/// <summary>
/// Saves the form state.
/// </summary>
/// <remarks>
/// All exceptions are ignored to make sure that this miscellaneous function
/// does never break the application.
/// </remarks>
/// <returns>True if form state was successfully stored, false if an error
/// occurred</returns>
public bool SaveState()
{
if (Form.WindowState == FormWindowState.Minimized)
{
// don't save state if minimized
return(false);
}
try
{
// get the current form state
T formState = GetCurrentState();
// write form state
FormStatePersistence.WriteToXml(_fileName, formState, typeof(T));
}
catch (Exception ex)
{
_msg.Warn("Error saving form state", ex);
// ignore errors
return(false);
}
return(true);
}
/// <summary>
/// Saves the window settings for the form.
/// </summary>
/// <remarks>
/// All exceptions are ignored to make sure that this miscellaneous function
/// does never break the application.
/// </remarks>
/// <returns>True if settings were successfully stored, false if an error
/// occurred</returns>
public bool SaveSettings()
{
if (_form.WindowState == FormWindowState.Minimized)
{
// don't save state if minimized
return(false);
}
else
{
try
{
// get the current settings for the form
WindowSettings settings = GetCurrentSettings();
// write settings
FormStatePersistence.WriteToXml(_fileName, settings, _settingsType);
}
catch (Exception ex)
{
_msg.Warn("Error saving window settings", ex);
// ignore errors
return(false);
}
return(true);
}
}
/// <summary>
/// Initializes a new instance of the <see cref="FormStateManager<T>"/> class.
/// </summary>
/// <param name="form">The form.</param>
/// <param name="callingContextID">The calling context ID.</param>
public FormStateManager([NotNull] Form form,
[CanBeNull] string callingContextID = null)
{
Assert.ArgumentNotNull(form, nameof(form));
Form = form;
_fileName = FormStatePersistence.GetFileName(form.GetType().Name, callingContextID);
}
/// <summary>
/// Restores the saved geometry settings (if existing) for the form and
/// returns a value that indicates if the settings have been successfully
/// restored.
/// </summary>
/// <param name="restoreOption">options for the restore.</param>
/// <remarks>
/// All exceptions are ignored to make sure that this miscellaneous function
/// does never break the application. However, it is guaranteed that all
/// changes are fully rolled back.
/// </remarks>
/// <returns>True if stored settings have been encountered and successfully
/// applied, false if no stored settings existed for the form or an error
/// occurred</returns>
public bool RestoreSettings(FormStateRestoreOption restoreOption)
{
// read settings from file
WindowSettings settings;
try
{
settings = (WindowSettings)FormStatePersistence.ReadFromXml(
_fileName, _settingsType);
}
catch (Exception e)
{
_msg.Warn("Error reading stored settings", e);
// ignore the exception
return(false);
}
if (settings == null)
{
return(false);
}
else
{
// get the current settings for rollback in case of exception
WindowSettings origSettings = GetCurrentSettings();
try
{
ApplySettings(settings, restoreOption);
}
catch (Exception e)
{
// roll back and ignore the exception
try
{
ApplySettings(origSettings);
}
catch
{
_msg.Warn("Unable to roll back window settings", e);
}
finally
{
_msg.Warn("Error applying stored window settings", e);
}
return(false);
}
}
return(true);
}
/// <summary>
/// Restores the saved form state (if existing) for the form and
/// returns a value that indicates if the form state has been successfully
/// restored.
/// </summary>
/// <param name="restoreOption">options for the restore.</param>
/// <remarks>
/// All exceptions are ignored to make sure that this miscellaneous function
/// does never break the application. However, it is guaranteed that all
/// changes are fully rolled back.
/// </remarks>
/// <returns>True if stored form state has been encountered and successfully
/// applied, false if no stored form state existed for the form or an error
/// occurred</returns>
public bool RestoreState(
FormStateRestoreOption restoreOption = FormStateRestoreOption.Normal)
{
// read state from file
T formState;
try
{
formState = (T)FormStatePersistence.ReadFromXml(_fileName, typeof(T));
}
catch (Exception e)
{
_msg.Warn(
"Error restoring saved window state. Window state is reset to defaults.", e);
// ignore the exception
return(false);
}
if (formState == null)
{
return(false);
}
// get the current form state for rollback in case of exception
T origFormState = GetCurrentState();
try
{
ApplyFormState(formState, restoreOption);
}
catch (Exception e)
{
// roll back and ignore the exception
try
{
ApplyFormState(origFormState);
}
catch
{
_msg.Warn("Unable to roll back form state", e);
}
finally
{
_msg.Warn("Error applying stored form state", e);
}
return(false);
}
return(true);
}
