Added keep-together paragraph style

README.md

@@ -40,6 +40,7 @@ style1.setTypeface(simpleOdf.Typeface.Bold);
 // paragraph formatting
 style1.setHorizontalAlignment(simpleOdf.HorizontalAlignment.Center);
 style1.setPageBreakBefore();
+style1.setKeepTogether();
 p1.setStyle(style1);
 // font usage
 document.declareFont("Open Sans", "Open Sans", simpleOdf.FontPitch.Variable);

src/OdfAttributeName.ts

@@ -1,5 +1,6 @@
 export enum OdfAttributeName {
   FormatBreakBefore = "fo:break-before",
+  FormatKeepTogether = "fo:keep-together",
   FormatColor = "fo:color",
   FormatFontSize = "fo:font-size",
   FormatFontStyle = "fo:font-style",

src/style/IParagraphProperties.ts

@@ -31,6 +31,13 @@ export interface IParagraphProperties {
    */
   setPageBreakBefore(): void;
 
+  /**
+   * Keeps paragraph lines on the same page (page break before paragraph if necessary).
+   *
+   * @since 0.6.0
+   */
+  setKeepTogether(keepTogether?: boolean): void;
+
   /**
    * Adds a new tab stop to this style.
    * If a tab stop at the same position already exists, the new tab stop will not be added.

src/style/ParagraphProperties.ts

@@ -7,6 +7,7 @@ import { TabStopType } from "./TabStopType";
 
 const DEFAULT_HORIZONTAL_ALIGNMENT = HorizontalAlignment.Default;
 const DEFAULT_PAGE_BREAK = false;
+const DEFAULT_KEEP_TOGETHER = false;
 
 /**
  * This class represents the style of a paragraph.
@@ -16,6 +17,7 @@ const DEFAULT_PAGE_BREAK = false;
 export class ParagraphProperties implements IParagraphProperties {
   private horizontalAlignment: HorizontalAlignment;
   private shouldBreakPageBefore: boolean;
+  private shouldKeepTogether: boolean;
   private tabStops: TabStop[] = [];
 
   /**
@@ -24,6 +26,7 @@ export class ParagraphProperties implements IParagraphProperties {
   public constructor() {
     this.horizontalAlignment = DEFAULT_HORIZONTAL_ALIGNMENT;
     this.shouldBreakPageBefore = DEFAULT_PAGE_BREAK;
+    this.shouldKeepTogether = DEFAULT_KEEP_TOGETHER;
   }
 
   /** @inheritDoc */
@@ -41,6 +44,11 @@ export class ParagraphProperties implements IParagraphProperties {
     this.shouldBreakPageBefore = true;
   }
 
+  /** @inheritDoc */
+  public setKeepTogether(keepTogether: boolean = true): void {
+    this.shouldKeepTogether = keepTogether;
+  }
+
   /** @inheritDoc */
   public addTabStop(position: number, type: TabStopType): TabStop | undefined;
 
@@ -80,9 +88,12 @@ export class ParagraphProperties implements IParagraphProperties {
    * @since 0.1.0
    */
   public isDefault(): boolean {
-    return this.horizontalAlignment === DEFAULT_HORIZONTAL_ALIGNMENT
-      && this.shouldBreakPageBefore === DEFAULT_PAGE_BREAK
-      && this.tabStops.length === 0;
+    return (
+      this.horizontalAlignment === DEFAULT_HORIZONTAL_ALIGNMENT &&
+      this.shouldBreakPageBefore === DEFAULT_PAGE_BREAK &&
+      this.shouldKeepTogether === DEFAULT_KEEP_TOGETHER &&
+      this.tabStops.length === 0
+    );
   }
 
   /**
@@ -102,13 +113,14 @@ export class ParagraphProperties implements IParagraphProperties {
 
     this.setHorizontalAlignmentAttribute(paragraphPropertiesElement);
     this.setPageBreakAttribute(paragraphPropertiesElement);
+    this.setKeepTogetherAttribute(paragraphPropertiesElement);
     this.setTabStopElements(document, paragraphPropertiesElement);
   }
 
   /**
    * Sets the `text-align` attribute if an horizontal alignment is set.
    *
-   * @param {Element} textPropertiesElement The element which will take the attribute
+   * @param {Element} paragraphPropertiesElement The element which will take the attribute
    */
   private setHorizontalAlignmentAttribute(paragraphPropertiesElement: Element): void {
     if (this.horizontalAlignment !== HorizontalAlignment.Default) {
@@ -119,19 +131,30 @@ export class ParagraphProperties implements IParagraphProperties {
   /**
    * Sets the page break attribute if a page break is set.
    *
-   * @param {Element} textPropertiesElement The element which will take the attribute
+   * @param {Element} paragraphPropertiesElement The element which will take the attribute
    */
   private setPageBreakAttribute(paragraphPropertiesElement: Element): void {
     if (this.shouldBreakPageBefore === true) {
       paragraphPropertiesElement.setAttribute(OdfAttributeName.FormatBreakBefore, "page");
     }
   }
 
+  /**
+   * Sets the keep together attribute if paragraph marked as keep together.
+   *
+   * @param {Element} paragraphPropertiesElement The element which will take the attribute
+   */
+  private setKeepTogetherAttribute(paragraphPropertiesElement: Element): void {
+    if (this.shouldKeepTogether === true) {
+      paragraphPropertiesElement.setAttribute(OdfAttributeName.FormatKeepTogether, "always");
+    }
+  }
+
   /**
    * Adds the `tab-stops` element and the tab stop definitions if any tab stop is set.
    *
    * @param {Document} document The XML document
-   * @param {Element} textPropertiesElement The element which will be used as parent
+   * @param {Element} paragraphPropertiesElement The element which will be used as parent
    */
   private setTabStopElements(document: Document, paragraphPropertiesElement: Element): void {
     if (this.tabStops.length === 0) {

src/style/ParagraphStyle.ts

@@ -94,6 +94,11 @@ export class ParagraphStyle implements IParagraphStyle {
     return this.paragraphProperties.setPageBreakBefore();
   }
 
+  /** @inheritDoc */
+  public setKeepTogether(keepTogether: boolean = true): void {
+    return this.paragraphProperties.setKeepTogether(keepTogether);
+  }
+
   /** @inheritDoc */
   public addTabStop(position: number, type: TabStopType): TabStop | undefined;
   /** @inheritDoc */
@@ -143,6 +148,7 @@ export class ParagraphStyle implements IParagraphStyle {
     // paragraph properties
     hash.update(this.paragraphProperties.getHorizontalAlignment());
     hash.update((this.paragraphProperties as any).shouldBreakPageBefore ? "pb" : "");
+    hash.update((this.paragraphProperties as any).shouldKeepTogether ? "kt" : "");
     this.paragraphProperties.getTabStops().forEach((tabStop: TabStop) => {
       hash.update(`${tabStop.getPosition()}${tabStop.getType()}`);
     });

test/integration.spec.ts

@@ -54,6 +54,12 @@ xdescribe("integration", () => {
       heading.getStyle().setPageBreakBefore();
     });
 
+    it("keep together", () => {
+      const heading = document.addParagraph("Paragraph Formatting");
+      heading.setStyle(new ParagraphStyle());
+      heading.getStyle().setKeepTogether();
+    });
+
     it("align text", () => {
       const paragraph = document.addParagraph("Some centered text");
       paragraph.setStyle(new ParagraphStyle());

test/style/ParagraphProperties.spec.ts

@@ -34,6 +34,8 @@ describe(ParagraphProperties.name, () => {
 
   // setPageBreakBefore
 
+  // setKeepTogether
+
   describe("#addTabStop", () => {
     it("add new item to the list of tab stops by position and return the added tab stop", () => {
       const testTabStop = new TabStop(23);
@@ -118,6 +120,12 @@ describe(ParagraphProperties.name, () => {
       expect(properties.isDefault()).toBe(false);
     });
 
+    it("return false if keep together was set", () => {
+      properties.setKeepTogether();
+
+      expect(properties.isDefault()).toBe(false);
+    });
+
     it("return false if a tab stop was set", () => {
       properties.addTabStop(23, TabStopType.Right);