Check out example codes for "ion button outline". It will help you in understanding the concepts better.

Code Example 1

<ion-button color="primary">Primary</ion-button>

Code Example 2

<ion-button color="primary" fill="outline">Primary</ion-button>

Code Example 3

<!-- Default -->
<ion-button>Default</ion-button>

<!-- Anchor -->
<ion-button href="#">Anchor</ion-button>

<!-- Colors -->
<ion-button color="primary">Primary</ion-button>
<ion-button color="secondary">Secondary</ion-button>
<ion-button color="tertiary">Tertiary</ion-button>
<ion-button color="success">Success</ion-button>
<ion-button color="warning">Warning</ion-button>
<ion-button color="danger">Danger</ion-button>
<ion-button color="light">Light</ion-button>
<ion-button color="medium">Medium</ion-button>
<ion-button color="dark">Dark</ion-button>

<!-- Expand -->
<ion-button expand="full">Full Button</ion-button>
<ion-button expand="block">Block Button</ion-button>

<!-- Round -->
<ion-button shape="round">Round Button</ion-button>

<!-- Fill -->
<ion-button expand="full" fill="outline">Outline + Full</ion-button>
<ion-button expand="block" fill="outline">Outline + Block</ion-button>
<ion-button shape="round" fill="outline">Outline + Round</ion-button>

<!-- Icons -->
<ion-button>
  <ion-icon slot="start" name="star"></ion-icon>
  Left Icon
</ion-button>

<ion-button>
  Right Icon
  <ion-icon slot="end" name="star"></ion-icon>
</ion-button>

<ion-button>
  <ion-icon slot="icon-only" name="star"></ion-icon>
</ion-button>

<!-- Sizes -->
<ion-button size="large">Large</ion-button>
<ion-button>Default</ion-button>
<ion-button size="small">Small</ion-button>

Code Example 4

<ion-button (click)="onClick()" fill="clear">
      <ion-icon slot="icon-only" name="home"></ion-icon>
</ion-button>

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