Android TextView with inline images.

README.md

Usage

Replace com.example with your package name.

<com.example.ImageSpannedTextView
        android:id="@+id/text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/image_text"/>

Replace ic_span with your drawable resource image name. Here ic_span is a ic_span.png file.

<string name="image_text">This is [img src=ic_span/] an inline image</string>

ImageSpannedTextView.kt

import android.content.Context
import android.text.Spannable
import android.text.style.ImageSpan
import android.util.AttributeSet
import androidx.appcompat.widget.AppCompatTextView
import java.util.regex.Matcher
import java.util.regex.Pattern

class ImageSpannedTextView : AppCompatTextView {
    constructor(
        context: Context,
        attrs: AttributeSet?,
        defStyle: Int
    ) : super(context, attrs, defStyle)

    constructor(context: Context, attrs: AttributeSet?) : super(context, attrs)

    constructor(context: Context) : super(context)

    override fun setText(text: CharSequence, type: BufferType?) {
        val s = getTextWithImages(context, text)
        super.setText(s, BufferType.SPANNABLE)
    }

    private fun addImages(context: Context, spannable: Spannable): Boolean {
        val refImg: Pattern = Pattern.compile("\\Q[img src=\\E([a-zA-Z0-9_]+?)\\Q/]\\E")
        var hasChanges = false
        val matcher: Matcher = refImg.matcher(spannable)
        while (matcher.find()) {
            var set = true
            for (span in spannable.getSpans(
                matcher.start(),
                matcher.end(),
                ImageSpan::class.java
            )) {
                if (spannable.getSpanStart(span) >= matcher.start()
                    && spannable.getSpanEnd(span) <= matcher.end()
                ) {
                    spannable.removeSpan(span)
                } else {
                    set = false
                    break
                }
            }
            val res =
                spannable.subSequence(matcher.start(1), matcher.end(1)).toString()
                    .trim { it <= ' ' }
            val id: Int =
                context.resources.getIdentifier(res, "drawable", context.packageName)
            if (set) {
                hasChanges = true
                spannable.setSpan(
                    ImageSpan(context, id),
                    matcher.start(),
                    matcher.end(),
                    Spannable.SPAN_EXCLUSIVE_EXCLUSIVE
                )
            }
        }
        return hasChanges
    }

    private fun getTextWithImages(context: Context, text: CharSequence): Spannable {
        val spannable = spannableFactory.newSpannable(text)
        addImages(context, spannable)
        return spannable
    }

    companion object {
        val spannableFactory = Spannable.Factory.getInstance()
    }
}