src/Tizen.NUI/src/internal/Layouting/LayoutController.cs

   1 /*
   2  * Copyright (c) 2019 Samsung Electronics Co., Ltd.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  *
  16  */
  17
  18 using Tizen.NUI.BaseComponents;
  19 using System.Runtime.InteropServices;
  20 using System.Collections.Generic;
  21 using System.Diagnostics;
  22 using System;
  23 using System.ComponentModel;
  24
  25 namespace Tizen.NUI
  26 {
  27     /// <summary>
  28     /// [Draft] The class that initiates the Measuring and Layouting of the tree,
  29     ///         It sets a callback that becomes the entry point into the C# Layouting.
  30     /// </summary>
  31     internal class LayoutController : Disposable
  32     {
  33         static bool LayoutDebugController = false; // Debug flag
  34
  35         [UnmanagedFunctionPointer(CallingConvention.StdCall)]
  36         internal delegate void Callback(int id);
  37
  38         event Callback _instance;
  39
  40         private Window _window;
  41
  42         Animation _coreAnimation;
  43
  44         private List<LayoutData> _layoutTransitionDataQueue;
  45
  46         private List<LayoutItem> _itemRemovalQueue;
  47
  48         /// <summary>
  49         /// Constructs a LayoutController which controls the measuring and layouting.<br />
  50         /// <param name="window">Window attach this LayoutController to.</param>
  51         /// </summary>
  52         public LayoutController(Window window) : this(Interop.LayoutController.LayoutController_New(), true)
  53         {
  54             _window = window;
  55             _instance = new Callback(Process);
  56             Interop.LayoutController.LayoutController_SetCallback(swigCPtr, _instance);
  57
  58             _layoutTransitionDataQueue = new List<LayoutData>();
  59         }
  60
  61         internal LayoutController(global::System.IntPtr cPtr, bool cMemoryOwn) : base(cPtr, cMemoryOwn)
  62         {
  63         }
  64
  65         /// <summary>
  66         /// Get the unique id of the LayoutController
  67         /// </summary>
  68         public int GetId()
  69         {
  70             return Interop.LayoutController.LayoutController_GetId(swigCPtr);
  71         }
  72
  73         /// <summary>
  74         /// Request relayout of a LayoutItem and it's parent tree.
  75         /// </summary>
  76         /// <param name="layoutItem">LayoutItem that is required to be laid out again.</param>
  77         public void RequestLayout(LayoutItem layoutItem)
  78         {
  79             // Go up the tree and mark all parents to relayout
  80             ILayoutParent layoutParent = layoutItem.GetParent();
  81             if (layoutParent != null)
  82             {
  83                 LayoutGroup layoutGroup = layoutParent as LayoutGroup;
  84                 if (layoutGroup != null && !layoutGroup.LayoutRequested)
  85                 {
  86                     layoutGroup.RequestLayout();
  87                 }
  88             }
  89         }
  90
  91         /// <summary>
  92         /// Get the Layouting animation object that transitions layouts and content.
  93         /// Use OverrideCoreAnimation to explicitly control Playback.
  94         /// </summary>
  95         /// <returns> The layouting core Animation. </returns>
  96         [EditorBrowsable(EditorBrowsableState.Never)]
  97         public Animation GetCoreAnimation()
  98         {
  99             return _coreAnimation;
 100         }
 101
 102         /// <summary>
 103         /// Set or Get Layouting core animation override property.
 104         /// Gives explicit control over the Layouting animation playback if set to True.
 105         /// Reset to False if explicit control no longer required.
 106         /// </summary>
 107         [EditorBrowsable(EditorBrowsableState.Never)]
 108         public bool OverrideCoreAnimation { get; set; } = false;
 109
 110         /// <summary>
 111         /// Add transition data for a LayoutItem to the transition stack.
 112         /// </summary>
 113         /// <param name="transitionDataEntry">Transition data for a LayoutItem.</param>
 114         internal void AddTransitionDataEntry(LayoutData transitionDataEntry)
 115         {
 116             _layoutTransitionDataQueue.Add(transitionDataEntry);
 117         }
 118
 119         /// <summary>
 120         /// Add LayoutItem to a removal stack for removal after transitions finish.
 121         /// </summary>
 122         /// <param name="itemToRemove">LayoutItem to remove.</param>
 123         internal void AddToRemovalStack(LayoutItem itemToRemove)
 124         {
 125             if (_itemRemovalQueue == null)
 126             {
 127                 _itemRemovalQueue = new List<LayoutItem>();
 128             }
 129             _itemRemovalQueue.Add(itemToRemove);
 130         }
 131
 132         /// <summary>
 133         /// Dispose Explict or Implicit
 134         /// </summary>
 135         protected override void Dispose(DisposeTypes type)
 136         {
 137             if (disposed)
 138             {
 139                 return;
 140             }
 141
 142             //Release your own unmanaged resources here.
 143             //You should not access any managed member here except static instance.
 144             //because the execution order of Finalizes is non-deterministic.
 145
 146             if (swigCPtr.Handle != global::System.IntPtr.Zero)
 147             {
 148                 Interop.LayoutController.delete_LayoutController(swigCPtr);
 149                 swigCPtr = new global::System.Runtime.InteropServices.HandleRef(null, global::System.IntPtr.Zero);
 150             }
 151
 152             base.Dispose(type);
 153         }
 154
 155         // Traverse the tree looking for a root node that is a layout.
 156         // Once found, it's children can be assigned Layouts and the Measure process started.
 157         private void FindRootLayouts(View rootNode)
 158         {
 159             if (rootNode.Layout != null)
 160             {
 161                 Debug.WriteLineIf(LayoutDebugController, "LayoutController Root found:" + rootNode.Name);
 162                 // rootNode has a layout, start measuring and layouting from here.
 163                 MeasureAndLayout(rootNode);
 164             }
 165             else
 166             {
 167                 // Search children of supplied node for a layout.
 168                 for (uint i = 0; i < rootNode.ChildCount; i++)
 169                 {
 170                     View view = rootNode.GetChildAt(i);
 171                     FindRootLayouts(view);
 172                 }
 173             }
 174         }
 175
 176         // Starts of the actual measuring and layouting from the given root node.
 177         // Can be called from multiple starting roots but in series.
 178         void MeasureAndLayout(View root)
 179         {
 180             if (root != null)
 181             {
 182                 // Get parent MeasureSpecification, this could be the Window or View with an exact size.
 183                 Container parentNode = root.GetParent();
 184                 Size2D rootSize;
 185                 Position2D rootPosition = root.Position2D;
 186                 View parentView = parentNode as View;
 187                 if (parentView != null)
 188                 {
 189                     // Get parent View's Size.  If using Legacy size negotiation then should have been set already.
 190                     rootSize = new Size2D(parentView.Size2D.Width, parentView.Size2D.Height);
 191                 }
 192                 else
 193                 {
 194                     // Parent not a View so assume it's a Layer which is the size of the window.
 195                     rootSize = new Size2D(_window.Size.Width, _window.Size.Height);
 196                 }
 197
 198                 // Determine measure specification for root.
 199                 // The root layout policy could be an exact size, be match parent or wrap children.
 200                 // If wrap children then at most it can be the root parent size.
 201                 // If match parent then should be root parent size.
 202                 // If exact then should be that size limited by the root parent size.
 203
 204                 LayoutLength width = new LayoutLength(rootSize.Width);
 205                 LayoutLength height = new LayoutLength(rootSize.Height);
 206                 MeasureSpecification.ModeType widthMode = MeasureSpecification.ModeType.Unspecified;
 207                 MeasureSpecification.ModeType heightMode = MeasureSpecification.ModeType.Unspecified;
 208
 209                 if (root.WidthSpecification >= 0)
 210                 {
 211                     // exact size provided so match width exactly
 212                     width = new LayoutLength(root.WidthSpecification);
 213                     widthMode = MeasureSpecification.ModeType.Exactly;
 214                 }
 215                 else if (root.WidthSpecification == LayoutParamPolicies.MatchParent)
 216                 {
 217
 218                     widthMode = MeasureSpecification.ModeType.Exactly;
 219                 }
 220
 221                 if (root.HeightSpecification >= 0)
 222                 {
 223                     // exact size provided so match height exactly
 224                     height = new LayoutLength(root.HeightSpecification);
 225                     heightMode = MeasureSpecification.ModeType.Exactly;
 226                 }
 227                 else if (root.HeightSpecification == LayoutParamPolicies.MatchParent)
 228                 {
 229                     heightMode = MeasureSpecification.ModeType.Exactly;
 230                 }
 231
 232                 MeasureSpecification parentWidthSpecification =
 233                     new MeasureSpecification(width, widthMode);
 234
 235                 MeasureSpecification parentHeightSpecification =
 236                     new MeasureSpecification(height, heightMode);
 237
 238                 // Start at root with it's parent's widthSpecification and heightSpecification
 239                 MeasureHierarchy(root, parentWidthSpecification, parentHeightSpecification);
 240
 241                 // Start at root which was just measured.
 242                 PerformLayout(root, new LayoutLength(rootPosition.X),
 243                                      new LayoutLength(rootPosition.Y),
 244                                      new LayoutLength(rootPosition.X) + root.Layout.MeasuredWidth.Size,
 245                                      new LayoutLength(rootPosition.Y) + root.Layout.MeasuredHeight.Size);
 246
 247                 bool readyToPlay = SetupCoreAnimation();
 248
 249                 if (readyToPlay && OverrideCoreAnimation == false)
 250                 {
 251                     PlayAnimation();
 252                 }
 253             }
 254         }
 255
 256         /// <summary>
 257         /// Entry point into the C# Layouting that starts the Processing
 258         /// </summary>
 259         private void Process(int id)
 260         {
 261             // First layer in the Window should be the default layer (index 0 )
 262             uint numberOfLayers = _window.LayerCount;
 263             for (uint layerIndex = 0; layerIndex < numberOfLayers; layerIndex++)
 264             {
 265                 Layer layer = _window.GetLayer(layerIndex);
 266                 if (layer != null)
 267                 {
 268                     for (uint i = 0; i < layer.ChildCount; i++)
 269                     {
 270                         View view = layer.GetChildAt(i);
 271                         FindRootLayouts(view);
 272                     }
 273                 }
 274             }
 275
 276         }
 277
 278         /// <summary>
 279         /// Starts measuring the tree, starting from the root layout.
 280         /// </summary>
 281         private void MeasureHierarchy(View root, MeasureSpecification widthSpec, MeasureSpecification heightSpec)
 282         {
 283             // Does this View have a layout?
 284             // Yes - measure the layout. It will call this method again for each of it's children.
 285             // No -  reached leaf or no layouts set
 286             //
 287             // If in a leaf View with no layout, it's natural size is bubbled back up.
 288
 289             if (root.Layout != null)
 290             {
 291                 root.Layout.Measure(widthSpec, heightSpec);
 292             }
 293         }
 294
 295         /// <summary>
 296         /// Performs the layouting positioning
 297         /// </summary>
 298         private void PerformLayout(View root, LayoutLength left, LayoutLength top, LayoutLength right, LayoutLength bottom)
 299         {
 300             if (root.Layout != null)
 301             {
 302                 root.Layout.Layout(left, top, right, bottom);
 303             }
 304         }
 305
 306         /// <summary>
 307         /// Play the animation.
 308         /// </summary>
 309         private void PlayAnimation()
 310         {
 311             Debug.WriteLineIf(LayoutDebugController, "LayoutController Playing, Core Duration:" + _coreAnimation.Duration);
 312             _coreAnimation.Play();
 313         }
 314
 315         private void AnimationFinished(object sender, EventArgs e)
 316         {
 317             // Iterate list of LayoutItem that were set for removal.
 318             // Now the core animation has finished their Views can be removed.
 319             if (_itemRemovalQueue != null)
 320             {
 321                 foreach (LayoutItem item in _itemRemovalQueue)
 322                 {
 323                     // Check incase the parent was already removed and the Owner was
 324                     // removed already.
 325                     if (item.Owner)
 326                     {
 327                         // Check again incase the parent has already been removed.
 328                         ILayoutParent layoutParent = item.GetParent();
 329                         LayoutGroup layoutGroup = layoutParent as LayoutGroup;
 330                         if (layoutGroup != null)
 331                         {
 332                             layoutGroup.Owner?.RemoveChild(item.Owner);
 333                         }
 334
 335                     }
 336                 }
 337                 _itemRemovalQueue.Clear();
 338                 // If LayoutItems added to stack whilst the core animation is playing
 339                 // they would have been cleared here.
 340                 // Could have another stack to be added to whilst the animation is running.
 341                 // After the running stack is cleared it can be populated with the content
 342                 // of the other stack.  Then the main removal stack iterated when AnimationFinished
 343                 // occurs again.
 344             }
 345             Debug.WriteLineIf(LayoutDebugController, "LayoutController AnimationFinished");
 346             _coreAnimation?.Clear();
 347         }
 348
 349         /// <summary>
 350         /// Set up the animation from each LayoutItems position data.
 351         /// Iterates the transition stack, adding an Animator to the core animation.
 352         /// </summary>
 353         private bool SetupCoreAnimation()
 354         {
 355             // Initialize animation for this layout run.
 356             bool animationPending = false;
 357
 358             Debug.WriteLineIf(LayoutDebugController,
 359                                "LayoutController SetupCoreAnimation for:" + _layoutTransitionDataQueue.Count);
 360
 361             if (_layoutTransitionDataQueue.Count > 0) // Something to animate
 362             {
 363                 if (!_coreAnimation)
 364                 {
 365                     _coreAnimation = new Animation();
 366                 }
 367                 _coreAnimation.EndAction = Animation.EndActions.StopFinal;
 368                 _coreAnimation.Finished += AnimationFinished;
 369
 370                 // Iterate all items that have been queued for repositioning.
 371                 foreach (LayoutData layoutPositionData in _layoutTransitionDataQueue)
 372                 {
 373                     AddAnimatorsToAnimation(layoutPositionData);
 374                 }
 375
 376                 animationPending = true;
 377
 378                 // transitions have now been applied, clear stack, ready for new transitions on
 379                 // next layout traversal.
 380                 _layoutTransitionDataQueue.Clear();
 381             }
 382             return animationPending;
 383         }
 384
 385         private void SetupAnimationForPosition(LayoutData layoutPositionData, TransitionComponents positionTransitionComponents)
 386         {
 387             // A removed item does not have a valid target position within the layout so don't try to position.
 388             if (layoutPositionData.ConditionForAnimation != TransitionCondition.Remove)
 389             {
 390                 _coreAnimation.AnimateTo(layoutPositionData.Item.Owner, "Position",
 391                             new Vector3(layoutPositionData.Left,
 392                                         layoutPositionData.Top,
 393                                         layoutPositionData.Item.Owner.Position.Z),
 394                             positionTransitionComponents.Delay,
 395                             positionTransitionComponents.Duration,
 396                             positionTransitionComponents.AlphaFunction);
 397
 398                 Debug.WriteLineIf(LayoutDebugController,
 399                                    "LayoutController SetupAnimationForPosition View:" + layoutPositionData.Item.Owner.Name +
 400                                    " left:" + layoutPositionData.Left +
 401                                    " top:" + layoutPositionData.Top +
 402                                    " delay:" + positionTransitionComponents.Delay +
 403                                    " duration:" + positionTransitionComponents.Duration);
 404             }
 405         }
 406
 407         private void SetupAnimationForSize(LayoutData layoutPositionData, TransitionComponents sizeTransitionComponents)
 408         {
 409             // Text size cant be animated so is set to it's final size.
 410             // It is due to the internals of the Text not being able to recalculate fast enough.
 411             if (layoutPositionData.Item.Owner is TextLabel || layoutPositionData.Item.Owner is TextField)
 412             {
 413                 float itemWidth = layoutPositionData.Right - layoutPositionData.Left;
 414                 float itemHeight = layoutPositionData.Bottom - layoutPositionData.Top;
 415                 // Set size directly.
 416                 layoutPositionData.Item.Owner.Size2D = new Size2D((int)itemWidth, (int)itemHeight);
 417             }
 418             else
 419             {
 420                 _coreAnimation.AnimateTo(layoutPositionData.Item.Owner, "Size",
 421                                          new Vector3(layoutPositionData.Right - layoutPositionData.Left,
 422                                                      layoutPositionData.Bottom - layoutPositionData.Top,
 423                                                      layoutPositionData.Item.Owner.Position.Z),
 424                                          sizeTransitionComponents.Delay,
 425                                          sizeTransitionComponents.Duration,
 426                                          sizeTransitionComponents.AlphaFunction);
 427
 428                 Debug.WriteLineIf(LayoutDebugController,
 429                                   "LayoutController SetupAnimationForSize View:" + layoutPositionData.Item.Owner.Name +
 430                                    " width:" + (layoutPositionData.Right - layoutPositionData.Left) +
 431                                    " height:" + (layoutPositionData.Bottom - layoutPositionData.Top) +
 432                                    " delay:" + sizeTransitionComponents.Delay +
 433                                    " duration:" + sizeTransitionComponents.Duration);
 434             }
 435         }
 436
 437         void SetupAnimationForCustomTransitions(TransitionList transitionsToAnimate, View view)
 438         {
 439             if (transitionsToAnimate?.Count > 0)
 440             {
 441                 foreach (LayoutTransition transition in transitionsToAnimate)
 442                 {
 443                     if (transition.AnimatableProperty != AnimatableProperties.Position &&
 444                         transition.AnimatableProperty != AnimatableProperties.Size)
 445                     {
 446                         _coreAnimation.AnimateTo(view,
 447                                                  transition.AnimatableProperty.ToString(),
 448                                                  transition.TargetValue,
 449                                                  transition.Animator.Delay,
 450                                                  transition.Animator.Duration,
 451                                                  transition.Animator.AlphaFunction);
 452
 453                         Debug.WriteLineIf(LayoutDebugController,
 454                                            "LayoutController SetupAnimationForCustomTransitions View:" + view.Name +
 455                                            " Property:" + transition.AnimatableProperty.ToString() +
 456                                            " delay:" + transition.Animator.Delay +
 457                                            " duration:" + transition.Animator.Duration);
 458                     }
 459                 }
 460             }
 461         }
 462
 463         /// <summary>
 464         /// Iterate transitions and replace Position Components if replacements found in list.
 465         /// </summary>
 466         private void FindAndReplaceAnimatorComponentsForProperty(TransitionList sourceTransitionList,
 467                                                                  AnimatableProperties propertyToMatch,
 468                                                                  ref TransitionComponents transitionComponentToUpdate)
 469         {
 470             foreach (LayoutTransition transition in sourceTransitionList)
 471             {
 472                 if (transition.AnimatableProperty == propertyToMatch)
 473                 {
 474                     // Matched property to animate is for the propertyToMatch so use provided Animator.
 475                     transitionComponentToUpdate = transition.Animator;
 476                 }
 477             }
 478         }
 479
 480         private TransitionComponents CreateDefaultTransitionComponent(int delay, int duration)
 481         {
 482             AlphaFunction alphaFunction = new AlphaFunction(AlphaFunction.BuiltinFunctions.Linear);
 483             return new TransitionComponents(delay, duration, alphaFunction);
 484         }
 485
 486         /// <summary>
 487         /// Sets up the main animation with the animators for each item (each layoutPositionData structure)
 488         /// </summary>
 489         private void AddAnimatorsToAnimation(LayoutData layoutPositionData)
 490         {
 491             LayoutTransition positionTransition = new LayoutTransition();
 492             LayoutTransition sizeTransition = new LayoutTransition();
 493             TransitionCondition conditionForAnimators = layoutPositionData.ConditionForAnimation;
 494
 495             // LayoutChanged transitions overrides ChangeOnAdd and ChangeOnRemove as siblings will
 496             // reposition to the new layout not to the insertion/removal of a sibling.
 497             if (layoutPositionData.ConditionForAnimation.HasFlag(TransitionCondition.LayoutChanged))
 498             {
 499                 conditionForAnimators = TransitionCondition.LayoutChanged;
 500             }
 501
 502             // Set up a default transitions, will be overwritten if inherited from parent or set explicitly.
 503             TransitionComponents positionTransitionComponents = CreateDefaultTransitionComponent(0, 300);
 504             TransitionComponents sizeTransitionComponents = CreateDefaultTransitionComponent(0, 300);
 505
 506             bool matchedCustomTransitions = false;
 507
 508
 509             TransitionList transitionsForCurrentCondition = new TransitionList();
 510             // Note, Transitions set on View rather than LayoutItem so if the Layout changes the transition persist.
 511
 512             // Check if item to animate has it's own Transitions for this condition.
 513             // If a key exists then a List of atleast 1 transition exists.
 514             if (layoutPositionData.Item.Owner.LayoutTransitions.ContainsKey(conditionForAnimators))
 515             {
 516                 // Child has transitions for the condition
 517                 matchedCustomTransitions = layoutPositionData.Item.Owner.LayoutTransitions.TryGetValue(conditionForAnimators, out transitionsForCurrentCondition);
 518             }
 519
 520             if (!matchedCustomTransitions)
 521             {
 522                 // Inherit parent transitions as none already set on View for the condition.
 523                 ILayoutParent layoutParent = layoutPositionData.Item.GetParent();
 524                 if (layoutParent != null)
 525                 {
 526                     // Item doesn't have it's own transitions for this condition so copy parents if
 527                     // has a parent with transitions.
 528                     LayoutGroup layoutGroup = layoutParent as LayoutGroup;
 529                     TransitionList parentTransitionList;
 530                     // Note TryGetValue returns null if key not matched.
 531                     if (layoutGroup != null && layoutGroup.Owner.LayoutTransitions.TryGetValue(conditionForAnimators, out parentTransitionList))
 532                     {
 533                         // Copy parent transitions to temporary TransitionList. List contains transitions for the current condition.
 534                         LayoutTransitionsHelper.CopyTransitions(parentTransitionList,
 535                                                                 transitionsForCurrentCondition);
 536                     }
 537                 }
 538             }
 539
 540
 541             // Position/Size transitions can be displayed for a layout changing to another layout or an item being added or removed.
 542
 543             // There can only be one position transition and one size position, they will be replaced if set multiple times.
 544             // transitionsForCurrentCondition represent all non position (custom) properties that should be animated.
 545
 546             // Search for Position property in the transitionsForCurrentCondition list of custom transitions,
 547             // and only use the particular parts of the animator as custom transitions should not effect all parameters of Position.
 548             // Typically Delay, Duration and Alphafunction can be custom.
 549             FindAndReplaceAnimatorComponentsForProperty(transitionsForCurrentCondition,
 550                                                         AnimatableProperties.Position,
 551                                                         ref positionTransitionComponents);
 552
 553             // Size
 554             FindAndReplaceAnimatorComponentsForProperty(transitionsForCurrentCondition,
 555                                                         AnimatableProperties.Size,
 556                                                         ref sizeTransitionComponents);
 557
 558             // Add animators to the core Animation,
 559
 560             SetupAnimationForCustomTransitions(transitionsForCurrentCondition, layoutPositionData.Item.Owner);
 561
 562             SetupAnimationForPosition(layoutPositionData, positionTransitionComponents);
 563
 564             SetupAnimationForSize(layoutPositionData, sizeTransitionComponents);
 565         }
 566
 567     } // class LayoutController
 568 } // namespace Tizen.NUI