Selection tool
Selecting objects
Use the Selection tool to select objects on the canvas. When an object is selected, you can do any number of things to it.
To select several objects at once, click in an empty area of the canvas and drag a box around the objects. Command- or Shift-click an object to add it to the selection or remove it from the selection.
To select a member of a group (or table), click once to select the group, then click again to select the member. The rest of the canvas dims to show that you are in group editing mode. Click anywhere outside the group to leave the group editing mode.
When an object is selected, the Style inspectors and Properties inspectors become enabled. You can use the inspectors to change anything about the selected object.
Moving objects
To move an object, click it with the Selection tool and drag it to a new location. If you want to move a line, you might have to detach its end points from any objects they're attached to. To move an object straight horizontally or vertically, hold Shift as you drag. To rotate an object, hold Command and drag one of its selection handles.
To move the selected object very precisely, press the arrow keys. Hold Option or Shift to move by larger steps.
If you have smart guides enabled, they appear as you drag to help you line up objects and space them evenly. Hold Command after you start dragging to temporarily enable or disable smart guides.
To drag a copy of an object instead of the object itself, hold Option as you drag.
Resizing objects
When you select something resizable, like a shape object or a group, it gains eight selection handles. Drag one of these handles to change the shape's size. Hold Shift while resizing the object to maintain the aspect ratio— that is, to avoid squishing it. Hold Option while resizing an object to keep it centered on the same point.
If you have smart guides enabled, they appear as you drag to help you size objects equally. Hold Command after you start dragging to temporarily enable or disable smart guides.
Creating new objects
To create a child of the selected object, Command-click an empty spot on the canvas. To create a sibling, Command-Option-click an empty spot on the canvas. The new shape uses the same style as the original shape. The line connecting the shapes uses the style of a line already connected to the original shape; if no lines already existed, it uses the Line tool's current style.
Editing points
When you select a connection line or a custom shape, it shows the points that define its shape; these points appear as tiny diamonds.
The most basic line (created with the Line tool) has two points: a red one at its source and a green one at its destination. A line may also pass through any number of blue midpoints. Drag one of the points to move it; by dragging the source or destination point you can make the line connect to or disconnect from other objects.
Custom shapes (created with the Pen tool) have blue control points at each vertex. Click a control point to select it; if a control point is hiding behind a selection handle, Option-Command-click to select it, or just select a different control point first to make the handles go away. If a control point has bezier handles, they appear when you select the point. Drag either of the two handles to adjust both of them, or Option-drag to adjust them one at a time. Shift-drag to constrain the handle's angle to 45-degree increments. Command-drag a point to give it handles. If you drag a handle close enough to the point itself, the handle disappears entirely.
The default way to add points to a line is to Option-double-click the line, but this can be changed in the General preferences.
To add a point to a custom shape, double-click somewhere along the shape's stroke.
To delete a point from a line or a custom shape, select it and then either press the Delete key or select Delete from the Edit menu.