fix: Add inline preview

frappe/public/js/print_format_builder/Preview.vue

@@ -0,0 +1,107 @@
+<template>
+	<div class="h-100">
+		<div class="row">
+			<div class="col">
+				<div ref="doc-select"></div>
+			</div>
+			<div class="col">
+				<div ref="preview-type"></div>
+			</div>
+			<div class="col d-flex">
+				<a v-if="url" class="btn btn-default btn-sm btn-new-tab" target="_blank" :href="url">
+					{{ __("Open in a new tab") }}
+				</a>
+			</div>
+		</div>
+		<div v-if="url && !preview_loaded">Generating preview...</div>
+		<iframe
+			:src="url"
+			v-if="url"
+			v-show="preview_loaded"
+			class="preview-iframe"
+			@load="preview_loaded = true"
+		></iframe>
+	</div>
+</template>
+<script>
+import { storeMixin } from "./store";
+export default {
+	name: "Preview",
+	mixins: [storeMixin],
+	data() {
+		return {
+			type: "PDF",
+			docname: null,
+			preview_loaded: false
+		};
+	},
+	mounted() {
+		this.doc_select = frappe.ui.form.make_control({
+			parent: this.$refs["doc-select"],
+			df: {
+				label: __("Select {0}", [__(this.doctype)]),
+				fieldname: "docname",
+				fieldtype: "Link",
+				options: this.doctype,
+				change: () => {
+					this.docname = this.doc_select.get_value();
+				}
+			},
+			render_input: true
+		});
+		this.preview_type = frappe.ui.form.make_control({
+			parent: this.$refs["preview-type"],
+			df: {
+				label: __("Preview type"),
+				fieldname: "docname",
+				fieldtype: "Select",
+				options: ["PDF", "HTML"],
+				change: () => {
+					this.type = this.preview_type.get_value();
+				}
+			},
+			render_input: true
+		});
+		this.preview_type.set_value(this.type);
+		this.get_default_docname().then(
+			docname => docname && this.doc_select.set_value(docname)
+		);
+	},
+	methods: {
+		get_default_docname() {
+			return frappe.db.get_list(this.doctype, { limit: 1 }).then(doc => {
+				return doc.length > 0 ? doc[0].name : null;
+			});
+		}
+	},
+	computed: {
+		doctype() {
+			return this.print_format.doc_type;
+		},
+		url() {
+			if (!this.docname) return null;
+			let params = new URLSearchParams();
+			params.append("doctype", this.doctype);
+			params.append("name", this.docname);
+			params.append("print_format", this.print_format.name);
+			let url =
+				this.type == "PDF"
+					? `/api/method/frappe.utils.weasyprint.download_pdf`
+					: "/printpreview";
+			return `${url}?${params.toString()}`;
+		}
+	}
+};
+</script>
+<style scoped>
+.preview-iframe {
+	width: 100%;
+	height: 96%;
+	border: none;
+	border-radius: var(--border-radius);
+}
+.btn-new-tab {
+    margin-top: auto;
+    margin-bottom: 1.2rem;
+}
+</style>

frappe/public/js/print_format_builder/PrintFormatBuilder.vue

@@ -4,13 +4,17 @@
 			<PrintFormatControls />
 		</div>
 		<div class="print-format-container col-9">
-			<PrintFormat />
+			<keep-alive>
+				<Preview v-if="show_preview" />
+				<PrintFormat v-else />
+			</keep-alive>
 		</div>
 	</div>
 </template>
 
 <script>
 import PrintFormat from "./PrintFormat.vue";
+import Preview from "./Preview.vue";
 import PrintFormatControls from "./PrintFormatControls.vue";
 import { getStore } from "./store";
 
@@ -19,7 +23,13 @@ export default {
 	props: ["print_format_name"],
 	components: {
 		PrintFormat,
-		PrintFormatControls
+		PrintFormatControls,
+		Preview
+	},
+	data() {
+		return {
+			show_preview: false
+		};
 	},
 	provide() {
 		return {
@@ -29,6 +39,11 @@ export default {
 	mounted() {
 		this.$store.fetch();
 	},
+	methods: {
+		toggle_preview() {
+			this.show_preview = !this.show_preview;
+		}
+	},
 	computed: {
 		$store() {
 			return getStore(this.print_format_name);

frappe/public/js/print_format_builder/print_format_builder.bundle.js

@@ -6,8 +6,8 @@ class PrintFormatBuilder {
 		this.page = page;
 		this.print_format = print_format;
 
-		this.page.clear_actions()
-		this.page.clear_custom_actions()
+		this.page.clear_actions();
+		this.page.clear_custom_actions();
 
 		this.page.set_title(__("Editing {0}", [this.print_format]));
 		this.page.set_primary_action(__("Save changes"), () => {
@@ -17,10 +17,8 @@ class PrintFormatBuilder {
 			this.$component.$store.reset_changes();
 		});
 		this.page.add_button(
-			__("Preview"),
-			() => {
-				this.preview();
-			},
+			__("Toggle Preview"),
+			() => this.$component.toggle_preview(),
 			{ icon: "small-file" }
 		);
 
@@ -35,46 +33,6 @@ class PrintFormatBuilder {
 		});
 		this.$component = $vm.$children[0];
 	}
-
-	async preview() {
-		let doctype = this.$component.$store.print_format.doc_type;
-		let default_doc = await frappe.db.get_list(doctype, {
-			limit: 1
-		});
-
-		let d = new frappe.ui.Dialog({
-			title: __("Preview Print Format"),
-			fields: [
-				{
-					label: __("Type"),
-					fieldname: "type",
-					fieldtype: "Select",
-					options: ["PDF", "HTML"],
-					default: "PDF"
-				},
-				{
-					label: __("Select Document"),
-					fieldname: "docname",
-					fieldtype: "Link",
-					options: doctype,
-					reqd: 1,
-					default: default_doc.length > 0 ? default_doc[0].name : null
-				}
-			],
-			primary_action: ({ docname, type }) => {
-				let params = new URLSearchParams();
-				params.append("doctype", doctype);
-				params.append("name", docname);
-				params.append("print_format", this.print_format);
-				let url =
-					type == "PDF"
-						? `/api/method/frappe.utils.weasyprint.download_pdf`
-						: "/printpreview";
-				window.open(`${url}?${params.toString()}`, "_blank");
-			}
-		});
-		d.show();
-	}
 }
 
 frappe.provide("frappe.ui");