Custom Html.ImageGetter to load images in TextView HTML tags using Glide

GlideImageGetter.kt

/*
 * Based on java code by Yaser Rajabi https://gist.github.com/yrajabi
 */
package org.dailyislam.android.utils.extenstions

import android.graphics.Bitmap
import android.graphics.Canvas
import android.graphics.drawable.BitmapDrawable
import android.graphics.drawable.Drawable
import android.text.Html.ImageGetter
import android.widget.TextView
import com.bumptech.glide.Glide
import com.bumptech.glide.request.Request
import com.bumptech.glide.request.target.SizeReadyCallback
import com.bumptech.glide.request.target.Target
import com.bumptech.glide.request.transition.Transition
import java.lang.ref.WeakReference

class GlideImageGetter(
    textView: TextView,
    private val matchParentWidth: Boolean = false,
    densityAware: Boolean = false,
    private val imagesHandler: HtmlImagesHandler? = null
) : ImageGetter {
    private val container: WeakReference<TextView> = WeakReference(textView)
    private var density = 1.0f

    init {
        if (densityAware) {
            container.get()?.let {
                density = it.resources.displayMetrics.density
            }
        }
    }

    override fun getDrawable(source: String): Drawable {
        imagesHandler?.addImage(source)

        val drawable = BitmapDrawablePlaceholder()

        // Load Image to the Drawable
        container.get()?.apply {
            post {
                Glide.with(context)
                    .asBitmap()
                    .load(source)
                    .into(drawable)
            }
        }

        return drawable
    }

    private inner class BitmapDrawablePlaceholder : BitmapDrawable(container.get()?.resources, Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888)), Target<Bitmap> {
        private var drawable: Drawable? = null
            set(value) {
                field = value
                value?.let { drawable ->
                    val drawableWidth = (drawable.intrinsicWidth * density).toInt()
                    val drawableHeight = (drawable.intrinsicHeight * density).toInt()
                    val maxWidth = container.get()!!.measuredWidth
                    if (drawableWidth > maxWidth || matchParentWidth) {
                        val calculatedHeight = maxWidth * drawableHeight / drawableWidth
                        drawable.setBounds(0, 0, maxWidth, calculatedHeight)
                        setBounds(0, 0, maxWidth, calculatedHeight)
                    } else {
                        drawable.setBounds(0, 0, drawableWidth, drawableHeight)
                        setBounds(0, 0, drawableWidth, drawableHeight)
                    }
                    container.get()?.text = container.get()?.text
                }
            }

        override fun draw(canvas: Canvas) {
            drawable?.draw(canvas)
        }

        override fun onLoadStarted(placeholderDrawable: Drawable?) {
            placeholderDrawable?.let {
                drawable = it
            }
        }

        override fun onLoadFailed(errorDrawable: Drawable?) {
            errorDrawable?.let {
                drawable = it
            }
        }

        override fun onResourceReady(bitmap: Bitmap, transition: Transition<in Bitmap>?) {
            drawable = BitmapDrawable(container.get()!!.resources, bitmap)
        }

        override fun onLoadCleared(placeholderDrawable: Drawable?) {
            placeholderDrawable?.let {
                drawable = it
            }
        }

        override fun getSize(sizeReadyCallback: SizeReadyCallback) {
            sizeReadyCallback.onSizeReady(Target.SIZE_ORIGINAL, Target.SIZE_ORIGINAL)
        }

        override fun removeCallback(cb: SizeReadyCallback) {}
        override fun setRequest(request: Request?) {}
        override fun getRequest(): Request? {
            return null
        }

        override fun onStart() {}
        override fun onStop() {}
        override fun onDestroy() {}
    }

    interface HtmlImagesHandler {
        fun addImage(uri: String?)
    }
}

Thanks for writing this. Very helpful

You're Welcome 😊.

@iamriajul Svg format not supported. glide throwing error.

@iamriajul Svg format not supported. glide throwing error.

You may need to use SvgDrawableTranscoder
Check the Issue here: bumptech/glide#1239

@iamriajul
Hi, I am newly using this ImageGetter. My images within HTML shown in textview cannot display in the format of their correct sizes.
Could you offer a solution to display different sizes of images within HTML in TextView? Thanksss!!