Android Spans

Kotlin and Java wrappers around SpannableStringBuilder.
Inspired by JakeWharton's Truss and Kotlin's kotlinx.html

Supported Spans:

AbsoluteSizeSpan AlignmentSpan BackgroundColorSpan BulletSpan ClickableSpan DrawableMarginSpan ForegroundColorSpan IconMarginSpan ImageSpan LeadingMarginSpan MaskFilterSpan QuoteSpan RelativeSizeSpan ScaleXSpan StrikethroughSpan StyleSpan SubscriptSpan SuperscriptSpan TextAppearanceSpan TypefaceSpan URLSpan UnderlineSpan

Usage

Kotlin

• Simple example: Spans are hard?

   val span = span {
       +"Spans "
       bold {
           +"are "
           strikethrough { +"hard?" }
       }
   }
   textView.text = span.build()

• Advanced example

   val span = span {
       text("Regular text\n")
       +"Or with the 'plus operator'\n"
  
       /*Nested spans*/
       bold {
           backgroundColor(Color.BLACK) {
               foregroundColor(Color.BLUE) {
                   +"Nested spans"
               }
           }
           +" works too!\n"
       }
  
       /*Click callback*/
       quote(Color.RED) {
           url("https://google.com", { println(it.url); /*redirect?*/ true }) {
               monospace {
                   +"Google"
               }
           }
       }
  
       /*Anonymous Span classes*/
       strikethrough(object : StrikethroughSpan() {
           override fun updateDrawState(ds: TextPaint?) {
               super.updateDrawState(ds)
               ds?.alpha = 50
           }
       }) {
           +"\nstrikethrough with alpha"
       }
   }
   textView.text = span.build()

Java

• Simple example: Spans are hard!

   Span span = Span.create(
       "Spans ",
       bold(
           "are ",
           strikethrough("hard?")
       )
   );
   textView.setText(span.build());

• Advanced example

   Span span = Span.create(
       text("Regular text\n"),
       "Or with the String\n",
  
       /*Nested spans*/
       bold(
           backgroundColor(Color.BLACK,
               foregroundColor(Color.BLUE,
                   text("Nested spans")
               )),
           text(" works too!\n")
       ),
  
       /*Click callback*/
       quote(
           Color.RED,
           url(
               "https://google.com",
               monospace(
                   text("Google")
               )
           ).onClick(new Span.Node.UrlSpanNode.OnClickCallback() {
               @Override
               public boolean onClick(URLSpan span) {
                   System.out.println(span.getURL());
                   return true;
               }
           })
       ),
  
       /*Anonymous Span classes*/
       span(new StrikethroughSpan() {
                @Override
                public void updateDrawState(TextPaint ds) {
                 super.updateDrawState(ds);
                   ds.setAlpha(50);
               }
           },
           text("\nstrikethrough with alpha")
       )
   );
   textView.setText(span.build());

License

Copyright 2017 Simon Marquis

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.