TPJUserWdwState

Unit: PJWdwState.

This non-visual component enables the size, position and state of the form on which it is placed to be saved to and read to any persistent storage. The user is responsible for loading and saving the data. This is done by handling the OnReadData and OnSaveData events. The component is provided in case the user wishes to save control the storage used or the format in which data is written. To use the the registry or an ini file TPJRegWdwState or TPJWdwState respectively can be used.

The Save method saves the window information while Restore reads information in and sets the owning form window's size, position and state.

The component's AutoSaveRestore property governs whether window sizes, positions and states are automatically restored on opening and saved on closing or whether the user must explicitly call the Save and Restore methods.

The Options property can be used to customise how the stored data is interpreted and whether the window's saved state or size should be used or ignored.

It is only possible to have one instance of a TPJUserWdwState component on any one form. Neither can a TPJUserWdwState component be dropped onto a form that already contains either a TPJWdwState or a TPJRegWdwState component.

TPJUserWdwState exposes the following methods, properties and events, some of which are inherited unchanged from TPJCustomWdwState.

Methods

Method	Description
Create	Class constructor that permits only one instance of the component to be placed on a form.
CreateStandAlone	Class constructor for use when creating components at run time.
ReadWdwState	Overridden method that triggers the OnReadData event.
Restore	Restores the size, position and state of a window from the user provided storage.
Save	Saves the size, position and state of the window to user specified storage.
SaveWdwState	Overridden method that triggers the OnSaveData event.

Properties

Property	Description
AutoSaveRestore	Determines whether the window's size, position and state is automatically restored on creation and stored on destruction.
IgnoreState	Determines whether the window's saved state (maximised, normal or minimised) is applied on restoration. This property is deprecated - use the Options property instead.
MinimizeDelay	Sets the delay between displaying a normalised form on screen and minimising it if required.
Options	Determines how the component interprets the window display data read from storage.

Events

Event	Description
OnAfterWindowRestored	Event triggered after window has been restored and its state set.
OnAfterWindowSized	Event triggered after the window is sized but before it is physically restored.
OnReadData	Event triggered when the component needs the user to read data from persistent storage.
OnSaveData	Event triggered when the component needs the user to save data to persistent storage.

Note that the protected OnReadWdwState event of TPJCustomWdwState is not exposed by TPJUserWdwState.

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