For some Android XML attributes, you don't conclude the opening tag with a '>' until after you've inserted your formatting components. For example:
<EditText
android:id="@+id/etEmails">
</EditText>
Why is there no definition for the EditText component within the opening and closing tags? Also, I noticed that some don't even require closing tags and are just in themselves XML statements. For example:
<Button
android:text="Subtract 1"
android:id="@+id/buttSub"
/>
Why does this XML statement not require a closing statement when it practically provides the same components as the EditText field?
Is there a failsafe way of knowing which ones require opening and closing statements for proper syntax?
Is there a list/reference for which ones do and don't?
What's the difference between these different components?