KWin Rules

    From KDE UserBase Wiki

    Overview

    KWin allows the end-user to define rules to alter the behavior of an application's windows.

    For example, when an application is started, it can be forced to always run on Virtual Desktop #2. Or a defect in an application can be worked-around by using a rule to, say, always force the window on top of all others.

    This page will define the different settings and the attributes. For the impatient folks, working examples will be listed. Whenever possible, screen shots will be used to show example settings.

    Tip

    Panels can also be affected.


    KWin Rule Editor

    Invoking the Editor

    There are several ways one can invoke the Rules editor. Below are a couple:

    • Right-click on the title-bar of any window, choose Configure Window Behavior ... and in the Configure window, select Window Rules or
    • Configure Desktop -> Window Behavior -> Window Rules

    Anatomy

    The editor is composed of four tabs:

    1. Window matching
    2. Size & Position
    3. Arrangement & Access
    4. Appearance & Fixes

    As the name implies, Window matching is used to specify criteria to match one or more windows. The other three tabs are used to alter the characteristics of the matching windows.

    Rules

    Evaluation

    KWin evaluates the rules when an application starts and after editing rules. Any matching rule's attribute(s) override the application's corresponding attribute(s).

    Precedence

    In the Window Rules window, the rules are listed in the order in which they are processed.

    The rule at the top of the list is processed first, followed by the next rule until the end of the list is reached.

    Conflicts

    In the event two rules match a window and affect the same attribute, the first rule in the list takes precedence.

    Window Matching

    The Window Matching tab provides a series of matching-criteria fields used to identify application windows:

    • Window class (application) - match this window and all its children windows.
      • and Match whole window class
    • Window role - restrict the match to the function of the window (e.g. a main window, a chat window, etc.)
    • Window types - restrict the match to the type of window: Normal Window, Dialog Window, etc.
    • Window title - restrict the match to the title of the window.
    • Machine (hostname) - restrict the match to the host name associated with the window.

    Tip

    While it's possible to manually enter the above information, the preferred method is to use the Detect Window Properties button.


    For each field, the following operators can be applied against the field value:

    • Unimportant
    • Exact Match
    • Substring Match
    • Regular Expression - Qt's regular expressions are implemented. For additional information, web search qt regex nokia.
    Detect Window Properties

    The Detect Window Properties function simplifies the process of entering the matching-criteria.

    1. For the application you'd like to create a rule, start the application.
    2. Next, in the Window matching tab, set the number of seconds of delay before the Detect Window Properties function starts. The default is zero seconds.
    3. Click on Detect Window Properties and
    4. When the mouse-cursor turns to cross-hairs, place it inside the application window and left-click.
    5. A new window is presented with information about the selected window:
      • Class
      • Role
      • Type
      • Title
      • Machine (hostname)


    Click the OK button to back-fill the Window Matching criteria.

    By using a combination of the information, you can tailor whether a rule applies to an entire application (by Class) or a to a specific window Type within the Class - say a Toolbar.

    Window Attributes

    The attributes which can be set are grouped in three tabs:

    1. Size & Position
    2. Arrangement & Access
    3. Appearance & Fixes

    Each attribute has additional settings which determine when they're applied and depending on the attribute, there may be an additional argument.

    Attributes

    Tip

    Using Detect Window Properties back-fills values for attributes. For example the height and width arguments of the Size attribute is set to the height and width of the detected window.

    Tip

    Yes/No arguments are used to toggle attributes. For example, if a window's default behavior is to start horizontally maximized and you wish to disable this behavior, specify No as the argument to Maximized horizontally, on the other hand if you wish to force a window to start horizontally maximized, specify Yes.


    Size & Position
    Position
    Position the window's upper left corner at the specified x,y coordinate.

    Tip

    KWin's origin, (0,0), is the upper left.
    Size
    The width and height of the window.
    Maximized horizontally, Maximized vertically, Fullscreen
    These attributes are used to toggle the maximum horizontal/minimum horizontal/full-screen window attribute.
    Desktop
    Place the window on the specified (Virtual) Desktop. Use All Desktops to place the window on all Virtual Desktops.
    Minimized, Shaded
    Toggle the Minimize and Shading window attribute. For example, a window can be started Minimized or if it is started Minimized, it can be forced to not.

    Tip

    Maximized attribute is emulated by using both Maximized horizontally and Maximized vertically or Initial placement with the Maximizing argument.
    Initial placement
    Override the global window placement strategy with one of the following:
    • Default - use the global window placement strategy.
    • No Placement - top-left corner.
    • Smart - place where no other window exists.
    • Maximizing - start the window maximized.
    • Cascade
    • Centered
    • Random
    • Top-Left Corner
    • Under Mouse
    • On Main Window - restrict placement of a child window to the boundaries of the parent window.
    Ignore requested geometry
    Toggle whether to accept or ignore the window's requested geometry and ignore the global placement strategy.
    Minimum size, Maximum size
    The minimum and maximum size allowed for the window.
    Obey geometry restrictions
    Toggle whether to adhere to the window's requested aspect ratio.
    Arrangement & Access
    Keep above, Keep below
    Toggle whether to keep the window above/below all others.
    Autogroup with identical
    Toggle the grouping (commonly known as tabbing) of windows.
    Autogroup in foreground
    Toggle whether to make the window active when it is added to the group.
    Autogroup by ID
    Create a group via a user-defined ID. More than one rule can share the same ID to allow for seemingly unrelated windows to be grouped.
    Tiling
    Override the default window behavior to either Tiled or Floating.
    Skip taskbar
    Toggle whether to display the window in the taskbar.
    Skip pager
    Toggle whether to display the window in the virtual desktop list.
    Skip switcher
    Toggle whether to display the window in the ALT+TAB list.
    Shortcut
    Assign a shortcut to the window. When Edit... is clicked, additional instructions are presented.
    Appearance & Fixes
    No titlebar and frame
    Toggle whether to display the titlebar and frame.
    Active/Inactive opacity
    When the window is active/inactive, set its opacity to the percentage specified.

    Tip

    Active/Inactive opacity can only be affected when Desktop Effects are enabled.
    Focus stealing prevention
    Def
    Accept focus
    Def
    Ignore global shortcuts
    Def
    Closeable
    Def
    Window type
    Def
    Block compositing
    Def

    Disposition

    Do Not Affect
    Definition
    Apply Initially
    Definition
    Remember
    Def
    Force
    Def
    Apply Now
    Def
    Force Temporarily
    Def

    Examples

    Force a Window on a Desktop

    Force a Window on all Desktops

    Suppress a Window showing on Pager

    Force a Window to the Top

    Good for knotes

    Multiple Rules per Application

    e.g. Thunderbird on one desktop and composition window on any