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I’ve created a custom NSSlider and it looks wonderful. The problem is that when I set an action and target either in the interface builder or by code it doesnt work. The slider will not perform the action. Please help! Here is my code:

@implementation progressSliderCell


@implementation progressSlider


You should probably implement your copyWithZone: method to actually create a copy. The way you have it, it creates a new object, but copies no attributes over.

Since you don’t have any extra attributes to copy, you can probably just call through to super, or just remove your override altogether and let [[NSSliderCell take care of making copies.

There’s probably no need to implement performClick: either.

Nor sendAction:toTarget:. Nor dealloc on the NSSlider subclass. If you aren’t changing the parent’s behavior, you don’t have to implement the method.

I tried to use this subclass in one of my projects, and it doesn’t work. I put the interface declarations in, and it doesn’t give any errors, but the slider doesn’t work, either. What am I doing wrong? I put in the declarations in a .h file, and declared the nsimage instances, and then added it with the nsslider to the IB file (and applied it to the slider). What am I missing?

Because of the way IB creates objects, you have to use a custom view and change its class to progressSlider (lowercase class names are about as far from the standard as you can get, by the way). If you change an NSSlider’s class, it will make it a progressSlider – but the slider cell will still be an NSSliderCell. Alternatively, you could add code like this (modified from one of my own projects) to change the necessary NSSliderCells to progressSliderCells. –JediKnil

// Within the view class…

JediKnil’s approach is a good and sound trick. However, it shouldn’t hard-code the restoring of the class. Instead, before calling NSKeyedUnarchiver’s -setClass:forClassName: it should first call -classForClassName: and store the returned Class. Then when restoring, call -setClass:forClassName: passing the saved-off Class as the 1st argument. In the NSUnarchiver case, call -classNameDecodedForArchiveClassName: to save off the NSString* of the class name, then pass that back to -decodeClassName:asClassName: when restoring. So, good approach, just don’t assume what you’re restoring is what you wanted to replace… save off the old value, set it to the new, then restore the old value.