Add methods for managing selected items.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@tp/tp-table",
-  "version": "1.3.4",
+  "version": "1.4.0",
   "description": "",
   "main": "tp-table.js",
   "scripts": {

tp-table.js

@@ -327,6 +327,22 @@ export class TpTable extends DomQuery(LitElement) {
     }
   }
 
+  get scrollLeft() {
+    return this.$.virtualList.scrollLeft;
+  }
+
+  set scrollLeft(val) {
+    this.$.virtualList.scrollLeft = val;
+  }
+
+  get scrollTop() {
+    return this.$.virtualList.scrollTop;
+  }
+
+  set scrollTop(val) {
+    this.$.virtualList.scrollTop = val;
+  }
+
   _onScroll(e) {
     this.$.tableHeader.style.paddingRight = (this.$.virtualList.offsetWidth - this.$.virtualList.clientWidth) + 'px';
     this.$.tableHeader.scrollLeft = this.$.virtualList.scrollLeft;
@@ -506,6 +522,14 @@ export class TpTable extends DomQuery(LitElement) {
     this._selectionChanged();
   }
 
+  selectAll() {
+    this._selectAll();
+  }
+
+  clearSelection() {
+    this._selectNone();
+  }
+
   _selectAll() {
     this._selItems = new Map();
     this.items.forEach(item => {