Android Coil 3 extend ImageRequest‘s custom method/function，Kotlin

zhangphil2026-05-16 9:43

Android Coil 3 extend ImageRequest's custom method/function，Kotlin

为Android Coil3图像加载库扩展自定义超时功能。通过创建MyCoilMgr类，使用companion object定义timeout扩展函数和属性，并实现TimeoutInterceptor拦截器来监控请求耗时。拦截器使用withTimeoutOrNull协程函数处理超时逻辑，记录请求耗时或超时情况。最后展示了使用方式：通过ImageRequest.Builder.timeout()设置超时时间，并用MyCoilMgr实例执行请求。该方案为Coil3提供了灵活的超时控制能力。

Kotlin 复制代码

class MyCoilMgr {
    companion object {
     
        private val timeoutKey = Extras.Key(default = Long.MAX_VALUE)

        fun ImageRequest.Builder.timeout(timeout: Long) = apply {
            extras[timeoutKey] = timeout
        }

        val ImageRequest.timeout: Long
            get() = getExtra(timeoutKey)


        ...
    }

    
    fun init(ctx: Context): ImageLoader {

        //初始化加载器。
        mImageLoader = ImageLoader.Builder(ctx)
            ...
            .components {
                add(TimeoutInterceptor())
            }.build()

        return mImageLoader
    }
}

Kotlin 复制代码

import android.util.Log
import coil3.intercept.Interceptor
import coil3.request.ImageResult
import com.ppdemo.coil.MyCoilMgr.Companion.timeout
import kotlinx.coroutines.withTimeoutOrNull

class TimeoutInterceptor : Interceptor {
    companion object {
        const val TAG = "fly/TimeoutInterceptor"
    }

    var startTime = 0L
    var timeCost = 0L
    lateinit var result: ImageResult

    override suspend fun intercept(chain: Interceptor.Chain): ImageResult {
        val timeout = chain.request.timeout

        val exe = withTimeoutOrNull(timeout, {
            startTime = System.currentTimeMillis()
            result = chain.proceed()
            timeCost = System.currentTimeMillis() - startTime
        })

        if (exe == null) {
            Log.e(TAG, "timeout! $timeout ms , request=${chain.request.data}")
        } else {
            Log.d(TAG, "time cost = $timeCost ms , request=${chain.request.data}")
        }

        return result
    }
}

so, we can use it in ImageRequest, for example:

Kotlin 复制代码

        val req = ImageRequest.Builder(this)
            ....
            .timeout(1000)
            .build()
        MyCoilMgr.INSTANCE.enqueue(req)