Not able to use Coil library in Android View project with mixed Java-Kotlin code

I am trying to use the Coil image loading library in an Android View project with mixed Java-Kotlin source code.

I am following this guide about how to use the library in Java:

https://coil-kt.github.io/coil/java_compatibility/

I have added the library to my gradle app file:

 implementation("io.coil-kt.coil3:coil:3.2.0")
 implementation("io.coil-kt.coil3:coil-network-okhttp:3.2.0")

However, the compiler raises an incompatible types error in the following Java code.

ImageRequest request = new ImageRequest.Builder(context)
    .data("https://example.com/image.jpg")
    .crossfade(true)
    .target(imageView)
    .build();
imageLoader.enqueue(request);

error: incompatible types: ImageView cannot be converted to Target .target(imageView)

and in the following one the compiler is not able to find any ImageLoaders at all

ImageRequest request = new ImageRequest.Builder(context)
    .data("https://example.com/image.jpg")
    .size(1080, 1920)
    .build();
Drawable drawable = ImageLoaders.executeBlocking(imageLoader, request).getImage().asDrawable(context.resources);

Am I missing anything? How can I use this library in Java?

Solution

After reading documentation, I think Coil 3.x no longer accepts a raw ImageView in .target(). Instead, you must wrap the ImageView in a Target.

Use ViewTarget (Coil's wrapper) in Java like this:

import coil.target.ViewTarget;  

ImageRequest request = new ImageRequest.Builder(context)     .data("https://example.com/image.jpg")     
.crossfade(true)     
.target(new ImageViewTarget(imageView))   
 .build();  
imageLoader.enqueue(request);

There’s no ImageLoaders.executeBlocking() method in Coil 3.x. Coil 3 moved to suspending functions, and Java cannot directly call suspend functions like execute.

To use execute in Java, you must bridge through Kotlin. Here's how you can do it:

Step 1: Create a Kotlin helper function and call this method from java/kotlin classes

// Kotlin
import android.content.Context
import coil.ImageLoader
import coil.request.ImageRequest
import coil.request.SuccessResult
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.runBlocking
import kotlinx.coroutines.withContext
import android.graphics.drawable.Drawable

fun loadImageBlocking(context: Context, imageLoader: ImageLoader, request: ImageRequest): Drawable? {
    return runBlocking {
        val result = imageLoader.execute(request)
        if (result is SuccessResult) {
            return@runBlocking result.drawable
        }
        return@runBlocking null
    }
}