Hello again Patric and others. I have another question related to the previous one.
I now have the following things: * Foo model class * FooFormatter class which converts Foo objects into string representations * User interface with NSTableView which uses the FooFormatter in a text field cell What I would like to do next (yet not sure how to do it) is to have a context menu attached to the table view with menu items calling actions on a Foo object underneath the mouse cursor. Lets consider that the Foo class has something like the following: - (IBAction)setOneDot:(id)sender; - (IBAction)setTwoDots:(id)sender; - (IBAction)setThreeDots:(id)sender; And the context menu would have items like "One dot", "Two dots" and "Three dots" which would call those actions. The problem here is that target-action relationships can't be bound in the Interface Builder, since target is not known until the user presses right mouse on the table view. I am guessing that the best solution would be to subclass NSCell or NSTextFieldCell and then override some method to handle the mouse event? Or maybe this could be done with some sort of Cocoa Bindings trickery to have those menu items call directly on the setDots: method of the Foo class, without having to implement a separate action for each setXXXDot(s) ? How about displaying a checkmark on the menu item for the current state? On Jan 3, 2010, at 1:58 PM, Patrick Mau wrote: > Hallo Henri > > Your assumption about how formatters should work are correct. To provide a > useful answer > I have setup a mini project here, because I have stumbled over a detail I did > not now: > > http://public.me.com/pmau > > I took your approach and implemted a minimal datasource and a "Foo" object. > This is not a great example, but here's what II did not know: > > When you wire up the formatter to the text field cell in IB, > "setFormatter" is called on the TextFieldCell, which in turn will > call your formatting code withe the cell's title: > > run > [Switching to process 7123] > Running… > 2010-01-03 12:39:47.790 Formatter[7123:a0f] NSCFString Cell Title > 2010-01-03 12:39:47.810 Formatter[7123:a0f] Foo <Foo: 0x1139291d0> > 2010-01-03 12:39:47.811 Formatter[7123:a0f] Foo <Foo: 0x1151000a0> > 2010-01-03 12:39:47.811 Formatter[7123:a0f] Foo <Foo: 0x1151000b0> > > Therefore you have too prepare to receive at least one object, which is not > "Foo". > > Interestingly, I could not find that little detail in the documentation. > > If you want to return an instance Foo from your datasource, it is much more > convenient to write > your own NSCell subclass, because you can control editing and formatting much > easier. > You can even use an attached formatter that you setup in IB, passing it a > property of Foo. > > All the best, > Patrick > > > On Jan 3, 2010, at 1:47 , Henri Häkkinen wrote: > >> Hello. >> >> I have an array of custom Foo objects which I would need to display in an >> NSTableView object. I implement the data source delegate like this: >> >> - (NSInteger)numberOfRowsInTableView:(NSTableView *)tableView { >> return [arrayOfFoos count]; >> } >> >> - (id)tableView:(NSTableView *)tableView >> objectValueForTableColumn:(NSTableColumn *)tableColumn row:(NSInteger) row { >> return [arrayOfFoos objectAtIndex:row]; >> } >> >> Then I have NSFormatter subclass FooFormatter which takes in a Foo object >> and converts it to a string. This formatter object is attached to the >> formatter property of the TextFieldCell class in the NSTableView's table >> column. The FooFormatter is like this: >> >> @implementation FooFormatter >> >> - (NSString *)stringForObjectValue:(id)anObject { >> if ([anObject isKindOfClass:[Foo class]] == NO) { >> [NSException raise:NSInvalidArgumentException format:@"Wrong >> object"]; >> } >> Foo *foo = (Foo *)anObject; >> NSString *string; >> // ... convert foo into string ... >> return string; >> } >> >> @end >> >> I am assuming here that the object returned by the data source >> objectValueForTableColumn: is passed to the formatter's >> stringForObjectValue: before it is displayed in the text field cell -- this >> seems not to be the case. I would like to keep formatting of Foo objects >> separate from the data source (if possible) since I intend to implement >> multiple different FooFormatter derived classes suited for different >> situations. >> >> The Cocoa docs seem to be a little low on details on how these NSFormatter >> objects are supposed to work. Can anybody give me any insight? Would be >> appreciated. Thanks. >> >> _______________________________________________ >> >> Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) >> >> Please do not post admin requests or moderator comments to the list. >> Contact the moderators at cocoa-dev-admins(at)lists.apple.com >> >> Help/Unsubscribe/Update your Subscription: >> http://lists.apple.com/mailman/options/cocoa-dev/pmau%40me.com >> >> This email sent to p...@me.com > _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
