Added defaultSelectedTab webpart property

Author: Ateina

src/controls/filePicker/FilePicker.tsx

@@ -455,7 +455,7 @@ export class FilePicker extends React.Component<
     props: IFilePickerProps,
     orgAssetsEnabled: boolean
   ): string => {
-    const tabConfig = [
+    const tabsConfig = [
       { isTabVisible: !props.hideRecentTab, tabKey: "keyRecent" },
       { isTabVisible: !props.hideStockImages, tabKey: "keyStockImages" },
       { isTabVisible: props.bingAPIKey && !props.hideWebSearchTab, tabKey: "keyWeb" },
@@ -467,9 +467,15 @@ export class FilePicker extends React.Component<
       { isTabVisible: !props.hideLocalMultipleUploadTab, tabKey: "keyMultipleUpload" }
     ];
 
-    const visibleTabs = tabConfig.filter(tab => tab.isTabVisible);
+    const visibleTabs = tabsConfig.filter(tab => tab.isTabVisible);
     const visibleTabKeys = visibleTabs.map(tab => tab.tabKey);
 
+    // If defaultSelectedTab is provided and is visible, then return tabKey
+    if(this.props.defaultSelectedTab ?? visibleTabKeys.includes(this.props.defaultSelectedTab)) {
+      return this.props.defaultSelectedTab;
+    }
+
+    // If no valid default tab is provided, find the first visible tab in the order
     if (this.props.tabOrder) {
       const visibleTabSet = new Set(visibleTabKeys);
       return this.tabOrder.find(key => visibleTabSet.has(key));

src/controls/filePicker/IFilePickerProps.ts

@@ -180,4 +180,10 @@ export interface IFilePickerProps {
    * default ["keyRecent", "keyStockImages", "keyWeb", "keyOrgAssets", "keyOneDrive", "keySite", "keyUpload", "keyLink", "keyMultipleUpload"]
    */
    tabOrder?: string[];
+  /**
+   * Specifies default selected tab
+   * One of the keys from tabOrder
+   * One of ["keyRecent", "keyStockImages", "keyWeb", "keyOrgAssets", "keyOneDrive", "keySite", "keyUpload", "keyLink", "keyMultipleUpload"]
+  */
+  defaultSelectedTab?: string;
 }