fix(excel-exporter): resolve async timing issues with dynamic fflate import

Author: gedinakova

projects/igniteui-angular/grids/core/src/services/excel/excel-files.ts

@@ -8,45 +8,50 @@ import { yieldingLoop } from 'igniteui-angular/core';
  * @hidden
  */
 export class RootRelsFile implements IExcelFile {
-    public writeElement(folder: Object) {
-        import('fflate').then(({ strToU8 }) => folder['.rels'] = strToU8(ExcelStrings.getRels()));
+    public async writeElement(folder: Object): Promise<void> {
+        const { strToU8 } = await import('fflate');
+        folder['.rels'] = strToU8(ExcelStrings.getRels());
     }
 }
 
 /**
  * @hidden
  */
 export class AppFile implements IExcelFile {
-    public writeElement(folder: Object, worksheetData: WorksheetData) {
-        import('fflate').then(({ strToU8 }) => folder['app.xml'] = strToU8(ExcelStrings.getApp(worksheetData.options.worksheetName)));
+    public async writeElement(folder: Object, worksheetData: WorksheetData): Promise<void> {
+        const { strToU8 } = await import('fflate');
+        folder['app.xml'] = strToU8(ExcelStrings.getApp(worksheetData.options.worksheetName));
     }
 }
 
 /**
  * @hidden
  */
 export class CoreFile implements IExcelFile {
-    public writeElement(folder: Object) {
-        import('fflate').then(({ strToU8 }) => folder['core.xml'] = strToU8(ExcelStrings.getCore()));
+    public async writeElement(folder: Object): Promise<void> {
+        const { strToU8 } = await import('fflate');
+        folder['core.xml'] = strToU8(ExcelStrings.getCore());
     }
 }
 
 /**
  * @hidden
  */
 export class WorkbookRelsFile implements IExcelFile {
-    public writeElement(folder: Object, worksheetData: WorksheetData) {
+    public async writeElement(folder: Object, worksheetData: WorksheetData): Promise<void> {
         const hasSharedStrings = !worksheetData.isEmpty || worksheetData.options.alwaysExportHeaders;
-        import('fflate').then(({ strToU8 }) => folder['workbook.xml.rels'] = strToU8(ExcelStrings.getWorkbookRels(hasSharedStrings)));
+        const { strToU8 } = await import('fflate');
+        folder['workbook.xml.rels'] = strToU8(ExcelStrings.getWorkbookRels(hasSharedStrings));
     }
 }
 
 /**
  * @hidden
  */
 export class ThemeFile implements IExcelFile {
-    public writeElement(folder: Object) {
-        import('fflate').then(({ strToU8 }) => folder['theme1.xml'] = strToU8(ExcelStrings.getTheme()));
+    public async writeElement(folder: Object): Promise<void> {
+        const { strToU8 } = await import('fflate');
+        folder['theme1.xml'] = strToU8(ExcelStrings.getTheme());
     }
 }
 
@@ -716,35 +721,38 @@ export class WorksheetFile implements IExcelFile {
  * @hidden
  */
 export class StyleFile implements IExcelFile {
-    public writeElement(folder: Object) {
-        import('fflate').then(({ strToU8 }) => folder['styles.xml'] = strToU8(ExcelStrings.getStyles()));
+    public async writeElement(folder: Object): Promise<void> {
+        const { strToU8 } = await import('fflate');
+        folder['styles.xml'] = strToU8(ExcelStrings.getStyles());
     }
 }
 
 /**
  * @hidden
  */
 export class WorkbookFile implements IExcelFile {
-    public writeElement(folder: Object, worksheetData: WorksheetData) {
-        import('fflate').then(({ strToU8 }) => folder['workbook.xml'] = strToU8(ExcelStrings.getWorkbook(worksheetData.options.worksheetName)));
+    public async writeElement(folder: Object, worksheetData: WorksheetData): Promise<void> {
+        const { strToU8 } = await import('fflate');
+        folder['workbook.xml'] = strToU8(ExcelStrings.getWorkbook(worksheetData.options.worksheetName));
     }
 }
 
 /**
  * @hidden
  */
 export class ContentTypesFile implements IExcelFile {
-    public writeElement(folder: Object, worksheetData: WorksheetData) {
+    public async writeElement(folder: Object, worksheetData: WorksheetData): Promise<void> {
         const hasSharedStrings = !worksheetData.isEmpty || worksheetData.options.alwaysExportHeaders;
-        import('fflate').then(({ strToU8 }) => folder['[Content_Types].xml'] = strToU8(ExcelStrings.getContentTypesXML(hasSharedStrings, worksheetData.options.exportAsTable)));
+        const { strToU8 } = await import('fflate');
+        folder['[Content_Types].xml'] = strToU8(ExcelStrings.getContentTypesXML(hasSharedStrings, worksheetData.options.exportAsTable));
     }
 }
 
 /**
  * @hidden
  */
 export class SharedStringsFile implements IExcelFile {
-    public writeElement(folder: Object, worksheetData: WorksheetData) {
+    public async writeElement(folder: Object, worksheetData: WorksheetData): Promise<void> {
         const dict = worksheetData.dataDictionary;
         const sortedValues = dict.getKeys();
         const sharedStrings = new Array<string>(sortedValues.length);
@@ -753,21 +761,20 @@ export class SharedStringsFile implements IExcelFile {
             sharedStrings[dict.getSanitizedValue(value)] = '<si><t>' + value + '</t></si>';
         }
 
-        import('fflate').then(({ strToU8 }) => {
-            folder['sharedStrings.xml'] = strToU8(ExcelStrings.getSharedStringXML(
-                dict.stringsCount,
-                sortedValues.length,
-                sharedStrings.join(''))
-            );
-        });
+        const { strToU8 } = await import('fflate');
+        folder['sharedStrings.xml'] = strToU8(ExcelStrings.getSharedStringXML(
+            dict.stringsCount,
+            sortedValues.length,
+            sharedStrings.join(''))
+        );
     }
 }
 
 /**
  * @hidden
  */
 export class TablesFile implements IExcelFile {
-    public writeElement(folder: Object, worksheetData: WorksheetData) {
+    public async writeElement(folder: Object, worksheetData: WorksheetData): Promise<void> {
         const columnCount = worksheetData.columnCount;
         const lastColumn = ExcelStrings.getExcelColumn(columnCount - 1) + worksheetData.rowCount;
         const autoFilterDimension = 'A1:' + lastColumn;
@@ -800,15 +807,17 @@ export class TablesFile implements IExcelFile {
             sortString = `<sortState ref="A2:${lastColumn}"><sortCondition descending="${dir}" ref="${sc}1:${sc}15"/></sortState>`;
         }
 
-        import('fflate').then(({ strToU8 }) => folder['table1.xml'] = strToU8(ExcelStrings.getTablesXML(autoFilterDimension, tableDimension, tableColumns, sortString)));
+        const { strToU8 } = await import('fflate');
+        folder['table1.xml'] = strToU8(ExcelStrings.getTablesXML(autoFilterDimension, tableDimension, tableColumns, sortString));
     }
 }
 
 /**
  * @hidden
  */
 export class WorksheetRelsFile implements IExcelFile {
-    public writeElement(folder: Object) {
-        import('fflate').then(({ strToU8 }) => folder['sheet1.xml.rels'] = strToU8(ExcelStrings.getWorksheetRels()));
+    public async writeElement(folder: Object): Promise<void> {
+        const { strToU8 } = await import('fflate');
+        folder['sheet1.xml.rels'] = strToU8(ExcelStrings.getWorksheetRels());
     }
 }