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.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 through children from the provided root.
 156         // If a child has no layout but is a pure View then assign a default layout and continue traversal.
 157         // If child has no layout and not a pure View then assign a LayoutItem that terminates the layouting (leaf),
 158         private void AutomaticallyAssignLayouts(View rootNode)
 159         {
 160             for (uint i = 0; i < rootNode.ChildCount; i++)
 161             {
 162                 View view = rootNode.GetChildAt(i);
 163                 if (view.Layout == null )
 164                 {
 165                     view.Layout = new AbsoluteLayout();
 166                     AutomaticallyAssignLayouts(rootNode);
 167                 }
 168             }
 169         }
 170
 171         // Traverse the tree looking for a root node that is a layout.
 172         // Once found, it's children can be assigned Layouts and the Measure process started.
 173         private void FindRootLayouts(View rootNode)
 174         {
 175             if (rootNode.Layout != null)
 176             {
 177                 Debug.WriteLineIf( LayoutDebugController, "LayoutController Root found:" + rootNode.Name);
 178                 // rootNode has a layout, ensure all children have default layouts or layout items.
 179                 AutomaticallyAssignLayouts(rootNode);
 180                 // rootNode has a layout, start measuring and layouting from here.
 181                 MeasureAndLayout(rootNode);
 182             }
 183             else
 184             {
 185                 // Search children of supplied node for a layout.
 186                 for (uint i = 0; i < rootNode.ChildCount; i++)
 187                 {
 188                     View view = rootNode.GetChildAt(i);
 189                     FindRootLayouts(view);
 190                 }
 191             }
 192         }
 193
 194         // Starts of the actual measuring and layouting from the given root node.
 195         // Can be called from multiple starting roots but in series.
 196         void MeasureAndLayout(View root)
 197         {
 198             if (root !=null)
 199             {
 200                 // Get parent MeasureSpecification, this could be the Window or View with an exact size.
 201                 Container parentNode = root.GetParent();
 202                 Size2D rootSize;
 203                 Position2D rootPosition = root.Position2D;
 204                 View parentView = parentNode as View;
 205                 if (parentView)
 206                 {
 207                     // Get parent View's Size.  If using Legacy size negotiation then should have been set already.
 208                     rootSize = new Size2D(parentView.Size2D.Width, parentView.Size2D.Height);
 209                 }
 210                 else
 211                 {
 212                     // Parent not a View so assume it's a Layer which is the size of the window.
 213                     rootSize = new Size2D(_window.Size.Width, _window.Size.Height);
 214                 }
 215
 216                 // Determine measure specification for root.
 217                 // The root layout policy could be an exact size, be match parent or wrap children.
 218                 // If wrap children then at most it can be the root parent size.
 219                 // If match parent then should be root parent size.
 220                 // If exact then should be that size limited by the root parent size.
 221
 222                 LayoutLength width = new LayoutLength(rootSize.Width);
 223                 LayoutLength height = new LayoutLength(rootSize.Height);
 224                 MeasureSpecification.ModeType widthMode = MeasureSpecification.ModeType.Unspecified;
 225                 MeasureSpecification.ModeType heightMode = MeasureSpecification.ModeType.Unspecified;
 226
 227                 if ( root.WidthSpecification >= 0 )
 228                 {
 229                     // exact size provided so match width exactly
 230                     width = new LayoutLength(root.WidthSpecification);
 231                     widthMode = MeasureSpecification.ModeType.Exactly;
 232                 }
 233                 else if (root.WidthSpecification == LayoutParamPolicies.MatchParent)
 234                 {
 235
 236                     widthMode = MeasureSpecification.ModeType.Exactly;
 237                 }
 238
 239                 if (root.HeightSpecification >= 0 )
 240                 {
 241                     // exact size provided so match height exactly
 242                     height = new LayoutLength(root.HeightSpecification);
 243                     heightMode = MeasureSpecification.ModeType.Exactly;
 244                 }
 245                 else if (root.HeightSpecification == LayoutParamPolicies.MatchParent)
 246                 {
 247                     heightMode = MeasureSpecification.ModeType.Exactly;
 248                 }
 249
 250                 MeasureSpecification parentWidthSpecification =
 251                     new MeasureSpecification( width, widthMode);
 252
 253                 MeasureSpecification parentHeightSpecification =
 254                     new MeasureSpecification( height, heightMode);
 255
 256                 // Start at root with it's parent's widthSpecification and heightSpecification
 257                 MeasureHierarchy(root, parentWidthSpecification, parentHeightSpecification);
 258
 259                 // Start at root which was just measured.
 260                 PerformLayout( root, new LayoutLength(rootPosition.X),
 261                                      new LayoutLength(rootPosition.Y),
 262                                      new LayoutLength(rootPosition.X) + root.Layout.MeasuredWidth.Size,
 263                                      new LayoutLength(rootPosition.Y) + root.Layout.MeasuredHeight.Size );
 264
 265                 bool readyToPlay = SetupCoreAnimation();
 266
 267                 if (readyToPlay && OverrideCoreAnimation==false)
 268                 {
 269                     PlayAnimation();
 270                 }
 271             }
 272         }
 273
 274         /// <summary>
 275         /// Entry point into the C# Layouting that starts the Processing
 276         /// </summary>
 277         private void Process(int id)
 278         {
 279             // First layer in the Window should be the default layer (index 0 )
 280             uint numberOfLayers = _window.LayerCount;
 281             for (uint layerIndex = 0; layerIndex < numberOfLayers; layerIndex++)
 282             {
 283                 Layer layer = _window.GetLayer(layerIndex);
 284                 if (layer)
 285                 {
 286                     for (uint i = 0; i < layer.ChildCount; i++)
 287                     {
 288                         View view = layer.GetChildAt(i);
 289                         FindRootLayouts(view);
 290                     }
 291                 }
 292             }
 293
 294         }
 295
 296         /// <summary>
 297         /// Starts measuring the tree, starting from the root layout.
 298         /// </summary>
 299         private void MeasureHierarchy(View root, MeasureSpecification widthSpec, MeasureSpecification heightSpec)
 300         {
 301             // Does this View have a layout?
 302             // Yes - measure the layout. It will call this method again for each of it's children.
 303             // No -  reached leaf or no layouts set
 304             //
 305             // If in a leaf View with no layout, it's natural size is bubbled back up.
 306
 307             if (root.Layout != null)
 308             {
 309                 root.Layout.Measure(widthSpec, heightSpec);
 310             }
 311         }
 312
 313         /// <summary>
 314         /// Performs the layouting positioning
 315         /// </summary>
 316         private void PerformLayout(View root, LayoutLength left, LayoutLength top, LayoutLength right, LayoutLength bottom)
 317         {
 318             if(root.Layout != null)
 319             {
 320                 root.Layout.Layout(left, top, right, bottom);
 321             }
 322         }
 323
 324         /// <summary>
 325         /// Play the animation.
 326         /// </summary>
 327         private void PlayAnimation()
 328         {
 329             Debug.WriteLineIf( LayoutDebugController, "LayoutController Playing, Core Duration:" + _coreAnimation.Duration);
 330             _coreAnimation.Play();
 331         }
 332
 333         private void AnimationFinished(object sender, EventArgs e)
 334         {
 335             // Iterate list of LayoutItem that were set for removal.
 336             // Now the core animation has finished their Views can be removed.
 337             if (_itemRemovalQueue != null)
 338             {
 339                 foreach (LayoutItem item in _itemRemovalQueue)
 340                 {
 341                     // Check incase the parent was already removed and the Owner was
 342                     // removed already.
 343                     if (item.Owner)
 344                     {
 345                         // Check again incase the parent has already been removed.
 346                         ILayoutParent layoutParent = item.GetParent();
 347                         LayoutGroup layoutGroup = layoutParent as LayoutGroup;
 348                         if (layoutGroup !=null)
 349                         {
 350                             layoutGroup.Owner?.RemoveChild(item.Owner);
 351                         }
 352
 353                     }
 354                 }
 355                 _itemRemovalQueue.Clear();
 356                 // If LayoutItems added to stack whilst the core animation is playing
 357                 // they would have been cleared here.
 358                 // Could have another stack to be added to whilst the animation is running.
 359                 // After the running stack is cleared it can be populated with the content
 360                 // of the other stack.  Then the main removal stack iterated when AnimationFinished
 361                 // occurs again.
 362             }
 363             Debug.WriteLineIf( LayoutDebugController, "LayoutController AnimationFinished");
 364             _coreAnimation?.Clear();
 365         }
 366
 367         /// <summary>
 368         /// Set up the animation from each LayoutItems position data.
 369         /// Iterates the transition stack, adding an Animator to the core animation.
 370         /// </summary>
 371         private bool SetupCoreAnimation()
 372         {
 373             // Initialize animation for this layout run.
 374             bool animationPending = false;
 375
 376             Debug.WriteLineIf( LayoutDebugController,
 377                                "LayoutController SetupCoreAnimation for:" + _layoutTransitionDataQueue.Count);
 378
 379             if (_layoutTransitionDataQueue.Count > 0 ) // Something to animate
 380             {
 381                 if (!_coreAnimation)
 382                 {
 383                     _coreAnimation = new Animation();
 384                 }
 385                 _coreAnimation.EndAction = Animation.EndActions.StopFinal;
 386                 _coreAnimation.Finished += AnimationFinished;
 387
 388                 // Iterate all items that have been queued for repositioning.
 389                 foreach (LayoutData layoutPositionData in _layoutTransitionDataQueue)
 390                 {
 391                     AddAnimatorsToAnimation(layoutPositionData);
 392                 }
 393
 394                 animationPending = true;
 395
 396                 // transitions have now been applied, clear stack, ready for new transitions on
 397                 // next layout traversal.
 398                 _layoutTransitionDataQueue.Clear();
 399             }
 400             return animationPending;
 401         }
 402
 403         private void SetupAnimationForPosition(LayoutData layoutPositionData, TransitionComponents positionTransitionComponents)
 404         {
 405             // A removed item does not have a valid target position within the layout so don't try to position.
 406             if( layoutPositionData.ConditionForAnimation != TransitionCondition.Remove )
 407             {
 408                 _coreAnimation.AnimateTo(layoutPositionData.Item.Owner, "Position",
 409                             new Vector3(layoutPositionData.Left,
 410                                         layoutPositionData.Top,
 411                                         layoutPositionData.Item.Owner.Position.Z),
 412                             positionTransitionComponents.Delay,
 413                             positionTransitionComponents.Duration,
 414                             positionTransitionComponents.AlphaFunction );
 415
 416                 Debug.WriteLineIf( LayoutDebugController,
 417                                    "LayoutController SetupAnimationForPosition View:" + layoutPositionData.Item.Owner.Name +
 418                                    " left:" + layoutPositionData.Left +
 419                                    " top:" + layoutPositionData.Top +
 420                                    " delay:" + positionTransitionComponents.Delay +
 421                                    " duration:" + positionTransitionComponents.Duration );
 422             }
 423         }
 424
 425         private void SetupAnimationForSize(LayoutData layoutPositionData, TransitionComponents sizeTransitionComponents)
 426         {
 427             // Text size cant be animated so is set to it's final size.
 428             // It is due to the internals of the Text not being able to recalculate fast enough.
 429             if (layoutPositionData.Item.Owner is TextLabel || layoutPositionData.Item.Owner is TextField)
 430             {
 431                 float itemWidth = layoutPositionData.Right-layoutPositionData.Left;
 432                 float itemHeight = layoutPositionData.Bottom-layoutPositionData.Top;
 433                 // Set size directly.
 434                 layoutPositionData.Item.Owner.Size2D = new Size2D((int)itemWidth, (int)itemHeight);
 435             }
 436             else
 437             {
 438                 _coreAnimation.AnimateTo(layoutPositionData.Item.Owner, "Size",
 439                                          new Vector3(layoutPositionData.Right-layoutPositionData.Left,
 440                                                      layoutPositionData.Bottom-layoutPositionData.Top,
 441                                                      layoutPositionData.Item.Owner.Position.Z),
 442                                          sizeTransitionComponents.Delay,
 443                                          sizeTransitionComponents.Duration,
 444                                          sizeTransitionComponents.AlphaFunction);
 445
 446                 Debug.WriteLineIf( LayoutDebugController,
 447                                   "LayoutController SetupAnimationForSize View:" + layoutPositionData.Item.Owner.Name +
 448                                    " width:" + (layoutPositionData.Right-layoutPositionData.Left) +
 449                                    " height:" + (layoutPositionData.Bottom-layoutPositionData.Top) +
 450                                    " delay:" + sizeTransitionComponents.Delay +
 451                                    " duration:" + sizeTransitionComponents.Duration );
 452             }
 453         }
 454
 455         void SetupAnimationForCustomTransitions(TransitionList transitionsToAnimate, View view )
 456         {
 457             if (transitionsToAnimate?.Count > 0)
 458             {
 459                 foreach (LayoutTransition transition in transitionsToAnimate)
 460                 {
 461                     if ( transition.AnimatableProperty != AnimatableProperties.Position &&
 462                         transition.AnimatableProperty != AnimatableProperties.Size )
 463                     {
 464                         _coreAnimation.AnimateTo(view,
 465                                                  transition.AnimatableProperty.ToString(),
 466                                                  transition.TargetValue,
 467                                                  transition.Animator.Delay,
 468                                                  transition.Animator.Duration,
 469                                                  transition.Animator.AlphaFunction );
 470
 471                         Debug.WriteLineIf( LayoutDebugController,
 472                                            "LayoutController SetupAnimationForCustomTransitions View:" + view.Name +
 473                                            " Property:" + transition.AnimatableProperty.ToString() +
 474                                            " delay:" + transition.Animator.Delay +
 475                                            " duration:" + transition.Animator.Duration );
 476                     }
 477                 }
 478             }
 479         }
 480
 481         /// <summary>
 482         /// Iterate transitions and replace Position Components if replacements found in list.
 483         /// </summary>
 484         private void FindAndReplaceAnimatorComponentsForProperty(TransitionList sourceTransitionList,
 485                                                                  AnimatableProperties propertyToMatch,
 486                                                                  ref TransitionComponents transitionComponentToUpdate)
 487         {
 488             foreach( LayoutTransition transition in sourceTransitionList)
 489             {
 490                 if (transition.AnimatableProperty == propertyToMatch)
 491                 {
 492                     // Matched property to animate is for the propertyToMatch so use provided Animator.
 493                     transitionComponentToUpdate = transition.Animator;
 494                 }
 495             }
 496         }
 497
 498         private TransitionComponents CreateDefaultTransitionComponent( int delay, int duration )
 499         {
 500             AlphaFunction alphaFunction = new AlphaFunction(AlphaFunction.BuiltinFunctions.Linear);
 501             return new TransitionComponents(delay, duration, alphaFunction);
 502         }
 503
 504         /// <summary>
 505         /// Sets up the main animation with the animators for each item (each layoutPositionData structure)
 506         /// </summary>
 507         private void AddAnimatorsToAnimation( LayoutData layoutPositionData )
 508         {
 509             LayoutTransition positionTransition = new LayoutTransition();
 510             LayoutTransition sizeTransition = new LayoutTransition();
 511             TransitionCondition conditionForAnimators = layoutPositionData.ConditionForAnimation;
 512
 513             // LayoutChanged transitions overrides ChangeOnAdd and ChangeOnRemove as siblings will
 514             // reposition to the new layout not to the insertion/removal of a sibling.
 515             if (layoutPositionData.ConditionForAnimation.HasFlag(TransitionCondition.LayoutChanged))
 516             {
 517                 conditionForAnimators = TransitionCondition.LayoutChanged;
 518             }
 519
 520             // Set up a default transitions, will be overwritten if inherited from parent or set explicitly.
 521             TransitionComponents positionTransitionComponents = CreateDefaultTransitionComponent(0, 300);
 522             TransitionComponents sizeTransitionComponents = CreateDefaultTransitionComponent(0, 300);
 523
 524             bool matchedCustomTransitions = false;
 525
 526
 527             TransitionList transitionsForCurrentCondition = new TransitionList();
 528             // Note, Transitions set on View rather than LayoutItem so if the Layout changes the transition persist.
 529
 530             // Check if item to animate has it's own Transitions for this condition.
 531             // If a key exists then a List of atleast 1 transition exists.
 532             if (layoutPositionData.Item.Owner.LayoutTransitions.ContainsKey(conditionForAnimators))
 533             {
 534                 // Child has transitions for the condition
 535                 matchedCustomTransitions = layoutPositionData.Item.Owner.LayoutTransitions.TryGetValue(conditionForAnimators, out transitionsForCurrentCondition);
 536             }
 537
 538             if (!matchedCustomTransitions)
 539             {
 540                 // Inherit parent transitions as none already set on View for the condition.
 541                 ILayoutParent layoutParent = layoutPositionData.Item.GetParent();
 542                 if (layoutParent !=null)
 543                 {
 544                     // Item doesn't have it's own transitions for this condition so copy parents if
 545                     // has a parent with transitions.
 546                     LayoutGroup layoutGroup = layoutParent as LayoutGroup;
 547                     TransitionList parentTransitionList;
 548                     // Note TryGetValue returns null if key not matched.
 549                     if (layoutGroup !=null && layoutGroup.Owner.LayoutTransitions.TryGetValue(conditionForAnimators, out parentTransitionList))
 550                     {
 551                         // Copy parent transitions to temporary TransitionList. List contains transitions for the current condition.
 552                         LayoutTransitionsHelper.CopyTransitions(parentTransitionList,
 553                                                                 transitionsForCurrentCondition);
 554                     }
 555                 }
 556             }
 557
 558
 559             // Position/Size transitions can be displayed for a layout changing to another layout or an item being added or removed.
 560
 561             // There can only be one position transition and one size position, they will be replaced if set multiple times.
 562             // transitionsForCurrentCondition represent all non position (custom) properties that should be animated.
 563
 564             // Search for Position property in the transitionsForCurrentCondition list of custom transitions,
 565             // and only use the particular parts of the animator as custom transitions should not effect all parameters of Position.
 566             // Typically Delay, Duration and Alphafunction can be custom.
 567             FindAndReplaceAnimatorComponentsForProperty(transitionsForCurrentCondition,
 568                                                         AnimatableProperties.Position,
 569                                                         ref positionTransitionComponents);
 570
 571             // Size
 572             FindAndReplaceAnimatorComponentsForProperty(transitionsForCurrentCondition,
 573                                                         AnimatableProperties.Size,
 574                                                         ref sizeTransitionComponents);
 575
 576             // Add animators to the core Animation,
 577
 578             SetupAnimationForCustomTransitions(transitionsForCurrentCondition, layoutPositionData.Item.Owner);
 579
 580             SetupAnimationForPosition(layoutPositionData, positionTransitionComponents);
 581
 582             SetupAnimationForSize(layoutPositionData, sizeTransitionComponents);
 583         }
 584
 585     } // class LayoutController
 586 } // namespace Tizen.NUI