Smart Mouse Selection

"Smart Mouse" selection is a shortcut, simplified way to make selections that is similar to selection methods used in editing operations with many Windows applications. Smart mouse selection ignores selection modes and selection object filters and works only if the mouse is not busy in a command mode. As such, it is particularly useful when editing controls on forms or for casual editing of drawings, when the mouse is not usually engaged in a command. Visual Studio users will recognize the similarity between smart mouse selection with Manifold forms and forms editing in Visual Studio.

Pressing the ESC key will escape from any tool mode, such as zoom tool or selection tool and will restore default smart mouse selection. Pressing ESC is therefore a handy way of quickly exiting from some tool mode and getting back into default smart mouse selection.

In Manifold, commands involving the mouse are normally controlled by whatever toolbar button is engaged. To use Select Box for example, we push the Select Box button in and then use the mouse in this command. If the mouse is engaged in a different command mode (such as Zoom In or Zoom Out) the mouse works within whatever command has been chosen. Sometimes we would like fast and simple selection when the mouse is not engaged in any other command. For example, when moving objects around in maps we often want to select only one object and then drag it to another position. In such cases it is faster to do selection in a "modeless" way. Smart mouse selection provides a fast, simple and modeless way of doing selection in such circumstances.

Smart mouse selection is used to select items for editing in drawings, forms, labels, and layouts. An object selected with a CTRL-ALT click will appear with edit handles that can be used to move or reshape the object. An object chosen for editing is also called the primary selected object.

This topic is written using drawings and drawing objects as examples. The same moves will work with items in layouts, labels or controls in forms as well. See the Editing Forms topic for examples of using smart mouse selection with forms.

Smart mouse selection is intended for fast, casual selections during editing operations. Smart mouse selection does not use selection modes. To make selections using selection modes, use the selection tools described in the Selection topic.

Smart Mouse Touch Selection

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The simplest form of smart mouse selection is to click on an object to select it. This is a smart mouse version of Select Touch. For example, clicking on an area object in a drawing will select it. CTRL-ALT-clicking on an object will select it for editing, as seen above.

To deselect an object from editing, CTRL-click on it. This toggles it to unselected mode.

See the Editing Objects topic for examples and more information on interactive editing with smart mouse selection.

Keyboard Modifiers with Smart Mouse Touch Selection

Because a selection may already exist in the drawing when we wish to select an object for editing, smart mouse selection uses keyboard modifiers to allow a richer set of commands.

Click	Equivalent to Select Touch in Replace mode. Clicking into an empty part of the drawing deselects all objects.
CTRL-ALT Click	Select an object for editing, making it the primary selected object. Does not change the selection state of other objects.
CTRL Click	Invert the selection state of the object without changing the selection state of any other object. Equivalent to Invert mode.
SHIFT Click	Select the object if it is not yet selected. Does not change the selection state of other objects. Equivalent to Add mode.

Smart Mouse Box Selection

When clicked on an empty region and dragged the mouse automatically makes a box selection analogous to using the Select Box selection tool in Select Replace mode. This is a general shortcut for selection. To select an object as the primary selected object for editing, CTRL-ALT click on it.

Keyboard Modifiers with Smart Mouse Box Selection

The following keyboard modifiers may be used with smart mouse box selection:

Click and drag	Click on an empty region and drag to make a box selection in Select Replace mode. Selects all objects that are entirely within the selection box.
CTRL	Click on an empty region and drag to make a box selection in Invert Selection mode.
SHIFT	Use an open box selection to select all objects any part of which are within the selection box.

Use within Layouts Components and Forms

Although we can always use the regular, dedicated selection commands covered in the Selection topic, for some components smart mouse selection is the most typical way of making selections. With Layouts and Forms , for example, smart mouse selection will be used by most users as their primary means of making selections.

Notes

Why is it called "smart mouse" selection? This is based on the idea that to support this type of selection the mouse cursor in its default mode must understand a lot about its environment. For example, it must be able to keep track of and know when it is clicked on a drawing object (and, for that matter, when the object is in the active layer if the mouse hovers in a map window) and much more. This requires considerably more thought for the cursor than merely being a default Windows cursor, so it is said to be a "smart mouse" cursor.

Note that the default action of the mouse in "smart mouse" moves depends on the context of where it is clicked and how it is moved. For example, clicking on an empty region and dragging creates a box selection mouse move. Clicking on an object and dragging is a drag-n-drop operation.

Inconsistency in Selection Methods

Advanced Manifold users will notice that there is a slight inconsistency in how selection operates in different settings, in particular how selection works in drawings when using smart mouse mode and how selection works in tables.

The general idea in Manifold is to have selection governed by both the selection mode desired (replace, add, subtract, invert, intersect) as well as by the operation of whatever selection tool has been put into play (Select touch, Select box, etc.). This general idea is modified in two cases, smart mouse selection in drawings and selection in tables, to allow simplified operation in smart mouse selection and to conform to user habits fostered by other Windows software in the case of tables.

Smart mouse mode uses neither selection tools nor selection modes. It provides a simplified, default way of selecting objects. In drawings, if a selection tool such as Select touch or Select box is used the selection mode is always honored. Default smart mouse mode, which is available when some other tool is not in play, does not use the current selection mode. The advantage of such a difference between regular selection tools and smart mouse mode is that smart mouse mode can be a simple, default way of selecting objects. The disadvantage of this difference is that it is a difference and thus something that must be remembered.

Selection in tables will honor selection modes, but the visual selection tools used with drawings are not used in tables, as we can see by jumping ahead to the Selection in Tables topic. Because operations with tables are common in many Windows applications, in the case of tables Manifold adheres to the common Windows practice of selecting records in a table by clicking on a dedicated "handle" column. Clicking on a record handle in a table window always uses the current selection mode.