Style sheet storage

Style sheets are part of SimplyHTML since stage 1 of the application. Since then they were only saved along with a document with a set of static styles. With stage 8 of SimplyHTML manipulation of named styles is supported so that the original style sheet handling needs to be extended.

Loading style sheets

Class DocumentPane now has two ways of creating a document with respect to style sheets. A new document is created with the underlying EditorKit creating a default style sheet from the resources package of SimplyHTML (as done in previous stages).

This is not longer done when an existing document is loaded. In such case the underlying EditorKit creates a default document without a default style sheet. Class DocumentPane instead looks for the style sheet reference inside this document and loads this style sheet for the particular document instead.

The EditorKit not longer shares a single style sheet among different documents, each document has associated its own style sheet.

Saving style sheets

When a style sheet is saved, four cases are now handled

1. no styles are present at save location, create new style sheet
2. the style sheet was loaded from somewhere else and now is being saved at a new location where a style sheet exists havig the same name
3. the style sheet is saved at the same location where it was loaded from
4. the style sheet was newly created and now is being saved at a location where a style sheet exists havig the same name

In case 2 and 4 above, the style sheets are merged overwriting existing styles in the found style sheet with styles from the saved style sheet. Styles from the found style sheet not existing in the saved style sheet are kept in the newly saved style sheet.

In case 3 above the existing style sheet is overwritten by the new version.

Tradeoffs

While above save strategy does not require user interaction other than to choose a save loaction and name for the respective document (as before) it still leaves the problem that an existing style sheet with the same name could have styles with the same name as altered ones in the saved style sheet. Overwriting such styles could cause unwanted styles to appear in other documents sharing the particular style sheet.

Therefore the user is obliged to either

1. not save documents in the same directory when they do not share the same set of named styles or
2. use different style names for different styles over all documents sharing the same style sheet