chaitanya79 / compose-richtext

A collection of Compose libraries for working with rich text formatting and documents.

compose-richtext

A collection of Compose libraries for working with rich text formatting and documents. This repo is currently very experimental and really just proofs-of-concept: there are no tests, some things might be broken or very non-performant, and it's not published on Maven. Once Compose stabilizes, if it's still useful, I might eventually polish it up and actually release something.

@Composable fun App() {
  val printController = rememberPrintableController()

  Printable(printController) {
    RichText(Modifier.background(color = Color.White)) {
      Heading(0, "Title")
      Text("Summary paragraph.")

      HorizontalRule()

      BlockQuote {
        Text("A wise person once said…")
      }
    }
  }

  Button(onClick = { printController.print("README") }) {
    Text("PRINT ME")
  }
}

Table of Contents

• richtext-ui
• printing

richtext-ui

A library of composables for formatting text using higher-level concepts than are supported by compose foundation, such as "bullet lists" and "headings".

Eventually planning to add support for rendering Markdown.

Example

Open the Demo.kt file in the richtext-ui module to play with this.

RichText(modifier = Modifier.background(color = Color.White)) {
  Heading(0, "Paragraphs")
  Text("Simple paragraph.")
  Text("Paragraph with\nmultiple lines.")
  Text("Paragraph with really long line that should be getting wrapped.")

  Heading(0, "Lists")
  Heading(1, "Unordered")
  ListDemo(listType = Unordered)
  Heading(1, "Ordered")
  ListDemo(listType = Ordered)

  Heading(0, "Horizontal Line")
  Text("Above line")
  HorizontalRule()
  Text("Below line")

  Heading(0, "Code Block")
  CodeBlock(
    """
      {
        "Hello": "world!"
      }
    """.trimIndent()
  )

  Heading(0, "Block Quote")
  BlockQuote {
    Text("These paragraphs are quoted.")
    Text("More text.")
    BlockQuote {
      Text("Nested block quote.")
    }
  }

  Heading(0, "Table")
  Table(headerRow = {
    cell { Text("Column 1") }
    cell { Text("Column 2") }
  }) {
    row {
      cell { Text("Hello") }
      cell {
        CodeBlock("Foo bar")
      }
    }
    row {
      cell {
        BlockQuote {
          Text("Stuff")
        }
      }
      cell { Text("Hello world this is a really long line that is going to wrap hopefully") }
    }
  }
}

Looks like this:

printing

A library for using Compose to generated printed documents, using Android's printing services.

There are multiple entry points into this library. See their kdoc for usage and parameter documentation, and take a look at the samples for example code.

• Printable – This is the simplest entry point. It's a composable function that displays its content normally on screen, but can also print itself.
• ComposePrintAdapter – This is a PrintDocumentAdapter that can be used directly with Android's printing APIs to print any composable function.
• Paged – This is another composable, but doesn't actually have anything to do with printing. Conceptually it's similar to a ScrollableColumn – it lays its contents out at full height, then can display them at various vertical offsets. However, it also tries to ensure that no composables are clipped at the bottom, by measuring where all the leaf composables (those without any children) are located clipping the content before them. It is used by the printing APIs to try to ensure that composable content looks decent when split into printer pages.

Here's a sample that tries to match the style of one of the Google Docs templates. It looks great on small phone screens, but also prints: