1 files changed, 69 insertions, 0 deletions
diff --git a/devtools/client/shared/widgets/tooltip/RulePreviewTooltip.js b/devtools/client/shared/widgets/tooltip/RulePreviewTooltip.js
new file mode 100644
index 0000000000..87e089d604
--- /dev/null
+++ b/devtools/client/shared/widgets/tooltip/RulePreviewTooltip.js
@@ -0,0 +1,69 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+"use strict";
+
+const { LocalizationHelper } = require("resource://devtools/shared/l10n.js");
+const {
+  HTMLTooltip,
+} = require("resource://devtools/client/shared/widgets/tooltip/HTMLTooltip.js");
+
+const XHTML_NS = "http://www.w3.org/1999/xhtml";
+const L10N = new LocalizationHelper(
+  "devtools/client/locales/inspector.properties"
+);
+
+/**
+ * Tooltip displayed for when a CSS property is selected/highlighted.
+ * TODO: For now, the tooltip content only shows "No Associated Rule". In Bug 1528288,
+ * we will be implementing content for showing the source CSS rule.
+ */
+class RulePreviewTooltip {
+  constructor(doc) {
+    this.show = this.show.bind(this);
+    this.destroy = this.destroy.bind(this);
+
+    // Initialize tooltip structure.
+    this._tooltip = new HTMLTooltip(doc, {
+      type: "arrow",
+      consumeOutsideClicks: true,
+      useXulWrapper: true,
+    });
+
+    this.container = doc.createElementNS(XHTML_NS, "div");
+    this.container.className = "rule-preview-tooltip-container";
+
+    this.message = doc.createElementNS(XHTML_NS, "span");
+    this.message.className = "rule-preview-tooltip-message";
+    this.message.textContent = L10N.getStr(
+      "rulePreviewTooltip.noAssociatedRule"
+    );
+    this.container.appendChild(this.message);
+
+    // TODO: Implement structure for showing the source CSS rule.
+
+    this._tooltip.panel.innerHTML = "";
+    this._tooltip.panel.appendChild(this.container);
+    this._tooltip.setContentSize({ width: "auto", height: "auto" });
+  }
+
+  /**
+   * Shows the tooltip on a given element.
+   *
+   * @param  {Element} element
+   *         The target element to show the tooltip with.
+   */
+  show(element) {
+    element.addEventListener("mouseout", () => this._tooltip.hide());
+    this._tooltip.show(element);
+  }
+
+  destroy() {
+    this._tooltip.destroy();
+    this.container = null;
+    this.message = null;
+  }
+}
+
+module.exports = RulePreviewTooltip;