Bootstrap 3 vs Bootstrap 4

Support for Bootstrap 3 was added in AppStudio 6. Since then, Bootstrap 4 has been released.

There are many changes in Bootstrap 4: more than we could build a migration for in AppStudio 7. We ended up making Bootstrap 4 a separate framework. We will continue to support Bootstrap 3 for existing projects, but recommend using Bootstrap 4 for new projects.

We were able to make most of the changes in our code, so the controls work pretty much the same way. The code emitted by AppStudio is quite different.

Since Bootstrap 3 and Bootstrap 4 share many internal variable names, controls from the two frameworks cannot be included in the same project.

Here's are a couple of detailed summaries of the changes from Bootstrap 3 to Bootstrap 4:

• https://getbootstrap.com/docs/4.2/migration/
• https://www.quackit.com/bootstrap/bootstrap_4/differences_between_bootstrap_3_and_bootstrap_4.cfm

Summary of notable changes

All controls

• The default font size has been increased from 14px to 16px.

Button:

• Extra small size is gone.
• No more 'default' appearance.
• Secondary, light and dark added to appearances.
• New outline property makes outline only Buttons.
• New iconTitle displays text while hovering above.

Card

• New control for displaying formatted information.

Fliptoggle

• replaced by Switch

Icons

• Based on Open Iconic.
• Names of some icons have changed.
• Rotation no longer built in.
• Much smaller! 372k went down to 24k.

Label

• Replaced by Badges and Alerts.
• We left a simple Label control in BS4.

Media:

• imageHorizontal and imageAlignment properties dropped.

Modal:

• Footer text is always aligned right
• long text scrolls automatically
• Children are in footer.
• vertical position can be selected.

Navs

• New control.

Pageheader

• Dropped

Panel:

• Dropped

Tabs

• Dropped - replaced by Navs.

Thumbnail

• Dropped

Themes

• Dropped: readable and paper
• Added: lux, materia, minty, pulse and solar