Not all mouse-based selection techniques are available for all controls. There are techniques for selecting or deselecting individual elements or groups of elements. The group techniques range from basic group selection techniques (such as range selection) to more advanced techniques (such as margin selection). This section describes the different types of individual and group selection techniques. It also describes adjustment techniques, which allow users to change an identified selection by either adding or removing elements from it (thus enlarging or shrinking the region).
Mouse-based selection depends on the select and toggle modes. Select mode is more common for basic selection. The discussion in this section assumes that select mode is in use. For more information on selection modes, see the Selection Modes reference page.
When select mode is active, individual selection techniques allow the user to select an element. All other elements are deselected, whether they were originally selected or not. There are two individual selection techniques: point and browse.
With the point technique, the user clicks the SELECT button on the desired element (see Figure 26).
In select mode, if a user tries to use the point technique to select text, or in the background of a graphics scope, this technique simply deselects everything. Because the pointer is not on an element that can be selected, this results in a selection that does not contain anything.
Figure 26. Point Technique.
For more information, see the Point Technique reference page.
With the browse technique, the user presses the SELECT button within the scope, moves the pointer (browses) until it is on the desired element, then releases the button. As the pointer moves over the elements that can be selected, selection emphasis is moved from one element to the next until the final selection is made at the release of the SELECT button (see Figure 27).
Because the elements that can be selected are emphasized as the pointer moves over them, the browse technique is a way to identify these elements.
Figure 27. Browse Technique.
For more information, see the Browse Technique reference page.
When select mode is active, group selection techniques allow the user to select a group of elements at one time. Group selection techniques include:
The following sections describe these techniques.
There are two range techniques: range swipe and range click. Both techniques act on a group of ordered elements.
With the range swipe technique, the user presses the SELECT button at the beginning of the range of elements to be selected, then moves the pointer to the end of the range and releases the button. All the elements within this range are then shown with selected emphasis (see Figure 28).
Figure 28. Range Swipe Technique in Text.
With the range click technique, the user clicks the SELECT button at the beginning of the range of elements to be selected and Shift SELECT at the end of the range. The elements within this range are then shown with selected emphasis (see Figure 29). The range click technique is useful in text for defining the beginning and ending point of a selection. People with repetitive stress injuries who find it painful to move the mouse while pressing a button will find the range click technique helpful. It is also useful when selecting a large range of elements that does not fit on one screen. The user can click on the beginning point, then scroll to the end of the range and click on the ending point.
Figure 29. Range Click Technique in a Menu.
For more information, see the Range Click Technique and the Range Swipe Technique reference pages.
There are two area techniques: area swipe and area click. They have the same relationship to each other as the range click and range swipe techniques. Both area techniques act on a group of contiguous elements (see Figure 30).
With the area swipe technique, the user presses the SELECT button on the location where the boundary is to begin and moves the pointer, creating a framing rectangle (or marquee) between the two corners (some implementations might have a boundary shape other than a rectangle). The area swipe technique is useful in containers and graphics scopes.
With the area click technique, the user clicks the SELECT button at one corner of an area, then clicks Shift SELECT at the diagonally opposite corner of the area, encompassing the elements in a rectangle. The elements within this area are shown with selected emphasis.
Figure 30. Area Technique.
For more information, see the Area Click Technique and Area Swipe Technique reference pages.
The touch swipe technique allows a user to select noncontiguous elements one at a time by "touching" each desired element. To perform a touch swipe selection, the user presses the SELECT button on the screen background and moves the cursor. As the cursor moves across the screen, each "touched" element becomes selected and is shown with selected emphasis. The touch swipe technique is useful in containers and graphics scopes.
For more information, see the Touch Swipe Technique reference page.
There are two advanced selection techniques: margin and multilevel. These techniques enable the selection of groups of elements without directly interacting with the elements themselves.
The margin technique is available for selection scopes that have margins, such as text. When margin selection is in effect, the user performs a selection technique, such as the point technique, at the margin of the scope of selection (see Figure 31). This results in the selection of a related group of elements within that selection scope. For example, in text the left margin may contain a margin element for each line. A user could use the point technique and click the SELECT button at the left margin of a line to select that margin element, which in turn would select all the characters on that line. When combining the margin technique with the range swipe technique, pressing the SELECT button at the left margin and swiping down the lines in the range would select the lines from the margin and the swiped margin elements, which in turn would select all the characters on those lines.
Figure 31. Margin Technique.
The multilevel technique is available for selecting groups of elements that have some sort of hierarchical structure. The user can click either multiple times on text or adjacent to an element. With the first click, that text or element is selected. With each subsequent click, higher-level groups of adjacent elements are selected (see Figure 32). For example, a SELECT double-click (two clicks) would select a word, and subsequent clicks would select lines, paragraphs, sections, and so on. The user can combine this technique with the range techniques to select a hierarchical range of text or elements quickly. For example, in text SELECT double-press (two presses) and move would select a range of text one word at a time.
Figure 32. Multilevel Technique.
For more information, see the Margin Selection Techniques and Multilevel Selection Technique reference pages.
After an individual or group element has been identified for selection, a user can change the existing selection by either enlarging or shrinking the region of selected elements (see Figure 33). The adjustment technique involves using the ADJUST button, which the user can perform with Shift SELECT or TRANSFER. (Refer to Appendix B. "Keyboard Model and Key Bindings" for a description of mouse models.) There are two adjustment techniques, adjust click and adjust swipe. These have the same relationship as the range and area techniques described earlier.
Figure 33. Selection Adjustment.
The adjust click technique either enlarges or reduces a range or area, depending on the location of the point relative to the selection. The user adjusts the selection by clicking the ADJUST button at the point where the user wants the selected range or area to be extended or reduced. The affected elements are then shown with or without emphasis, as relevant. For example, if a user has already selected an area of elements, then wants to reduce the number of selected elements, the user can click the ADJUST button on the point within the existing selection area. The elements still contained within the area remain unemphasized. However, the elements falling outside the new area are deemphasized. The range or area click techniques are the equivalent of initially using the point technique to select an element, then moving the mouse to another point and using the adjust click technique.
The effect an adjustment has on a selection depends on the various selection policies (in particular, the adjust policy) in effect. Refer to the Selection Policies reference page for a description of the various selection policies.
With the touch swipe technique in select mode, clicking the ADJUST button on a particular element adds the element to the selection.
For more information, see the Area Adjust Click Technique reference page.
The adjust swipe technique is similar to adjust click, except that after pressing the ADJUST button, the user can move the mouse to continue adjusting the selected region before releasing the button.
The user can also use the adjust swipe technique with advanced selection techniques. For example, after selecting some text, the user can double-press the ADJUST button or move to extend the selection one word at a time.
For more information, see the Area Adjust Swipe Technique reference page.