NativeScript/apps/ui-tests-app/css/text-transform.xml

<Page >
  <ScrollView>
    <StackLayout>
      <Button text="Change" tap="butonTap" />
      <Label id="Label1" text="text Text" style="text-transform:none" />
      
      <Label text="label label" style="text-transform:none" />
      <Label text="label label" style="text-transform:capitalize" />
      <Label text="label label" style="text-transform:uppercase" />
      <Label text="label label" style="text-transform:lowercase" />

      <TextField text="textField textField" style="text-transform:none" />
      <TextField text="textField textField" style="text-transform:capitalize" />
      <TextField text="textField textField" style="text-transform:uppercase;" />
      <TextField text="textField textField" style="text-transform:lowercase" />
      <TextField text="textField textField" style="text-transform:uppercase; text-decoration:underline;" />

      <TextView text="textView textView" style="text-transform:none" />
      <TextView text="textView textView" style="text-transform:capitalize" />
      <TextView text="textView textView" style="text-transform:uppercase" />
      <TextView text="textView textView" style="text-transform:lowercase" />
      <TextView text="textView textView" style="text-transform:uppercase; text-decoration:underline;" />

      <Button text="button Button" style="text-transform:none" />
      <Button text="button Button" style="text-transform:capitalize" />
      <Button text="button Button" style="text-transform:uppercase" />
      <Button text="button Button" style="text-transform:lowercase" />
      <Button text="button Button" style="text-transform:uppercase; text-decoration:underline;" />

      <Label style="text-transform: uppercase; text-decoration: underline line-through;">
        <Label.formattedText>
          <FormattedString>
            <FormattedString.spans>
              <Span text="text" fontAttributes="Bold" foregroundColor="#ff0000" />
              <Span text="Text" fontAttributes="Italic" foregroundColor="#00ff00" />
            </FormattedString.spans>
          </FormattedString>
        </Label.formattedText>
      </Label>

      <Button style="text-transform: uppercase; text-decoration: underline line-through;">
        <Button.formattedText>
          <FormattedString>
            <FormattedString.spans>
              <Span text="text" fontAttributes="Bold" foregroundColor="#ff0000" />
              <Span text="Text" fontAttributes="Italic" foregroundColor="#00ff00" />
            </FormattedString.spans>
          </FormattedString>
        </Button.formattedText>
      </Button>
      
    </StackLayout>
  </ScrollView>
</Page>