element inside of another element (here, the form within the .modal) is clicked. Click events will "bubble" (propagate) up the DOM tree!
   • Search for a way to stop an event (clicking the <form>) from bubbling to its parent (the .modal)