View State and Persistence

PanAndZoom offers three levels of state management.

Immediate State

Current state is available through properties such as:

ZoomX, ZoomY
OffsetX, OffsetY
Rotation
Stretch

These are the values you bind into status bars or diagnostics panels.

View History

When EnableViewHistory is enabled, navigation APIs record viewport changes:

NavigateBack(...)
NavigateForward(...)
ClearViewHistory()
CanNavigateBack
CanNavigateForward

This is intended for undo-like viewport navigation rather than full application undo stacks.

Named Views And Serialized State

Two features support longer-lived persistence:

named views: SaveView(...), RestoreView(...), GetSavedViews()
serialized state: ExportState() and ImportState(...)

Avalonia.Controls.PanAndZoom.ZoomBorderState is the broadest persistence payload and is the right choice when you need to store or transmit a complete viewport configuration.

When To Use Each

Use current properties for UI display and lightweight telemetry.
Use view history for back/forward navigation inside a session.
Use saved views for user-defined bookmarks.
Use serialized state for persistence between runs or for collaboration workflows.