Add download button to selected images in Gallery (#5025)

* add download button to gallery selected images

* add changeset

* add story

* tweak

* fix href val for internal file paths

* set show_download_button to True by default

* lint backend

---------

Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>

.changeset/curly-nights-yawn.md

@@ -0,0 +1,7 @@
+---
+"@gradio/app": minor
+"@gradio/gallery": minor
+"gradio": minor
+---
+
+feat:Add download button to selected images in `Gallery`

gradio/components/gallery.py

@@ -54,6 +54,7 @@ def __init__(
         | None = None,
         allow_preview: bool = True,
         show_share_button: bool | None = None,
+        show_download_button: bool | None = True,
         **kwargs,
     ):
         """
@@ -75,13 +76,20 @@ def __init__(
             object_fit: CSS object-fit property for the thumbnail images in the gallery. Can be "contain", "cover", "fill", "none", or "scale-down".
             allow_preview: If True, images in the gallery will be enlarged when they are clicked. Default is True.
             show_share_button: If True, will show a share icon in the corner of the component that allows user to share outputs to Hugging Face Spaces Discussions. If False, icon does not appear. If set to None (default behavior), then the icon appears if this Gradio app is launched on Spaces, but not otherwise.
+            show_download_button: If True, will show a download button in the corner of the selected image. If False, the icon does not appear. Default is True.
+
         """
         self.grid_cols = columns
         self.grid_rows = rows
         self.height = height
         self.preview = preview
         self.object_fit = object_fit
         self.allow_preview = allow_preview
+        self.show_download_button = (
+            (utils.get_space() is not None)
+            if show_download_button is None
+            else show_download_button
+        )
         self.select: EventListenerMethod
         """
         Event listener for when the user selects image within Gallery.
@@ -125,6 +133,7 @@ def update(
         | None = None,
         allow_preview: bool | None = None,
         show_share_button: bool | None = None,
+        show_download_button: bool | None = None,
     ):
         updated_config = {
             "label": label,
@@ -141,6 +150,7 @@ def update(
             "object_fit": object_fit,
             "allow_preview": allow_preview,
             "show_share_button": show_share_button,
+            "show_download_button": show_download_button,
             "__type__": "update",
         }
         return updated_config
@@ -155,6 +165,7 @@ def get_config(self):
             "object_fit": self.object_fit,
             "allow_preview": self.allow_preview,
             "show_share_button": self.show_share_button,
+            "show_download_button": self.show_download_button,
             **IOComponent.get_config(self),
         }
 

js/app/src/components/Gallery/Gallery.stories.svelte

@@ -196,3 +196,16 @@
 		],
 	}}
 />
+
+<Story
+	name="Gallery with download button"
+	args={{
+		label: "My Cheetah Gallery",
+		grid_rows: 2,
+		height: 400,
+		show_download_button: true,
+		value: [
+			"https://gradio-builds.s3.amazonaws.com/demo-files/cheetah-002.jpg",
+		],
+	}}
+/>

js/app/src/components/Gallery/Gallery.svelte

@@ -26,6 +26,7 @@
 	export let object_fit: "contain" | "cover" | "fill" | "none" | "scale-down" =
 		"cover";
 	export let show_share_button = false;
+	export let show_download_button = false;
 </script>
 
 <Block
@@ -57,5 +58,6 @@
 		{object_fit}
 		{allow_preview}
 		{show_share_button}
+		{show_download_button}
 	/>
 </Block>

js/gallery/src/Gallery.svelte

@@ -6,10 +6,11 @@
 	import { createEventDispatcher } from "svelte";
 	import { tick } from "svelte";
 
-	import { Image } from "@gradio/icons";
+	import { Download, Image } from "@gradio/icons";
 	import type { FileData } from "@gradio/upload";
 	import { normalise_file } from "@gradio/upload";
 	import { format_gallery_for_sharing } from "./utils";
+	import { IconButton } from "@gradio/atoms";
 
 	export let show_label = true;
 	export let label: string;
@@ -25,6 +26,7 @@
 	export let object_fit: "contain" | "cover" | "fill" | "none" | "scale-down" =
 		"cover";
 	export let show_share_button = false;
+	export let show_download_button = false;
 
 	const dispatch = createEventDispatcher<{
 		select: SelectData;
@@ -105,6 +107,19 @@
 		}
 	}
 
+	function isFileData(obj: any): obj is FileData {
+		return typeof obj === "object" && obj !== null && "data" in obj;
+	}
+
+	function getHrefValue(selected: any): string {
+		if (isFileData(selected)) {
+			return selected.data;
+		} else if (typeof selected === "string") {
+			return selected;
+		}
+		return "";
+	}
+
 	$: {
 		if (selected_image !== old_selected_image) {
 			old_selected_image = selected_image;
@@ -163,8 +178,22 @@
 	{#if selected_image !== null && allow_preview}
 		<!-- svelte-ignore a11y-no-static-element-interactions -->
 		<div on:keydown={on_keydown} class="preview">
-			<ModifyUpload on:clear={() => (selected_image = null)} />
-
+			<div class="icon-buttons">
+				{#if show_download_button}
+					<a
+						href={getHrefValue(value[selected_image])}
+						target={window.__is_colab__ ? "_blank" : null}
+						download="image"
+					>
+						<IconButton Icon={Download} label="Download" />
+					</a>
+				{/if}
+
+				<ModifyUpload
+					absolute={false}
+					on:clear={() => (selected_image = null)}
+				/>
+			</div>
 			<!-- svelte-ignore a11y-click-events-have-key-events -->
 			<!-- svelte-ignore a11y-no-noninteractive-element-interactions -->
 			<img
@@ -399,4 +428,14 @@
 		right: 0px;
 		z-index: var(--layer-1);
 	}
+
+	.icon-buttons {
+		display: flex;
+		position: absolute;
+		right: 0;
+	}
+
+	.icon-buttons a {
+		margin: var(--size-1) 0;
+	}
 </style>