# File Associations

### Introduction

One of the most convenient aspects of &kde;, is its ability to automatically match a data file, with its application. As an example, when you click on your favourite &kword; document in &konqueror;, &kde; automatically starts &kword;, and automatically loads that file into &kword; so you can begin working on it.

In the example above, the &kword; Data file is associated with &kword; (the application). These file associations are crucial to the functioning of &kde;.

When &kde; is installed, it automatically creates hundreds of file associations to many of the most common data types. These initial associations are based on the most commonly included software, and the most common user preferences.

Unfortunately, &kde; can not:

- predict every possible combination of software and data files

- prepare for file formats not yet invented

- or predict everyone's favourite application for certain file formats

You can change your current file associations or add new file associations using this module.

Each file association is recorded as a mime type. &MIME; stands for Multipurpose Internet Mail Extensions. It allows a computer to determine the type of file, without opening and analysing the format of each and every file.

### How to use this module

The file associations are organised into several categories, and at a minimum you will have:

1. Application

2. Audio

3. Image

4. Inode

5. Message

6. Multipart

7. Print

8. Text

9. Video

All of the file associations are sorted into one of these categories.

There is also an overview category All, which displays all the file types in one list, without categorising them.

There is no functional difference between any of the categories. These categories are designed to help organise your file associations, but they do not alter the associations in any way.

The categories are listed in the box labelled Known Types.

You can explore each of these categories, and see the file associations contained within each one, by simply double-clicking on the category name. You will be presented with a list of the associated mime-types under that category.

You can also search for a particular &MIME; type by using the search box. The search box is labelled Find filename pattern and is located above the category list.

Simply type the first letter of the &MIME; type you are interested in. The categories are automatically expanded, and only the mime-types that include that letter are displayed.

You can then enter a second character and the mime-types will be further limited to mime types containing those two characters.

#### Adding a new mime type

If you want to add a new &MIME; type to your file associations, you can click on the Add... button. A small dialogue box will appear. You select the category from the drop down box, and type the &MIME; name in the blank labelled Type name. Click OK to add the new mime type, or click Cancel to not add any new mime-types.

#### Removing a mime type

If you want to remove a &MIME; type, simply select the &MIME; type you want to delete by clicking once with the mouse on the &MIME; type name. Then click the button labelled Remove. The &MIME; type will be deleted immediately.

#### Editing a mime types properties

Before you can edit a &MIME; types property, you must first specify which &MIME; type. Simply browse through the categories until you find the &MIME; type you want to edit, then click once on it with the mouse.

As soon as you have selected the &MIME; type, the current values of the &MIME; type will appear in the module window.

You will notice the current values are split into two tabs: General and Embedding

General

- There are 4 properties for each &MIME; type in this tab:

  1. Mime Type Icon is the icon that will be visible when using &konqueror; as a file manager.

  2. Filename Patterns is a search pattern which &kde; will use to determine the &MIME; type.

  3. Description is a short description of the file type. This is for your benefit only.

  4. Application Preference Order determines which applications will be associated with the specified &MIME; type.

Embedding Tab

- The Embedding tab allows you to determine if an file will be viewed within a &konqueror; window, or by starting the application.

#### Changing the Icon

To change the icon, simply click on the Icon button. A dialogue box will appear, which will show you all available icons. Simply click once with the mouse on the icon of your choice, and click OK.

#### Editing the mime-type patterns

The box labelled Filename Patterns, determines what files will be included within this mime-type.

Usually, files are selected based on their suffix. (Examples: Files that end with `.wav` are sound files, using the WAV format and files that end in `.c` are program files written in C).

You should enter your filename mask in this combo box.

The asterisk (`*`) is a wildcard character that will be used with nearly every mime type mask. A complete discussion of wildcards is beyond the scope of this manual, but it is important to understand that the asterisk (in this context), matches any number of characters. As an example: `*.pdf` will match `Datafile.pdf`, `Graphics.pdf` and `User.pdf`, but not `PDF`, `Datafile.PDF`, or `.pdf`.

It is very beneficial to have multiple masks. One for lower case, one for upper case, &etc; This will help ensure that &kde; can determine the file type more accurately.

#### Editing a mime types description.

You can type a short description of the &MIME; type in the text box labelled Description. This label is to help you, it does not affect the function of the &MIME; type.

#### Editing the application associations

There are four buttons (Move Up, Move Down, Add and Remove) and a combo box (which lists the applications) which are used to configure the applications.

The combo box lists all of the applications associated with a specific &MIME; type. The list is in a specific order. The top application is the first application tried. The next application down the list is the second, etc.

What do you mean there is more than one application per &MIME; type? Why is this necessary?

We started out by saying that &kde; comes preconfigured with hundreds of file associations. The reality is, each system that &kde; is installed on has a different selection of applications. By allowing multiple associations per &MIME; type, &kde; can continue to operate when a certain application is not installed on the system.

As an example:

For the &MIME; type `pdf`, there are two applications associated with this file type. The first program is called PS Viewer. If your system does not have PS Viewer installed, then &kde; automatically starts the second application Adobe Acrobat Reader. As you can see, this will help keep &kde; running strong as you add and subtract applications.

We have established that the order is important. You can change the order of the applications by clicking once with the mouse on the application you want to move, and then clicking either Move Up or Move Down. This will shift the currently selected application up or down the list of applications.

You can add new applications to the list by clicking the button labelled Add. A dialogue box will appear. Using the dialogue box, you can select the application you want to use for this mime type. Click OK when you are done, and the application will be added to the current list.

You can remove an application (thereby ensuring that the application will never run with this &MIME; type by clicking once on the name of the application, and clicking the Remove button.

It is a good idea to use the Move Up and Move Down buttons to adjust the unwanted application to a lower position in the list, rather than deleting the application from the list entirely. Once you have deleted an application, if your preferred application should become compromised, there will not be an application to view the data document.

#### Embedding

By clicking on the Embedding tab, you are presented with three radio buttons in the Left click action group. These determine how &konqueror; views the selected &MIME; type:

Show file in embedded viewer

- If this is selected, the file will be shown within the &konqueror; window.

Show file in separate viewer

- This will cause a separate window to be created when showing this mime-type.

Use group settings.

- This will cause the mime-type to use the settings for the mime-type group. (if you are editing an audio mime type, then the settings for the audio group are used).

Below this is a listbox labelled Services Preference Order.

When you are in &konqueror;, you can right mouse click, and a menu will with an entry labelled Preview with... will appear. This box lists the applications that will appear, in the order they will appear, under this menu.

You can use the Move Up and Move Down buttons to change the order.

#### Making changes permanent

When you are done making any changes to mime types, you can click Apply to make your changes permanent, but keep you in this module.