You interact with mwm with a pointing device, usually a mouse, or by pressing various combinations of keys on the keyboard, or both. The Motif Window Manager (mwm) uses an object-action model of interaction. You select a window, menu, icon, or other graphic object and indicate an action for that object.

A graphic image on the display, called a pointer, tracks the movement of the mouse on your desk. When X starts up, the pointer has an × shape. (This shape is the default; the pointer shape can be customized.) When you move the mouse, the image of the pointer may change. The pointer shape is meant to provide a visual cue as to the activity that is being performed. For example, inside a terminal window or text editor, the pointer may look like an I-beam (see Figure 2-1).

You can access most window managing functions through decorations on the mwm window frame (see Figure 2-2).

Table 2-1 lists the window frame decorations and their associated functions.

Before a window can receive input or other window management functions, you must select a window for input focus. To avoid ambiguity, only one window can be selected at a time. This window is said to be the active window. When a window is active, the color or shade of the window frame changes. You can choose the color or shading for active and inactive windows (see Chapter 5).

The input focus policy determines how a window is selected. The window manager supports both an explicit focus policy and an implicit focus policy. The implicit focus policy is also known as the pointer focus policy. The default input focus policy is explicit, which means that you must click Button 1 on the window frame or press Alt Tab to change the input focus from one window to another.

Pointer input focus policy causes mwm to change the input focus to match the pointer's position; no other actions are required. Thus, the window that contains the pointer always has the input focus. You can specify this input focus policy by modifying the defaults in the X configuration file. (See Chapter 5 for further information about setting input focus policy.)

The easiest way to select a window for input is to move the mouse so that the pointer rests within the frame of the window you want to use. If an explicit focus policy is in effect, you also need to click Button 1. With explicit focus policy, only the window selected for keyboard focus receives keyboard input, regardless of where the pointer is located. If you are using the explicit focus policy, you can also move the input focus using the keyboard. Pressing Alt Tab moves the input focus to the next window in the window stack; pressing Shift Alt Tab moves the input focus to the previous window.

To raise a partially concealed window to the top of the window stack, or in other words to the front of the display, position the pointer on the window's frame and click Button 1. Be sure that the pointer is not resting on one of the window frame command buttons: minimize, maximize, or Window Menu (see Figure 2-2).

The window manager also provides default methods for raising a window from the keyboard, as shown in Table 2-2.

When you are using an explicit input focus policy, raising a window to the top of the stack also sets the input focus to that window. If you are using a pointer focus policy, however, the window manager does not automatically set input focus to the raised window. In other words, a window can continue to receive input even though it is not at the top of the stack. You can, however, set a resource in the the X configuration file to move a window automatically to the top of the stack when you set input focus to that window (see Chapter 5).

The Window Menu provides an alternate way to access window manager functionality. There are two ways to use the Window Menu:

Figure 2-3 illustrates a posted Window Menu.

Table 2-3 lists the default Window Menu selections and their corresponding functions.

Menu selections for functions that are not immediately applicable are grayed out; selecting these items has no effect.

You can also select Window Menu items from the keyboard. Accelerators are key bindings that provide quick access to menu functions without posting the menu. For example, Alt F3 lowers the window. Accelerators appear in the menu to the right of their associated menu items.

Mnemonics select a menu item after the Window Menu is posted. Mnemonic keys are indicated in a menu item by an underlined character in the menu item label. For example, pressing M while the Window Menu is posted has the same effect as selecting Move with the mouse.

To move a window, position the pointer in the window's title area, press and hold down Button 1 and drag the mouse. The pointer usually changes shape for the duration of the operation. As you move the mouse, by default a wire frame outline shows the current location of the window. You can set a resource so that the move operation displays the window itself rather than an outline (see Chapter 5). A feedback window is also displayed, which shows the current location of the window in pixels relative to the origin of the root window.

When the wire frame is where you want the window to be located, release the button. The window moves to that location. A move in progress can be canceled by pressing Cancel.

You can also move a window from the keyboard. First, select Move from the Window Menu or press the accelerator Alt F7. The arrow keys move the window in the direction of the arrow. Holding down Ctrl as you press the arrow keys moves the window in larger increments (see Table 2-4). You can also move the window by moving the mouse after the move operation has been initiated from the keyboard. Press Return to complete the move operation.

You can change the size of a window by positioning the pointer on one of the following window frame resize handles:

Each handle has a distinct cursor shape (see Figure 2-4).

The direction and outcome of the resize operation depends on which handle you grab. Press Button 1 while the pointer is on one of these handles to grab the window. Move the mouse to expand or contract the window. A wire frame outline shows the changing dimensions. Also, a small feedback window displays the current dimensions of the frame. Release Button 1 to complete the resize operation. You can cancel the operation at any time by pressing Cancel.

You can also resize a window from the keyboard. First, select Size on the Window Menu or press the accelerator Alt F8. To change the size of the window, press the arrow key that points in the direction of the dimension that you want to change. Then, you can increase or decrease the size of the window by pressing on the same or opposite arrow key. Press Return when the window is the size that you want.

Maximizing a window makes the window its largest allowable size. A window's largest possible size can be limited by the application program or by configured resources.

To maximize a window, position the pointer on the maximize button on the far right of the window frame and click Button 1. The client window expands to the maximum size set by either the application program or the configured resources. By default, the maximized window fills the screen.

Once the window is maximized, the large square image on the maximize button appears pressed into the screen. Clicking Button 1 on the recessed maximize button restores the window to its previous size and position.

You can also maximize a window by selecting Maximize on the Window Menu or pressing the accelerator Alt F10. You can restore a maximized window by selecting Restore on the Window Menu or by pressing the accelerator Alt F5.

Icons are small graphic representations of windows that are used to reduce clutter on the screen. You can turn a client window into an icon or change an icon back into a window at any time.

A typical icon has two parts, an image and a label, as shown in Figure 2-5.

By default, the window manager arranges icons along the bottom of the display, from left to right. Icons can also be placed into an icon box. The icon box is an mwm window that holds icons. The icon box can also be minimized (turned into an icon). You can specify the creation of an icon box by setting a value in the X configuration file (see Chapter 5).

An icon also has a menu, which contains the same selections as the Window Menu of the associated client window. To display the icon's menu with the mouse, position the pointer anywhere on the icon and press Button 3. To display the icon's menu from the keyboard, press Shift F10 or Alt Space. You browse through the menu either by dragging the mouse or pressing the arrow keys. To select an item, either release the mouse button when the item is highlighted or press Return. Menu selections that are not applicable are grayed out. Once the menu is posted, you can cancel it by pressing Cancel or by clicking Button 3 anywhere outside the menu.

Closing a window removes it from the screen. To close a window, select Close from the Window Menu or press the accelerator Alt F4 when the window is selected. If the window is the MainWindow of a running application, the application usually will terminate. Not all applications respond gracefully to this type of termination. Some applications may force you to perform additional steps to terminate if you close its MainWindow. If an application uses multiple independent primary windows, selecting Close may either close just that window or cause the application to exit.

The root menu provides access to mwm functionality that relates to the screen as a whole. For example, the root menu may contain selections to create a new window or restart mwm. You can specify items for the root menu in the mwm configuration file (see Chapter 6).

To display the root menu, position the pointer anywhere on the root window and press mouse Button 3. Figure 2-6 shows the default Root Menu.

Table 2-5 lists the default root menu selections and their associated functions.

Usually, you use Restart when you have changed mwm resources and you want the changes to take effect (see Chapter 4). When you select Restart, the window manager verifies that you really want to restart. Move the pointer to the control labeled OK and click Button 1 to restart; move the pointer to the control labeled Cancel and click Button 1 to cancel the procedure.

The window manager provides virtual desktop capabilities to the Motif user. Some window managers limit the canvas upon which the user positions windows to the area visible on the display screen. The Motif window manager does not have this restriction. Instead, the display screen may be thought of as a viewport onto an infinite-sized canvas. This allows you to pan the view over a root window that appears to be much larger than the actual size of the display screen. The mwm can be panned to any location that a window can be placed. This allows you to position windows on a root window of virtually unlimited size.

Access to mwm's virtual desktop capabilities is provided via the mwm and X resource files. There are basically three ways to move about and view objects on the virtual desktop:

The mwm provides these capabilities through resource files that you can set up and access via an mwm menu, or through key or button bindings. Refer to Chapter 6 for a description of menu functions and how they work.