如何通知NSObjectController的任何绑定更改

时间:2014-01-10 11:20:57

标签: macos cocoa cocoa-bindings nsobjectcontroller

我有一个NSView,其中所有控件都已使用Interface Builder中的NSObjectController绑定到模型对象。

这可以正常工作。现在,我希望只要对这些绑定的任何进行更改,我的NSViewController就会收到通知。这可能吗?如果是这样,怎么样?

1 个答案:

答案 0 :(得分:0)

我最终使用KVO观察了我的模型类的成员。为了自动化这个过程(这样我就不必为每个模型的每个成员编写代码来执行此操作),我这样做了:

static void *myModelObserverContextPointer = &myModelObserverContextPointer;

- (void)establishObserversForPanelModel:(FTDisclosurePanelModel *)panelModel {

    // Add observers for all the model's class members.
    //
    // The member variables are updated automatically using bindings as the user makes
    // adjustments to the user interface. By doing this we can therefore be informed
    // of any changes that the user is making without having to have a target action for
    // each control.

    unsigned int count;
    objc_property_t *props = class_copyPropertyList([panelModel class], &count);

    for (int i = 0; i < count; ++i){
        NSString *propName = [NSString stringWithUTF8String:property_getName(props[i])];
        [panelModel addObserver:self forKeyPath:propName options:0 context:&myModelObserverContextPointer];
    }
}

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {

    // Check for insertions/deletions to the model

    if (context == myModelObserverContextPointer) {
        if ([_delegate respondsToSelector:@selector(changeMadeToPanelModel:keyPath:)]) {
            [_delegate changeMadeToPanelModel:object keyPath:keyPath];
        }
    }
    else
        [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];

}