2 * Copyright (c) 2018 Samsung Electronics Co., Ltd.
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
8 * http://www.apache.org/licenses/LICENSE-2.0
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.
18 using System.ComponentModel;
19 using Tizen.NUI.BaseComponents;
24 /// [Draft] LayoutGroup class providing container functionality.
26 internal class LayoutGroup : LayoutGroupWrapper
28 public LayoutGroup() : base(new LayoutGroupWrapperImpl())
30 // Initialize delegates of LayoutItem
31 LayoutItemInitialize(layoutGroupWrapperImpl);
33 layoutGroupWrapperImpl.OnMeasure = new LayoutGroupWrapperImpl.OnMeasureDelegate(OnMeasure);
34 layoutGroupWrapperImpl.OnLayout = new LayoutGroupWrapperImpl.OnLayoutDelegate(OnLayout);
35 layoutGroupWrapperImpl.OnSizeChanged = new LayoutGroupWrapperImpl.OnSizeChangedDelegate(OnSizeChanged);
36 layoutGroupWrapperImpl.OnChildAdd = new LayoutGroupWrapperImpl.OnChildAddDelegate(OnChildAdd);
37 layoutGroupWrapperImpl.OnChildRemove = new LayoutGroupWrapperImpl.OnChildRemoveDelegate(OnChildRemove);
38 layoutGroupWrapperImpl.DoInitialize = new LayoutGroupWrapperImpl.DoInitializeDelegate(DoInitialize);
39 layoutGroupWrapperImpl.DoRegisterChildProperties = new LayoutGroupWrapperImpl.DoRegisterChildPropertiesDelegate(DoRegisterChildProperties);
40 layoutGroupWrapperImpl.MeasureChildren = new LayoutGroupWrapperImpl.MeasureChildrenDelegate(MeasureChildren);
41 layoutGroupWrapperImpl.MeasureChild = new LayoutGroupWrapperImpl.MeasureChildDelegate(MeasureChild);
42 layoutGroupWrapperImpl.MeasureChildWithMargins = new LayoutGroupWrapperImpl.MeasureChildWithMarginsDelegate(MeasureChildWithMargins);
46 /// Remove all layout children.<br />
48 public void RemoveAll()
50 layoutGroupWrapperImpl.RemoveAll();
54 /// Get the child layout id of the given child.<br />
56 /// <param name="child">The given Layout child.</param>
57 internal uint GetChildId(LayoutItemWrapperImpl child)
59 return layoutGroupWrapperImpl.GetChildId(child);
63 /// Calculate the right measure spec for this child.
64 /// Does the hard part of MeasureChildren: figuring out the MeasureSpec to
65 /// pass to a particular child. This method figures out the right MeasureSpec
66 /// for one dimension (height or width) of one child view.<br />
68 /// <param name="measureSpec">The requirements for this view.</param>
69 /// <param name="padding">The padding of this view for the current dimension and margins, if applicable.</param>
70 /// <param name="childDimension"> How big the child wants to be in the current dimension.</param>
71 /// <returns>a MeasureSpec for the child.</returns>
72 public static LayoutMeasureSpec GetChildMeasureSpec(LayoutMeasureSpec measureSpec, LayoutLength padding, LayoutLength childDimension)
74 return LayoutGroupWrapperImpl.GetChildMeasureSpec(measureSpec, padding, childDimension);
78 /// Measure the layout and its content to determine the measured width and the measured height.<br />
79 /// If this method is overridden, it is the subclass's responsibility to make
80 /// sure the measured height and width are at least the layout's minimum height
83 /// <param name="widthMeasureSpec">horizontal space requirements as imposed by the parent.</param>
84 /// <param name="heightMeasureSpec">vertical space requirements as imposed by the parent.</param>
85 protected virtual void OnMeasure(LayoutMeasureSpec widthMeasureSpec, LayoutMeasureSpec heightMeasureSpec)
87 LayoutLength childWidth = new LayoutLength( 0 );
88 LayoutLength childHeight = new LayoutLength( 0 );
90 LayoutLength measuredWidth = childWidth;
91 LayoutLength measuredHeight = childHeight;
93 for( uint i = 0; i < ChildCount; ++i )
95 var childLayout = GetChildAt( i );
98 MeasureChild( childLayout, widthMeasureSpec, heightMeasureSpec );
99 childWidth = childLayout.MeasuredWidth;
100 childHeight = childLayout.MeasuredHeight;
101 // Layout takes size of largest width and height dimension of children
102 measuredWidth.Value = System.Math.Max( measuredWidth.Value, childWidth.Value );
103 measuredHeight.Value = System.Math.Max( measuredHeight.Value, childHeight.Value );
107 if( 0 == ChildCount )
109 // Must be a leaf as has no children
110 measuredWidth = GetDefaultSize( SuggestedMinimumWidth, widthMeasureSpec );
111 measuredHeight = GetDefaultSize( SuggestedMinimumHeight, heightMeasureSpec );
114 SetMeasuredDimensions( new MeasuredSize( measuredWidth ),
115 new MeasuredSize( measuredHeight ) );
119 /// Called from Layout() when this layout should assign a size and position to each of its children.<br />
120 /// Derived classes with children should override this method and call Layout() on each of their children.<br />
122 /// <param name="changed">This is a new size or position for this layout.</param>
123 /// <param name="left">Left position, relative to parent.</param>
124 /// <param name="top"> Top position, relative to parent.</param>
125 /// <param name="right">Right position, relative to parent.</param>
126 /// <param name="bottom">Bottom position, relative to parent.</param>
127 protected virtual void OnLayout(bool changed, LayoutLength left, LayoutLength top, LayoutLength right, LayoutLength bottom)
133 /// Virtual method to inform derived classes when the layout size changed.<br />
135 /// <param name="newSize">The new size of the layout.</param>
136 /// <param name="oldSize">The old size of the layout.</param>
137 protected virtual void OnSizeChanged(LayoutSize newSize, LayoutSize oldSize)
143 /// Callback when child is added to container.<br />
144 /// Derived classes can use this to set their own child properties on the child layout's owner.<br />
146 /// <param name="child">The Layout child.</param>
147 internal virtual void OnChildAdd(LayoutItemWrapperImpl child)
152 /// Callback when child is removed from container.<br />
154 /// <param name="child">The Layout child.</param>
155 internal virtual void OnChildRemove(LayoutItemWrapperImpl child)
160 /// Second stage initialization method for deriving classes to override.<br />
162 protected virtual void DoInitialize()
167 /// Method for derived classes to implement in order to register child property types with the container.<br />
169 /// <param name="containerType">The fully qualified typename of the container.</param>
170 protected virtual void DoRegisterChildProperties(string containerType)
175 /// Ask all of the children of this view to measure themselves, taking into
176 /// account both the MeasureSpec requirements for this view and its padding.<br />
177 /// The heavy lifting is done in GetChildMeasureSpec.<br />
179 /// <param name="widthMeasureSpec">The width requirements for this view.</param>
180 /// <param name="heightMeasureSpec">The height requirements for this view.</param>
181 protected virtual void MeasureChildren(LayoutMeasureSpec widthMeasureSpec, LayoutMeasureSpec heightMeasureSpec)
183 layoutGroupWrapperImpl.MeasureChildrenNative(widthMeasureSpec, heightMeasureSpec);
187 /// Ask one of the children of this view to measure itself, taking into
188 /// account both the MeasureSpec requirements for this view and its padding.<br />
189 /// The heavy lifting is done in GetChildMeasureSpec.<br />
191 /// <param name="child">The child to measure.</param>
192 /// <param name="parentWidthMeasureSpec">The width requirements for this view.</param>
193 /// <param name="parentHeightMeasureSpec">The height requirements for this view.</param>
194 protected virtual void MeasureChild(LayoutItem child, LayoutMeasureSpec parentWidthMeasureSpec, LayoutMeasureSpec parentHeightMeasureSpec)
196 layoutGroupWrapperImpl.MeasureChildNative(child, parentWidthMeasureSpec, parentHeightMeasureSpec);
200 /// Ask one of the children of this view to measure itself, taking into
201 /// account both the MeasureSpec requirements for this view and its padding.<br />
202 /// and margins. The child must have MarginLayoutParams The heavy lifting is
203 /// done in GetChildMeasureSpec.<br />
205 /// <param name="child">The child to measure.</param>
206 /// <param name="parentWidthMeasureSpec">The width requirements for this view.</param>
207 /// <param name="widthUsed">Extra space that has been used up by the parent horizontally (possibly by other children of the parent).</param>
208 /// <param name="parentHeightMeasureSpec">The height requirements for this view.</param>
209 /// <param name="heightUsed">Extra space that has been used up by the parent vertically (possibly by other children of the parent).</param>
210 protected virtual void MeasureChildWithMargins(LayoutItem child, LayoutMeasureSpec parentWidthMeasureSpec, LayoutLength widthUsed, LayoutMeasureSpec parentHeightMeasureSpec, LayoutLength heightUsed)
212 layoutGroupWrapperImpl.MeasureChildWithMarginsNative(child, parentWidthMeasureSpec, widthUsed, parentHeightMeasureSpec, heightUsed);