SpannableStringParser: A Kotlin repository from annshsingh

In Android, to style our text we use Spans.
Spans are markup objects that can be applied to parts of the text.

It requires us to deal with the indexes of the text that we want to style.

val string = SpannableString("Text with a foreground color span")
string.setSpan(ForegroundColorSpan(Color.RED), 12, 28, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE)

But what if the text is dynamic and the styling of the text is also dynamic.
Now, dealing with indexes and styling becomes really difficult for us.

This is where SpannableStringParser helps us.
You can specify which text to style and how to style them inside the string itself, and use the spannify() extension function to style it.

val string = "Text with a { `foreground color` < color:#FF0000 /> } span".spannify()

This string can also come from a back-end server and if we wish to change the style of the text in future, the string can be easily changed from back-end and no front-end change will be required.

SpannableStringParser internally uses Spannable, which is more performant than Html.

Have a Look

1. Text having a property

"Hello { `SpannableStringParser` < color:#0000FF /> }"

2. Text having multiple properties

"Hello { `SpannableStringParser` < color:#0000FF ; text-decoration-line:underline /> }"

3. Text having multiple properties with multiple values

"Hello { `SpannableStringParser` < color:#0000FF ; text-decoration-line:underline|line-through /> }"

Usage

Syntax for "text" having a property

text_view.text = "{ `text` < property:value /> }".spannify()

Syntax for "text" having multiple properties

text_view.text = "{ `text` < property:value ; property:value /> }".spannify()

Syntax for "text" having multiple properties with multiple values

text_view.text = "{ `text` < property:value ; property:value|value /> }".spannify()

You can even add custom properties using the spanner method.

spanner { property, value ->
    when (property) {
        "sub-script" -> if (value == "true") {
            return@spanner SubscriptSpan()
        }
        "super-script" -> if (value == "true") {
            return@spanner SuperscriptSpan()
        }
    }
    return@spanner null
}

Supported Properties

`color`

The color property specifies the color of text.

Examples: color : #FF00FF , color : #00FF00FF

`text-decoration-line`

The text-decoration-line property sets the kind of text decoration to use (like underline, line-through).

Examples: text-decoration-line : underline , text-decoration-line : line-through

`font-size`

The font-size property sets the size of a font.

Examples: font-size : 12dp , font-size : 1.5em , font-size : 24px

`font-style`

The font-style property specifies the font style for a text.

Examples: font-style : italic

`font-weight`

The font-weight property sets how thick or thin characters in text should be displayed.

Examples: font-weight : bold

`more-properties-coming-soon`

You can add your custom properties using the spanner method.
But! If you want any property to be added in SpannableStringParser, feel free to open issues/pull requests.

Download

Add JitPack repository to your root build.gradle file

allprojects {
    repositories {
        maven { url 'https://jitpack.io' }
    }
}

Add the dependency to your app build.gradle file

dependencies {
    implementation 'com.github.hitanshu-dhawan:SpannableStringParser:1.0.0'
}

Licence

Copyright (c) 2019 Hitanshu Dhawan

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.

annshsingh/SpannableStringParser