From Apache OpenOffice Wiki
Jump to: navigation, search

Text frames, text sections and page styles can be formatted to have columns. The width of columns is relative since the absolute width of the object is unknown in the model. The layout formatting is responsible for calculating the actual widths of the columns.

Columns are applied using the property TextColumns. It expects a service that has to be created by the document factory. The interface refines the characteristics of the text columns before applying the created TextColumns service to the property TextColumns.

Consider the following example to see how to work with text columns:

 /** This method demonstrates the XTextColumns interface and how to insert a blank paragraph
     using the XRelativeTextContentInsert interface
 protected void TextColumnsExample() {
     try {
         // Go to the end of the doucment
         // insert a new paragraph
         mxDocText.insertControlCharacter(mxDocCursor, ControlCharacter.PARAGRAPH_BREAK, false);
         // insert the string 'I am a fish.' 100 times
         for (int i = 0 ; i < 100 ; ++i) {
             mxDocText.insertString(mxDocCursor, "I am a fish.", false);
         // insert a paragraph break after the text
         mxDocText.insertControlCharacter(mxDocCursor, ControlCharacter.PARAGRAPH_BREAK, false);
         // Get the XParagraphCursor interface of our text cursor
         XParagraphCursor xParaCursor = (XParagraphCursor) UnoRuntime.queryInterface(
             XParagraphCursor.class, mxDocCursor);
         // Jump back before all the text we just inserted
         // Insert a string at the beginning of the block of text
         mxDocText.insertString(mxDocCursor, "Fish section begins:", false);
         // Then select all of the text
         // Create a new text section and get it's XNamed interface
         XNamed xSectionNamed = (XNamed) UnoRuntime.queryInterface(
             XNamed.class, mxDocFactory.createInstance(""));
         // Set the name of our new section (appropiately) to 'Fish'
         // Create the TextColumns service and get it's XTextColumns interface
         XTextColumns xColumns = (XTextColumns) UnoRuntime.queryInterface(
             XTextColumns.class, mxDocFactory.createInstance(""));
         // We want three columns
         xColumns.setColumnCount((short) 3);
         // Get the TextColumns, and make the middle one narrow with a larger margin
         // on the left than the right
         TextColumn[] aSequence = xColumns.getColumns ();
         aSequence[1].Width /= 2;
         aSequence[1].LeftMargin = 350;
         aSequence[1].RightMargin = 200;
         // Set the updated TextColumns back to the XTextColumns
         // Get the property set interface of our 'Fish' section
         XPropertySet xSectionProps = (XPropertySet) UnoRuntime.queryInterface(
             XPropertySet.class, xSectionNamed);
         // Set the columns to the Text Section
         xSectionProps.setPropertyValue("TextColumns", xColumns);
         // Get the XTextContent interface of our 'Fish' section
         mxFishSection = (XTextContent) UnoRuntime.queryInterface(
             XTextContent.class, xSectionNamed);
         // Insert the 'Fish' section over the currently selected text
         mxDocText.insertTextContent(mxDocCursor, mxFishSection, true);
         // Get the wonderful XRelativeTextContentInsert interface
         XRelativeTextContentInsert xRelative = (XRelativeTextContentInsert)
             UnoRuntime.queryInterface(XRelativeTextContentInsert.class, mxDocText);
         // Create a new empty paragraph and get it's XTextContent interface
         XTextContent xNewPara = (XTextContent) UnoRuntime.queryInterface(XTextContent.class, 
         // Insert the empty paragraph after the fish Text Section
         xRelative.insertTextContentAfter(xNewPara, mxFishSection);
     } catch (Exception e) {

The text columns property consists of structs. The Width elements of all structs in the TextColumns sequence make up a sum, that is provided by the method getReferenceValue() of the XTextColumns interface. To determine the metric width of an actual column, the reference value and the columns width element have to be calculated using the metric width of the object (page, text frame, text section) and a rule of three, for example:

 nColumn3Width = aColumns[3].Width / xTextColumns.getReferenceValue() * RealObjectWidth

The column margins (LeftMargin, and RightMargin elements of the struct) are inside of the column. Their values do not influence the column width. They just limit the space available for the column content.

The default column setting in creates columns with equal margins at inner columns, and no left margin at the leftmost column and no right margin at the rightmost column. Therefore, the relative width of the first and last column is smaller than those of the inner columns. This causes a limitation of this property: Setting the text columns with equal column content widths and equal margins is only possible when the width of the object (text frame, text section) can be determined. Unfortunately this is impossible when the width of the object depends on its environment itself.

Content on this page is licensed under the Public Documentation License (PDL).
Personal tools
In other languages