我在使用Cocoa Autolayout时遇到了一些问题。
我有一个窗口，我（以编程方式）添加了一个NSTableView（及其NSScrollView）。到现在为止一切正常。我可以调整窗口大小，表格也可以正确调整大小。
这是我使用的代码。
MyListViewController *viewController = [[MyListViewController alloc] initWithNibName:@"ListView" bundle:nil];
[self.mainContentView addSubview:viewController.view];
[viewController.view setTranslatesAutoresizingMaskIntoConstraints:NO];
[self.mainContentView addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[insertedView]|"
options:0
metrics:nil
views:@{@"insertedView" :viewController.view}]];
NSArray *verticalConstraints = [NSLayoutConstraint constraintsWithVisualFormat:@"V:|[insertedView]|"
options:0
metrics:nil
views:@{@"insertedView" :viewController.view}];
[self.mainContentView addConstraints:verticalConstraints];
现在，我想在运行时添加（和删除）位于表顶部的另一个视图。
该视图是具有
NSPredicateEditor的NSScrollView。明确说明：当您在搜索字段中键入内容，并且带有可能的搜索选项的视图出现在主窗口中时，我正在尝试实现与Finder相同的行为。我这样处理：
AdvancedFilterViewController *viewController = [[AdvancedFilterViewController alloc] initWithNibName:@"AdvancedFilterView" bundle:nil];
[self.mainContentView addSubview:viewController.view];
[viewController.view setTranslatesAutoresizingMaskIntoConstraints:NO];
[self.mainContentView addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|[insertedView]|"
options:0
metrics:nil
views:@{@"insertedView" :viewController.view}]];
[self.mainContentView addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|[insertedView(<=225)][prevView]|" // >= size of one row, <= size of 8 + 1 rows
options:0
metrics:nil
views:@{@"insertedView" :viewController.view, @"prevView" : self.listView.view}]];
我希望至少有一行谓词（25分）可见。当用户按下加号按钮时，就会出现更多视图（滚动视图应适应其大小）。经过几行（我决定为9）后，滚动条应开始出现，并且窗口中的主视图应停止缩小。
问题是，当我插入过滤器视图时，它的大小几乎为零（例如1点）。或者，如果我添加最小点数为25点，则视图是可见的，但添加行只会增加滚动视图的“内部大小”，因此会出现滚动条（但滚动视图不会增长并且不会使列表视图缩小） 。
我希望我能正确解释问题。
编辑：
从答案中得到启发，我实现了代表：
- (void)ruleEditorRowsDidChange:(NSNotification *)notification
{
//handle resizing of the view
[self.predicateEditorHeight setConstant:[self.predicateEditor numberOfRows] * self.predicateEditor.rowHeight];
}
其中，
self.predicateEditorHeight是对IBOutlet高度的约束的NSScrollView。然后在封闭的
NSWindowController中，当我添加谓词编辑器视图时，我还添加了对NSTableView相对于谓词视图的比例的约束。通过这种方式（因为我将其设置为0.3），滚动视图可以增长到某个点，然后，此后必须使用其滚动条。
关于约束，我仍然有一些问题：
例如，当我在编辑器中添加太多行时，我得到
2014-04-26 09:38:27.769 MyApp[2531:303] Unable to simultaneously satisfy constraints:
(
"<NSLayoutConstraint:0x60000029dc40 V:[NSView:0x60000013fb80]-(0)-| (Names: '|':NSView:0x60000013e500 )>",
"<NSLayoutConstraint:0x60000029dbf0 V:[NSView:0x600000320b40]-(0)-[NSView:0x60000013fb80]>",
"<NSLayoutConstraint:0x60000029dc90 NSView:0x60000013fb80.height >= 0.3*NSView:0x600000320b40.height>",
"<NSAutoresizingMaskLayoutConstraint:0x608000288b60 h=--& v=--& V:[NSView:0x60000013e500(360)]>",
"<NSLayoutConstraint:0x60000029dba0 V:|-(0)-[NSView:0x600000320b40] (Names: '|':NSView:0x60000013e500 )>",
"<NSLayoutConstraint:0x60000029d1a0 V:[NSView:0x600000320f00(275)]>",
"<NSLayoutConstraint:0x60000029d420 V:[NSView:0x600000320f00]-(0)-| (Names: '|':NSView:0x600000320b40 )>",
"<NSLayoutConstraint:0x60000029d510 V:[NSView:0x600000320dc0]-(0)-[NSView:0x600000320f00]>",
"<NSLayoutConstraint:0x60000029d330 V:|-(0)-[NSView:0x600000320dc0] (Names: '|':NSView:0x600000320b40 )>",
"<NSLayoutConstraint:0x60000029d060 V:[NSButton:0x6000001569a0'Search']-(4)-| (Names: '|':NSView:0x600000320dc0 )>",
"<NSLayoutConstraint:0x60000029d0b0 V:|-(5)-[NSButton:0x6000001569a0'Search'] (Names: '|':NSView:0x600000320dc0 )>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x60000029d060 V:[NSButton:0x6000001569a0'Search']-(4)-| (Names: '|':NSView:0x600000320dc0 )>
2014-04-26 09:38:27.770 MyApp[2531:303] Unable to simultaneously satisfy constraints:
(
"<NSLayoutConstraint:0x60000029dc40 V:[NSView:0x60000013fb80]-(0)-| (Names: '|':NSView:0x60000013e500 )>",
"<NSLayoutConstraint:0x60000029dbf0 V:[NSView:0x600000320b40]-(0)-[NSView:0x60000013fb80]>",
"<NSLayoutConstraint:0x60000029dc90 NSView:0x60000013fb80.height >= 0.3*NSView:0x600000320b40.height>",
"<NSAutoresizingMaskLayoutConstraint:0x608000288b60 h=--& v=--& V:[NSView:0x60000013e500(360)]>",
"<NSLayoutConstraint:0x60000029dba0 V:|-(0)-[NSView:0x600000320b40] (Names: '|':NSView:0x60000013e500 )>",
"<NSLayoutConstraint:0x60000029d1a0 V:[NSView:0x600000320f00(275)]>",
"<NSLayoutConstraint:0x60000029d420 V:[NSView:0x600000320f00]-(0)-| (Names: '|':NSView:0x600000320b40 )>",
"<NSLayoutConstraint:0x60000029d510 V:[NSView:0x600000320dc0]-(0)-[NSView:0x600000320f00]>",
"<NSLayoutConstraint:0x60000029d330 V:|-(0)-[NSView:0x600000320dc0] (Names: '|':NSView:0x600000320b40 )>",
"<NSLayoutConstraint:0x60000029d100 V:|-(4)-[NSButton:0x6000001564d0] (Names: '|':NSView:0x600000320dc0 )>",
"<NSLayoutConstraint:0x60000029d150 V:[NSButton:0x6000001564d0]-(5)-| (Names: '|':NSView:0x600000320dc0 )>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x60000029d150 V:[NSButton:0x6000001564d0]-(5)-| (Names: '|':NSView:0x600000320dc0 )>
2014-04-26 09:38:27.775 MyApp[2531:303] Unable to simultaneously satisfy constraints:
(
"<NSLayoutConstraint:0x60000029cf70 V:[NSTextField:0x600000198940]-(4)-| (Names: '|':NSView:0x600000320dc0 )>",
"<NSLayoutConstraint:0x60000029cfc0 V:|-(4)-[NSTextField:0x600000198940] (Names: '|':NSView:0x600000320dc0 )>",
"<NSLayoutConstraint:0x60000029dc40 V:[NSView:0x60000013fb80]-(0)-| (Names: '|':NSView:0x60000013e500 )>",
"<NSLayoutConstraint:0x60000029dbf0 V:[NSView:0x600000320b40]-(0)-[NSView:0x60000013fb80]>",
"<NSLayoutConstraint:0x60000029dc90 NSView:0x60000013fb80.height >= 0.3*NSView:0x600000320b40.height>",
"<NSAutoresizingMaskLayoutConstraint:0x608000288b60 h=--& v=--& V:[NSView:0x60000013e500(360)]>",
"<NSLayoutConstraint:0x60000029dba0 V:|-(0)-[NSView:0x600000320b40] (Names: '|':NSView:0x60000013e500 )>",
"<NSLayoutConstraint:0x60000029d1a0 V:[NSView:0x600000320f00(275)]>",
"<NSLayoutConstraint:0x60000029d420 V:[NSView:0x600000320f00]-(0)-| (Names: '|':NSView:0x600000320b40 )>",
"<NSLayoutConstraint:0x60000029d510 V:[NSView:0x600000320dc0]-(0)-[NSView:0x600000320f00]>",
"<NSLayoutConstraint:0x60000029d330 V:|-(0)-[NSView:0x600000320dc0] (Names: '|':NSView:0x600000320b40 )>"
)
Will attempt to recover by breaking constraint
<NSLayoutConstraint:0x60000029cf70 V:[NSTextField:0x600000198940]-(4)-| (Names: '|':NSView:0x600000320dc0 )>
最佳答案
您必须“通知”父视图，内部视图将调整大小。我的方法是观察谓词由其代表增长和收缩：
- (void)ruleEditorRowsDidChange:(NSNotification *)notification{
NSInteger newRowCount = [_predicateEditor numberOfRows];
NSInteger rowHeight = [_predicateEditor rowHeight];
// Send a notification - size changes
NSRect newFrame = self.view.frame;
newFrame.size.height = 30 + newRowCount*rowHeight;
[[NSNotificationCenter defaultCenter]postNotificationName:@"RowsDidChange" object:[NSValue valueWithRect:newFrame]];
[[_heightConstraint animator] setConstant:rowHeight*newRowCount];
}
在父级ViewController中有一个“观察者”来观察大小变化：
[[NSNotificationCenter defaultCenter]addObserverForName:@"RowsDidChange"
object:nil
queue:nil
usingBlock:^(NSNotification * notification){
NSValue *value = (NSValue*)notification.object;
NSRect rectValue = [value rectValue];
NSRect newContentRect = self.resultsView.frame;
newContentRect.size.height = self.resultsView.frame.size.height - rectValue.size.height;
newContentRect.size.width = self.resultsView.frame.size.width;
// Set new height to the mainViewController
[[self.mainViewController view] setFrame:newContentRect];
}];
您不需要发送通知，也可以向您的父级viewcontroller发送一些委托方法。
祝好运。
关于macos - cocoa 自动布局:在运行时以编程方式插入(和删除) View ，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/22966386/