blt::container(3tcl)

NAME
container - Widget to contain a foreign window.

SYNOPSIS
container pathName ?options?

DESCRIPTION
The container widget lets you swallow another X11/Win32 toplevel or embed an X11 window from a foreign application into your Tk application. The foreign window is reparented inside of the widget. You can then place and arrange the container just as you would any Tk widget.

INTRODUCTION
Notebooks are a popular graphical paradigm. They allow you to organize many windows in a single widget. For example, you might have an application the displays several X-Y graphs at the same time. Typically, you can't pack the graphs into the same frame because they are too large. The other alternative is to pack the graphs into several toplevel widgets, allowing them to overlap on the screen. The problem is that all the different toplevel windows clutter the screen and are difficult to manage.

The container widget lets organize your application by displaying each graph as a page in a folder of a notebook. Only one page is visible at a time. When you click on a tab, the folder (graph) corresponding to the tab is displayed in the container widget. The container also lets you temporarily tear pages out of the notebook into a separate toplevel widget, and put them back in the container later. For example, you could compare two graphs side-by-side by tearing them out, and then replace them when you are finished.

A container may contain an unlimited number of folders. If there are too many tabs to view, you can arrange them as multiple tiers or scroll the tabs. The container uses the conventional Tk scrollbar syntax, so you can attach a scrollbar too.

EXAMPLE
You create a container widget with the container command.

    # Create a new container
    container .c

A new Tcl command .c is also created. This command can be used to query and modify the container. For example, to change the default borderwidth, you use the new command and the container's configure operation.

    # Change the default font.
    .c configure -borderwidth 2

You can then add folders using the insert operation.

    # Create a new folder "f1"
    .c coinsert 0 "f1"

This inserts the new tab named "f1" into the container. The index 0 indicates location to insert the new tab. You can also use the index end to append a tab to the end of the container. By default, the text of the tab is the name of the tab. You can change this by configuring the -text option.

    # Change the label of "f1"
    .ts tab configure "f1" -label "Tab #1"

The insert operation lets you add one or more folders at a time.

    .ts insert end "f2" -label "Tab #2" "f3" "f4"

The tab on each folder contains a label. A label may display both an image and a text string. You can reconfigure the tab's attributes (foreground/background colors, font, rotation, etc) using the tab configure operation.

    # Add an image to the label of "f1"
    set image [image create photo -file stopsign.gif]
    .ts tab configure "f1" -image $image
    .ts tab configure "f2" -rotate 90

Each folder may contain an embedded widget to represent its contents. The widget to be embedded must be a child of the container widget. Using the -window option, you specify the name of widget to be embedded. But don't pack the widget, the container takes care of placing and arranging the widget for you.

    graph .ts.graph
    .ts tab configure "f1" -window ".ts.graph" \
        -fill both -padx 0.25i -pady 0.25i

The size of the folder is determined the sizes of the Tk widgets embedded inside each folder. The folder will be as wide as the widest widget in any folder. The tallest determines the height. You can use the tab's -pagewidth and -pageheight options override this.

Other options control how the widget appears in the folder. The -fill option says that you wish to have the widget stretch to fill the available space in the folder.

    .ts tab configure "f1" -fill both -padx 0.25i -pady 0.25i

Now when you click the left mouse button on "f1", the graph will be displayed in the folder. It will be automatically hidden when another folder is selected. If you click on the right mouse button, the embedded widget will be moved into a toplevel widget of its own. Clicking again on the right mouse button puts it back into the folder.

If you want to share a page between two different folders, the -command option lets you specify a Tcl command to be invoked whenever the folder is selected. You can reset the -window option for the tab whenever it's clicked.

    .ts tab configure "f2" -command {
        .ts tab configure "f2" -window ".ts.graph"
    }
    .ts tab configure "f1" -command {
        .ts tab configure "f1" -window ".ts.graph"
    }

If you have many folders, you may wish to stack tabs in multiple tiers. The container's -tiers option requests a maximum number of tiers. The default is one tier.

    .ts configure -tiers 2

If the tabs can fit in less tiers, the widget will use that many. Whenever there are more tabs than can be displayed in the maximum number of tiers, the container will automatically let you scroll the tabs. You can even attach a scrollbar to the container.

    .ts configure -scrollcommand { .sbar set }  -scrollincrement 20
    .sbar configure -orient horizontal -command { .ts view }

By default tabs are along the top of the container from left to right. But tabs can be placed on any side of the container using the -side option.

    # Arrange tabs along the right side of the container.
    .ts configure -side right -rotate 270

SYNTAX
The container command creates a new window using the pathName argument and makes it into a container widget.

    container pathName ?option value?...

Additional options may be specified on the command line or in the option database to configure aspects of the container such as its colors, font, text, and relief. The container command returns its pathName argument. At the time this command is invoked, there must not exist a window named pathName, but pathName's parent must exist.

When first created, a new container contains no tabs. Tabs are added or deleted using widget operations described below. It is not necessary for all the tabs to be displayed in the container window at once; commands described below may be used to change the view in the window. Containers allow scrolling of tabs using the -scrollcommand option. They also support scanning (see the scan operation). Tabs may be arranged along any side of the container window using the -side option.

The size of the container window is determined the number of tiers of tabs and the sizes of the Tk widgets embedded inside each folder. The widest widget determines the width of the folder. The tallest determines the height. If no folders contain an embedded widget, the size is determined solely by the size of the tabs.

You can override either dimension with the container's -width and -height options.

CONTAINER OPERATIONS
All container operations are invoked by specifying the widget's pathname, the operation, and any arguments that pertain to that operation. The general form is:

    	pathName operation ?arg arg ...?

Operation and the args determine the exact behavior of the command. The following operations are available for container widgets:

pathName cget option
    Returns the current value of the configuration option given by option. Option may have any of the values accepted by the configure operation described below.

pathName configure ?option? ?value option value ...?
    Query or modify the configuration options of the widget. If no option is specified, returns a list describing all the available options for pathName (see Tk_ConfigureInfo for information on the format of this list). If option is specified with no value, then the command returns a list describing the one named option (this list will be identical to the corresponding sublist of the value returned if no option is specified). If one or more option-value pairs are specified, then the command modifies the given widget option(s) to have the given value(s); in this case the command returns an empty string. Option and value are described below:

    -background color
        Sets the border color of the container.

    -borderwidth pixels
        Sets the width of the 3-D border around the outside edge of the widget. The -relief option determines how the border is to be drawn. The default is 2.

    -command pattern
        Specifies to search for a window whose WM_COMMAND property matches the given pattern (X11 only). If no windows, or more than one window, matches the pattern, an error is generated. If pattern is the empty string, then no command search is performed. The default is "".

    -cursor cursor
        Specifies the widget's cursor. The default cursor is "".

    -height pixels
        Specifies the requested height of widget. If pixels is 0, then the height is height the embedded window plus the specified borderwidth. The default is 0.

    -highlightbackground  color
        Sets the color to display in the traversal highlight region when the container does not have the input focus.

    -highlightcolor color
        Sets the color to use for the traversal highlight rectangle that is drawn around the widget when it has the input focus. The default is black.

    -highlightthickness pixels
        Sets the width of the highlight rectangle to draw around the outside of the widget when it has the input focus. Pixels is a non-negative value and may have any of the forms acceptable to Tk_GetPixels. If the value is zero, no focus highlight is drawn around the widget. The default is 2.

    -name pattern
        Specifies to search for a window whose WM_NAME property matches the given pattern (X11 only). If no windows, or more than one window, matches the pattern, an error is generated. If pattern is the empty string, then no name search is performed. The default is "".

    -relief relief
        Specifies the 3-D effect for the container widget. Relief specifies how the container should appear relative to widget that it is packed into; for example, raised means the container should appear to protrude. The default is sunken.

    -takefocus focus
        Provides information used when moving the focus from window to window via keyboard traversal (e.g., Tab and Shift-Tab). If focus is 0, this means that this window should be skipped entirely during keyboard traversal. 1 means that the this window should always receive the input focus. An empty value means that the traversal scripts decide whether to focus on the window. The default is 1.

    -width pixels
        Specifies the requested width of the widget. If pixels is 0, then the width is the width the embedded window and the specified borderwidth. The default is 0.

    -window id
        Specifies the foreign embedded using its path or X window id.

pathName find -command|-name pattern
    Searches for all windows that match the given pattern. If the -command switch is given, all windows whose WWM_COMMAND property match pattern are returned in a list (X11 only). If the -name switch is given, all windows whose WWM_NAME property match pattern are returned in a list. The list returned will contains pairs of the window id and the matching property.

KEYWORDS
container, widget