CpBT -- Fabio Maulo
El 02/09/2010, a las 17:42, Kevin Anderson <[email protected]> escribió: > Thanks for the help with this. I am finding that implementing a "Session per > View Model" is problematic with a WPF application because there is quite > often a relationship between two view's (and thus view model's). > > For instance, we have a grid that display's a collection of records but > double clicking on a row brings up a detail view of the selected row. The > obvious solution was to pass the session from one view model to the other. > That was where things started to get really complicated. We have a button on > that view that uses information from that row and creates and an entirely new > entity (creates a job from a bid) and then we have another grid that could be > open displaying the collection of jobs. So do we use the session from the > bid's grid or the session from the job's grid? > > It seems to me that the "Session per view model" works fine as long as there > isn't any relationship's between views which in a WPF application is unlikely. > > If I try to use separate sessions for each view model I get the exception: > "Illegal attempt to associate a collection with two open sessions" which may > be caused by my not closing the grid's session when I open the detail, but I > can't close it because it's possible that some lazy loading may still be > invoked based on the grid's filtering by the use. > > I am thinking that this should be a FAQ type question and that it can't be > only me but it seems most questions related to session management are related > to HTTP request/response scenario's which is not helpful at all. > > On 10-09-02 12:47 AM, Jeff Doolittle wrote: >> @Oskar >> >> contradicted my own self at the very end! heh. >> >> On Aug 29, 9:17 pm, Oskar Berggren<[email protected]> wrote: >>> 2010/8/29 Jeff Doolittle<[email protected]>: >>> [...] >>> >>>> factory. Sessions are cheap to create. The rule is "One Session per >>>> Application" (assuming you have one database you're working with) and >>>> many, many, many Sessions. >>> Make that "one session _factory_ per application...", which I'm sure >>> Jeff intended to write. :) >>> >>> /Oskar >>> >>> >>> >>>> --Jeff >>>> On Aug 29, 4:22 pm, Kevin Anderson<[email protected]> wrote: >>>>> What are the implications of having one session (managed by IOC) that >>>>> is shared by the whole application? >>>>> We have a WPF, MVVM application that originally used one session for >>>>> each call to the repository, but found that we couldn't lazy load >>>>> anything because the session was gone. We moved the session of the view >>>>> model but found that in some instances a given object was being held in >>>>> two different sessions. We then tried moving the session all the way up >>>>> to the IOC and found that performance was fantastic. >>>>> I am concerned that there will be negative impacts from having one >>>>> session open for the lifetime of the application. >>>>> Any thoughts? >>>>> Thanks. >>>>> Kevin >>>> -- >>>> You received this message because you are subscribed to the Google Groups >>>> "nhusers" group. >>>> To post to this group, send email to [email protected]. >>>> To unsubscribe from this group, send email to >>>> [email protected]. >>>> For more options, visit this group >>>> athttp://groups.google.com/group/nhusers?hl=en. > > -- > You received this message because you are subscribed to the Google Groups > "nhusers" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/nhusers?hl=en. > -- You received this message because you are subscribed to the Google Groups "nhusers" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/nhusers?hl=en.
