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The "Action" Window

Action Toolbar Part1

Window Type

As with every window header, the first button allows you to set the window type.

Full Window

Maximise the window, or return to the previous window display size; return to the previous screen setting (Ctrl↑ or ⇧ ShiftSpace).

Home

All visible blocks are displayed completely, centered in the window (↖ Home).

Action Toolbar Part2

Pin 

Causes this Action window to show the current data block regardless of what object is selected or active.

Action Menu 

Choose another Action from the list of available Actions. The option Add New makes a complete copy of the current Action. This is not visible; only the name in the adjacent button will change.

AC:

Give the current Action a new and unique name. After the new name is entered, it appears in the list, sorted alphabetically.

Users 

If this button is displayed, there is more than one user for the Action block. Use the button to make the Action "Single User".

Unlink Action 

The current Action is unlinked.

Action Toolbar Part3

Bake 

Generate an action based of the current action where the constraints effects are converted into IPO Keys.

Lock 

This button locks the update of the 3DWindow while editing in the ActionWindow, so you can see changes made to the Action in realtime in the 3DWindow.

ActionWindow

The ActionWindow gives an overview of the current Armature Keys or Relative Vertex Keys or Object keys for an Armature or Object. Each key (bone position) is a small diamond, yellow for selected keys, gray for un-selected. It presents the time, in frames, on a horizontal axis and, vertically, in as many stripes as there are bones in the armature, or Relative Vertex Keys. You may use standard selection gestures (e.g. B and mouse movement) to select multiple keys. In the example picture above, there are three keyframes for the armature (frames 1, 11, and 22), and each bone has a key for each keyframe.

If the object is an armature, each bone keys is represented as a grey diamond at the pertinent frame, or yellow if the key is selected. If it showing Mesh keys, the diamonds are present where a Key is assigned a given value. This can be assigned via IPO or via the sliders in the ActionWindow.

If the "Sets IPO to be included as Action" button is enabled in the IPO header (looks like a headless man ... beside the IPO type dropdown), then Object IPO types will have Action keys created for them.

The mouse

Key	Function
LMB	Sets current frame.
MMB and drag	The view is translated.
CtrlMMB and drag	Zoom in or out of the ActionWindow, this happens only horizontally.
RMB	Select a strip (if clicked on strip name) or a Key (if clicked on a Key). Use ⇧ Shift to enlarge or reduce the selection (extend select).
⇧ ShiftRMB	Add/remove from selection.
AltRMB	nSelect all keyframe markers on that side of the current frame marker.

The HotKeys

Key	Function
↖ Home	All visible blocks are displayed completely, centred in the window.
A	Select All / deselect All. If one block is selected, everything is first deselected.
B	Border select. Draw a rectangle with the LMB ; all blocks that fall within this rectangle are selected. Draw a rectangle with the RMB to deselect the blocks.
C	Centers view at current frame.
⇧ ShiftD	Duplicates the selected Keys. Duplicates are automatically in Grab mode.
G	Translation mode (the Grabber). This works on selected blocks and only horizontally, to change frames. The following options are available in translation mode: ↑, ↓, ←, → - The mouse cursor can be moved exactly 1 pixel with these keys. Ctrl - The Keys are displaced by 1 frame steps. ⇧ Shift+Ctrl - The Keys are displaced by 0.1 frame steps. Grabber terminates with: LMB , Space or ↵ Enter: Move to a new position. RMB or Esc: Everything returns to the old position.
T	Allows for definition of the type of interpolation for the selected strips: Constant is piecewise constant (abrupt changes). Linear is linear interpolation (abrupt changes in derivative). Bezier is default fluid interpolation.
X	Delete selected Keys.