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Discussion\n\nAuto Layout\n\n\nStack Views, FTW (Auto Layout without constraints) (New in iOS 9, similar to what\u2019s available in watchOS and NSStackView, which is available from OS X 10.9)\nUILayoutGuide\n\n\nNew in iOS 9\nDefines a rectangular geometry that can interact with Auto Layout\nEliminates the need (in many cases, at least) for views that are included solely for layout purposes (container views, spacing views, etc)\nViews can still provide a greater degree of encapsulation\nProvide anchors that can be used to generate constraints\n\n\nAnatomy of constraints\n\n\nThe layout of your view hierarchy is defined as a series of linear equations. Each constraint represents a single equation. Your goal is to declare a series of equations that has one and only one possible solution.\nTwo basic types of attributes\n\n\nSize attributes (for example, Height and Width)\nLocation attributes (for example, Leading, Left, and Top)\nThe following rules apply:\n\n\nYou cannot constrain a size attribute to a location attribute.\nYou cannot assign constant values to location attributes.\nYou cannot use a nonidentity multiplier (a value other than 1.0) with location attributes.\nFor location attributes, you cannot constrain vertical attributes to horizontal attributes.\nFor location attributes, you cannot constrain Leading or Trailing attributes to Left or Right attributes.\n\n\nRule of Thumb for clarity\n\n\nWhole number multipliers are favored over fractional multipliers.\n\n\nPositive constants are favored over negative constants.\nWherever possible, views should appear in layout order: leading to trailing, top to bottom.\nConstraint Priorities\n\n\n1000 is required\n< 1000 is optional\n\n\nIntrinsic Content Size\n\n\nContent Compression Resistance\nContent Hugging\n\n\nDebugging Auto Layout\n\n\nError Types\n\n\nUnsatisfiable Layouts. Your layout has no valid solution.\n\n\nUsually 2 or more required constraints conflict\n\n\n\n\nAmbiguous Layouts. Your layout has two or more possible solutions.\n\n * Need additional constraints\n\n\n\nconflicting optional constraints\n\n\nLogical Errors. There is a bug in your layout logic.\n\n\nTips and Tricks\n\n\ntake advantage of the logs\nuse meaning identifiers on views and constraints\nDebug > View Debugging > Show Alignment Rectangles\n\n\n\n\n\nPicks\n\nDarryl\n\n\nApp Cooker & App Taster - Prototyping tool for Watch, iPhone and iPad apps\n\n\n\nNolan\n\n\nWe Haven\u2019t Forgotten How To Program Enough\n\n\n\nJohn\n\n\nMysteries of Auto Layout Part 1 and Part 2 from WWDC 2015\nMy choice for a smart watch, Fitbit Blaze