Directory Opus Manual

If used by itself, this modifier affects the entire function. It can also be used to elevate a specific command rather than the entire button.

@ctx:=return "Go DRIVEBUTTONS";

This uses the evaluator to return a simple string; functionally this is no different to simply putting the Go DRIVEBUTTONS command on a toolbar button.

As a more complex example, the default Favorites Bar toolbar uses @ctx to build the displayed favorites list, by using the Evaluator to build a command line using the current localised name of the favorites bar branch:

@ctx:=return "Favorites SHOWICONS USEQUALKEYS BRANCH=""" + LanguageStr("FavoritesBar") + """;

This uses the evaluator LanguageStr() function to retrieve the translated name of a known string, and constructs a command line using the Favorites command to display that branch of the favorites tree.

For lister toolbars, you can use the minfiles, maxfiles and numfiles keywords to specify a minimum, maximum, or exact number of files which must be selected for the button to be enabled. Similarly, mindirs, maxdirs and numdirs can limit the number of selected folders.

Using the type keyword you can configure a button to be disabled unless at least one file is selected whose name matches the supplied wildcard pattern. (It is not required that all selected files match the pattern; only one.) You can also combine this with dirs for a button that works if a folder is selected or if a file of a certain type is selected. If you use type, it must be the last thing on the line, since everything after the = will be considered part of the pattern (allowing the pattern to include things which would otherwise be confused with other keywords and parameters).

You can also use a ! character to negate the test. It must be the first thing after the :. For example,

Paths may use aliases, environment variables, {apppath} codes, and so on, only when using wildcards (not regular expressions):

Go NEW
[
@functype:script
@script:vbscript
' script function here
]

For lister toolbars, you can use the minfiles, maxfiles and numfiles keywords to specify a minimum, maximum, or exact number of files which must be selected for the button to be visible. Similarly, mindirs, maxdirs and numdirs can limit the number of selected folders.

Using the type keyword you can configure a button to be hidden unless at least one file is selected whose name matches the supplied wildcard pattern. (It is not required that all selected files to match the pattern; only one.) You can also combine this with dirs for a button that is visible if a folder is selected or if a file of a certain type is selected. If you use type, it must be the last thing on the line, since everything after the = will be considered part of the pattern (allowing the pattern to include things which would otherwise be confused with other keywords and parameters).

You can also use a ! character to negate the test. It must be the first thing after the :. For example,

@if is a general test which works with any command, and @ifset is a specific test which only works with the Set command conditions. For example, @ifset:DUAL=on is equivalent to @if:Set DUAL=on.
The test @if actually performs is to evaluate whether a toolbar button with the specified command would appear highlighted or not. For example, if the Lister is in dual-display mode, a button with Set DUAL=toggle as the command would appear highlighted. Therefore, the @if:Set DUAL=toggle modifier would evaluate to true.

You can also evaluate whether a toolbar button would be enabled or not, using @if:enabled. For example, Navigation Lock is only enabled when a Lister is in dual-display mode. Therefore, the modifier @if:enabled Set NAVLOCK=Toggle would evaluate to true when the Lister was in dual-display mode.

You can also test if a variable has been set by the @set directive. Additionally, a button on the File Display toolbar can test if it's tied to the left or right file display.

For example, you could configure a button to read a folder into the right file display in a dual-display Lister, or into the current file display otherwise.

@if:Set DUAL=on           	// if DUAL mode is on
Set FOCUS=right             // give focus to the right file display
Go /mypictures OPENINRIGHT  // read directory into that file display
@if:else                    // otherwise
Go /mypictures              // read directory into current file display
@if:common                  // common commands (always executed)
Set VIEW=thumbnails         // set view to thumbnails mode

As another example, @ifset can use the RECYCLEBINEMPTY argument to test if the recycle bin is empty or not:

@ifset:RECYCLEBINEMPTY
@confirm The recycle bin is empty!
@ifset:else
Delete EMPTYRECYCLE

Conditional testing can also be used on buttons in the standalone viewer. The following function will toggle the display between 100% zoom and Grow To Page modes, by using @if to test the current zoom mode:

@if:Show VIEWERCMD=zoom,reset
Show VIEWERCMD=zoom,grow
@if:else
Show VIEWERCMD=zoom,reset

The possible forms of this modifier are:

You can negate the condition by prefixing it with a ! character. For example, all four of these are equivalent:

@if:!Set DUAL=on
@if:Set DUAL=off
@ifset:!DUAL=on
@ifset:DUAL=off

For example,

@ifsel:numfiles=2
<run program that accepts exactly two files>
@ifsel:else
<show an error message>

If something modifies variables, or other factors that affect dynamic labels, it should notify Opus so labels and toolbar layouts can be updated. Commands should use @toggle:update (see below) and scripts can use Command.UpdateToggle to do this.

For example,

Rename PATTERN * TO *
@script:vbscript
Function ....

Supported qualifier keys are shift, ctrl, alt and win.

As well as letters and numbers, the following named keys are also supported: backspace, capslock, delete , down, end, enter, escape, home, insert, left, numlock, pagedown, pageup, pause, printscr, right, scrlock, space, tab, up.

Paths may use aliases, environment variables, {apppath} codes, and so on, only when using wildcards (not regular expressions):

Depending on where the button is displayed, the highlight may appear as a checkmark (e.g. in a text-only menu), or as the icon or label background being drawn in a different color or style (similar to when the button is pushed).

Taking the Set VIEW=details command as an example, ordinarily the button would appear highlighted when the file display was in details mode, and not highlighted when it was in any other mode. The @toggle modifier can change this:

The @toggle modifier can also control when a button appears highlighted by testing a command, similar to the way @if and @ifset test commands to decide what to run. You can use this to highlight a button based on a command which is different to, or in addition to, the commands which the button actually runs.

For example, this button with no @toggle line will switch you to Details mode when clicked, and will appear highlighted when you are in Details mode as well:

Set VIEW=Details

When @toggle is not given, the highlighting (if any) is based on the first command in the button.

Using @toggle you can do things like run one Set command while testing for another. As a simple, somewhat contrived example, the button below switches to Details mode when clicked but appears highlighted when in Power mode:

Set VIEW=Details
@toggle:if Set VIEW=Power

You can make the @toggle test in addition to the first command, rather than instead of it, by putting an "&" character after the "if":

Set VIEW=Details
Set COLUMNSADD=thumbnail(0,96)
@toggle:if&Set COLUMNSTOGGLE=thumbnail

Without the @toggle line, the button above would be highlighted when the view mode was Details (due to the command) and the highlight would not be affected by the Thumbnail column (highlighting does not consider the second command). With the @toggle line added, the button will only be highlighted if the view mode is set to Details and the Thumbnail column is present.
You can omit the "Set" command name from the @toggle line; it will assume you mean the Set command if no name is specified. However, this allowance is to avoid breaking old buttons and we recommend you always specify the command when making new ones.

You can test for multiple commands at once by separating them with semi-colons. For example, you could leave out the ampersand and still test for both Details mode and the Thumbnail column using the following directive (and this will work regardless of any other commands in the button, or even as the only line in the button):

@toggle:if Set VIEW=Details;Set COLUMNSTOGGLE=thumbnail

You can also negate the result of a test with the exclamation mark in front of the Set clause. For example, to make the button appear checked in any mode other than Details:

@toggle:if !Set VIEW=Details

The @toggle directive can also test for the existence of a variable (one set via the @set directive). For this to work, the directive must be the very first line of the button, and the variable you are testing must have tab, Lister or global scope. You can use this to create your own custom toggle buttons that keep track of their state using scoped variables. For example:

@toggle:if $glob:TestVar
@if:$glob:TestVar
@set glob:TestVar
@if:else
@set glob:TestVar=on

This button tests for the existence of a global variable called TestVar. If the variable exists, the button will appear highlighted. Clicking the button evaluates the @ifset: directives and will reverse the state of the variable: if the variable is set, it will be deleted; otherwise, it will be set. The end result is a button that performs no function except to toggle a variable and its visible state each time it is clicked. (This can be useful if the variable controls other things, such as the behaviors of other commands or scripts, or the visibility of status bar elements.)

A button that begins with @toggle:if in this way will automatically update its appearance (to reflect a change in the state of the variable) whenever @set is used within it. If you use @set in a separate button or hotkey to change the variable, you need to force an update of the toggle button's appearance using the special command @toggle:update.

For example, if you have one button which highlights based on a variable but does not change that variable:

@toggle:if $glob:TestVar

And if you have another button which changes that variable but does not highlight based on it, then you will need to add the @toggle:update line to ensure the first button's highlight is updated when you click the second button:

@if:$glob:TestVar
@set glob:TestVar
@if:else
@set glob:TestVar=on
@if:common
@toggle:update

The @toggle:update command will also force all status bars to refresh, in case they are using variables to display or hide information.

You can also use @toggle:update to ensure buttons with dynamic labels (via @label, above) are updated after changing variables or other details the label depends on. This also ensures toolbar layouts are adjusted if the label widths change.