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SVG¶

要添加SVG支持, 需要引入扩展库:

implementation("io.coil-kt:coil-svg:2.2.0")

并且在构建ImageLoader的时候在组件注册中添加解码器:

val imageLoader = ImageLoader.Builder(context)
    .components {
        add(SvgDecoder.Factory())
    }
    .build()

ImageLoader将自动地探测并解码任何SVG文件. Coil通过在文件的前1KB中查找<svg标记来探测SVG文件, 这应该能覆盖大多数场景. 如果SVG没能自动探测, 可以给该请求显式地设置Decoder给SvgDecoder.

Video Frame¶

要添加视频帧支持, 需要引入扩展库:

implementation("io.coil-kt:coil-video:2.2.0")

并且在构建ImageLoader的时候在组件注册中添加解码器:

val imageLoader = ImageLoader.Builder(context)
    .components {
        add(VideoFrameDecoder.Factory())
    }
    .build()

如果想指定该帧的时间码从视频中解析, 需要使用videoFrameMillis或者videoFrameMicros:

imageView.load(File("/path/to/video.mp4")) {
    videoFrameMillis(1000)
}

如果帧时间没有指定, 视频首帧将被解析.

ImageLoader能够自动地探测任何视频并解析帧, 但前提是请求的文件名/URI以合法地视频扩展结尾. 如果没有的话, 需要给请求显式地设置Decoder.

从Glide/Picasso中迁移¶

下面是一些例子展示了如何从Glide/Picasso调用迁移到Coil调用:

基础用法¶

// Glide
Glide.with(context)
    .load(url)
    .into(imageView)

// Picasso
Picasso.get()
    .load(url)
    .into(imageView)

// Coil
imageView.load(url)

自定义请求¶

imageView.scaleType = ImageView.ScaleType.FIT_CENTER

// Glide
Glide.with(context)
    .load(url)
    .placeholder(placeholder)
    .fitCenter()
    .into(imageView)

// Picasso
Picasso.get()
    .load(url)
    .placeholder(placeholder)
    .fit()
    .into(imageView)

// Coil (automatically detects the scale type)
imageView.load(url) {
    placeholder(placeholder)
}

非View目标¶

// Glide (has optional callbacks for start and error)
Glide.with(context)
    .load(url)
    .into(object : CustomTarget<Drawable>() {
        override fun onResourceReady(resource: Drawable, transition: Transition<Drawable>) {
            // Handle the successful result.
        }

        override fun onLoadCleared(placeholder: Drawable) {
            // Remove the drawable provided in onResourceReady from any Views and ensure no references to it remain.
        }
    })

// Picasso
Picasso.get()
    .load(url)
    .into(object : BitmapTarget {
        override fun onBitmapLoaded(bitmap: Bitmap, from: Picasso.LoadedFrom) {
            // Handle the successful result.
        }

        override fun onBitmapFailed(e: Exception, errorDrawable: Drawable?) {
            // Handle the error drawable.
        }

        override fun onPrepareLoad(placeHolderDrawable: Drawable?) {
            // Handle the placeholder drawable.
        }
    })

// Coil
val request = ImageRequest.Builder(context)
    .data(url)
    .target(
        onStart = { placeholder ->
            // Handle the placeholder drawable.
        },
        onSuccess = { result ->
            // Handle the successful result.
        },
        onError = { error ->
            // Handle the error drawable.
        }
    )
    .build()
context.imageLoader.enqueue(request)

后台线程¶

// Glide (blocks the current thread; must not be called from the main thread)
val drawable = Glide.with(context)
    .load(url)
    .submit(width, height)
    .get()

// Picasso (blocks the current thread; must not be called from the main thread)
val drawable = Picasso.get()
    .load(url)
    .resize(width, height)
    .get()

// Coil (suspends the current coroutine; non-blocking and thread safe)
val request = ImageRequest.Builder(context)
    .data(url)
    .size(width, height)
    .build()
val drawable = context.imageLoader.execute(request).drawable