Fillable Fly-Through


Build the form described in this fly-through and you’ll understand the basics. The rest of this User’s Guide will fill in the details of Fillable's operation, introducing additional functions and showing you alternative ways of doing some of the things covered in the fly-through.

Constructing a fillable form with Fillable is easy. You start with a  “flat” PDF image of your form; it looks like a form but can’t be filled in. Using Fillable, you lay out fields over the PDF image. When you save it, the fields are “baked into” the PDF and it becomes fillable. Then any user can open it in Preview, fill it in, and save it.

You love chinchillas so much that you’ve decided to start “Chinchillas-R-Us,” a business boarding them. One thing you’ll need will be a registration form to check in new clients.

Legibility is important, so paper forms are out. You also want to make it easy for clients to download, complete, and print the form at home if they wish. That makes it easier on everyone because it lets you focus on the pet rather than the paperwork. You decide that a PDF fill-in form will fit your needs perfectly.

NOTE: In several places in this fly-through you’ll see a “PRO-TIP” heading indicating material that doesn’t strictly belong in the fly-through. It’s included because the context is perfect for introducing the additional useful information. You don’t have to be a pro to benefit from these tips, but they will make you feel like one. :-)d.


You use your favorite word processing or graphics app — such as Pages – to create the form. Then you save it as a PDF file. This gives you a “flat” form that could be printed out and filled in by hand. But it’s also the first step toward making the fill-in form you need.

Taking a peek ahead, this is what your completed form will look like when it’s filled in:


Launch Fillable. Its menu bar and tool palette will appear. Open Chinchillas-R-Us.pdf. It will be the background image over which you lay out form fields. 

It’s easier to lay out fields when the form is blown up. So you expand the page to be quite large by zooming in on the document several times using =. 

Notice that Fillable’s page resizing maintains a full page view as you zoom in.


Let’s look at the Preferences before starting to lay out the form. Choose Fillable > Preferences to open them.


Use the Image Opacity slider to dim the background image. This will decrease eyestrain while you’re sketching fields onto the form, making it easier to focus on the fields as you lay them out. The fields you sketch will not be dimmed by the slider. And it doesn’t affect the final form; the image there will not be dimmed at all.

Since your background image doesn’t contain borders for check boxes, click Field Shading for check boxes. That will provide a way for the user to know where to click when filling in the form. This won’t affect the form’s appearance during construction, but check boxes will be shaded in the output PDF.

Note that text fields don’t need shading because they’re more clearly demarcated and more easily discoverable; you can see the text pointer when you mouse over one.

You can play with the Stroke preferences as you’re laying out the form to find the settings that make it easiest for you to work with fields.

The Fonts preferences can wait for now, but you’ll need to set them before you save the final version of your form. They’ll be registered in the form and will be used by Preview when the form is filled in.


A typical drawing app, Fillable has a palette of tools. The arrow tool is used for selecting, resizing, and moving fields. The other tools correspond to the type of field that is sketched when they’re selected.



Select the text field tool on the tool palette. When you move the mouse pointer over your document window, it changes from an arrow to a plus sign (+). Sketch out a wide, thin rectangle for the “Pet's Name” field. Notice that it has selection handles that you can use to resize it, and also that an Annotations Inspector panel has appeared. That happens whenever a single field is selected. We don’t need to do anything with the inspector right now, but it will be useful later.


Before you continue sketching text fields, it’s useful to understand how positioning and resizing work.

You want to adjust the text field you just sketched to be a certain size and in a particular location.

Go back to the tool palette and select the arrow tool.

You can adjust a selected field’s position by dragging the field. You can fine-tune its position a pixel at a time using the arrow keys. 

You can resize a selected field by dragging one of its handles. Dragging the corner handles allows both horizontal and vertical resizing. Dragging the mid-line handles only allows you to resize perpendicularly to the line the handle is on.

You can fine-tune the height and width of a selected field a pixel at a time using the arrow keys. Option-Up raises it, Option-Down lowers it, Option-Left shrinks it, and Option-Right expands it.

Fiddle with the text field you just sketched to position and resize it the way you want.


There are two approaches to doing text field layout, one in which you copy and paste existing fields to create new ones. Alternatively, you could continue to sketch fields iteratively with the mouse; it’s your choice. Let’s look now at the copy and paste method.

Be sure the arrow tool is selected for this.

The recipe for building a form by copying and pasting is to iteratively copy and then paste one of the completed fields. The pasted item will appear just below the original, slightly offset to the right. Drag it to its destination and lengthen or shorten it. Repeat this, moving down the form rapidly. The fields you’ve laid out won’t be positioned perfectly, but you’ll fine-tune them in the next phase. 

Do this with the “Pet's Name” field, dragging the pasted item into the “Weight” field. Drag the middle handle on its right end and shorten it to be the width you want.

Next, copy and paste the “Weight” field, dragging it down to the “How many times a day” field and adjusting its length.

Then copy and paste the “Pet's Name” field again, this time dragging the pasted item down to the “Own supply” field. Make it wider by dragging to the right.


Continue with this until you’ve laid out all the text fields.


If you accidentally resize a field’s height when you’re stretching or shrinking it, you can deal with that by selecting it and another field – one with the correct height – using an area selector like the one the Finder uses. Then Option-click on the good field to specify it as the anchor (it turns green) and choose the Align & Size > Make Same Height command. 

The anchor is the reference item. The command will make the other items in the selection conform to its attributes.

Note that the Align & Size commands are not enabled unless there’s a compound selection with a designated (green) anchor. 


The exception to this is Make Square, which needs no anchor and is enabled for any selection with a non-square item. We’ll use Make Square when laying out check boxes.


Now we want to add in the check boxes. We’ll use the same Copy and Paste recipe for this as we did with text fields.

Sketch the first one, adjust its size, and make it square with Align & Size > Make Square. Our check boxes all come in pairs, so copy and paste the check box. Move it into a position complementing the first one and align their bottom edges.

Then copy and paste these check boxes and move the new pair into place – adjusting their horizontal spread as needed – repeating until they’re all done. Then save the document again.


Make sure you’ve finished all of the initial layout — including fields that aren’t demarcated in the background by lines or boxes — copying and pasting fields and moving them to their needed positions.

Once all the fields are in place, you’ll want to fine-tune their positions and sizes using the arrow keys and the Align & Size commands.

For example, it’s a good idea to have the fields float a consistent distance above their underlines, so that the form has a smooth appearance when it’s been filled in. To do this, use the arrow keys like little tugboats to nudge the fields into their moorings.

Another example of fine tuning is to align the right edges of all the fields that extend to the form’s right margin to give it a crisp look. To do this, just select them, Option-click on the reference item, and choose Align & Size > Right Edges.

Now save the work you’ve done with the File > Save command (Command-S).


When the form is being filled in, you want the user to be able to tab in a logical order from field to field. In Fillable, it’s a breeze to set the fields’ tab order. Here’s how.

Click in the form to make its window active and to clear any selection.

Next, Command-click on the fields in the order in which you want to tab through them. When you’re done, click once on the form to clear the selection. That seals the tab order.


If making a mistake while setting the tab order meant that you had to start the process all over again, it would be a tense and unpleasant task, especially for long forms. But it can be performed incrementally, if need be.

When your setting of the tab order “goes off the road,” here’s what to do: Find the last item that’s in the correct tab order, select it, and Command-click on succeeding fields in the tab order you want. When you’ve finished, click once to clear the selection, resealing the tab order. It’s that simple.


Now that you can tab between fields in the order you want, it’s time to tab through them to inspect their settings and change them if necessary.

As noted earlier, an Annotations Inspector panel appears whenever you have a single field selected. As you tab through the fields, the inspector changes to show the settings for the currently selected item. Notice that the fields already have default names; these were set as you set the tab order.

When a text field is selected, Field Name, Max Length, and Alignment settings are shown. 


When a check box is selected, Field Name and “On” Value settings are shown. “On” is the default “On” Value setting (a setting that’s only useful with radio buttons).  


If you edit a field’s settings as you tab through the form, you’ll need to return focus to the form by clicking back on the selected field in order to continue tabbing. 

PRO-TIP: When you copy and paste fields, their settings are preserved. If you want a group of items to have the same settings, be sure that the first one has those settings so that the copied ones will too.


When all the field settings are correct, make sure that the Fonts preferences are set to your liking; then save the document one last time, and you’re done. You now have the Chinchillas-R-Us form for your website.


This fly-through is dedicated to John Spragens, the late cousin of my good friend Alan Spragens, who introduced me to this genre of writing. John was a creatively gifted and generous person. I’m lucky to have known him.

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