1 #ifndef DALI_TOOLKIT_LAYOUTING_LAYOUT_GROUP_H
2 #define DALI_TOOLKIT_LAYOUTING_LAYOUT_GROUP_H
4 * Copyright (c) 2018 Samsung Electronics Co., Ltd.
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
10 * http://www.apache.org/licenses/LICENSE-2.0
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
20 #include <dali/public-api/common/dali-common.h>
21 #include <dali/public-api/actors/actor-enumerations.h>
22 #include <dali-toolkit/devel-api/toolkit-property-index-ranges.h>
23 #include <dali-toolkit/devel-api/layouting/layout-item.h>
24 #include <dali-toolkit/devel-api/layouting/measure-spec.h>
25 #include <dali-toolkit/public-api/dali-toolkit-common.h>
39 * A layout that has layout children. Implements LayoutItem.
40 * It can both layout it's children, and be laid out by a parent container.
42 * A layout group automatically handles adding a Control container's children to itself,
43 * both on startup and on child add/remove. If this functionality is not desired, this needs
44 * splitting into two classes; one that manages just the layout part, and the other which
45 * handles Actor hierarchy. (@todo Consider doing this anyway...)
47 * This handle class allows the application to set up layout properties for the layout group;
48 * it doesn't access measure/layout directly.
50 * To write a new layout, inherit from both LayoutGroup handle and Internal::LayoutGroup body.
53 class DALI_TOOLKIT_API LayoutGroup : public LayoutItem
56 using LayoutId = unsigned int;
57 static const unsigned int UNKNOWN_ID = 0;
63 MARGIN_SPECIFICATION = LAYOUT_GROUP_CHILD_PROPERTY_START_INDEX,
69 * @brief Creates an uninitialized LayoutGroup handle.
71 * LayoutGroup is intended as a base class, and as such, does not have a New method.
73 * Calling member functions with an uninitialized handle is not allowed.
78 * @brief Default Destructor.
80 * This is non-virtual since derived Handle types must not contain data or virtual methods.
82 ~LayoutGroup() = default;
85 * @brief Copy constructor
87 LayoutGroup(const LayoutGroup& copy) = default;
90 * @brief Assigment operator
92 LayoutGroup& operator=(const LayoutGroup& rhs) = default;
95 * @brief Downcasts a handle to a LayoutGroup handle.
97 * If handle points to a LayoutGroup, the downcast produces a valid handle.
98 * If not, the returned handle is left uninitialized.
100 * @param[in] handle to an object
101 * @return Handle to a LayoutGroup or an uninitialized handle
103 static LayoutGroup DownCast( BaseHandle handle );
106 * @brief Add a child layout to the layout group
108 * @param[in] childLayout The layout to add.
109 * @return an Id of the child.
111 LayoutId Add( LayoutItem& childLayout );
114 * @brief Add a child layout to the layout group
116 * @param[in] childId the id of the child to remove
118 void Remove( LayoutId childId );
121 * @brief Remove a child layout from the layout group
123 * @param[in] childLayout The layout to remove.
125 void Remove( LayoutItem& childLayout );
128 * @brief Get the child at the given index.
130 * @param[in] index The index of the child.
132 LayoutItem GetChildAt( unsigned int index ) const;
135 * @brief Get the count of the children of the layout
137 * @return the count of the children of the layout
139 unsigned int GetChildCount() const ;
142 * @brief Get the child referenced by childId.
144 * @param[in] childId The id of the child to get
145 * @return A handle to the child layout, or empty if not found
147 LayoutItem GetChild( LayoutId childId ) const ;
150 * Delete template method to remove implicit casting to integer types.
152 template <typename T>
153 LayoutItem GetChild( T childId ) = delete;
158 * @brief This constructor is used by LayoutGroup::New() methods.
160 * @param[in] actor A pointer to a newly allocated Dali resource
162 explicit LayoutGroup( Internal::LayoutGroup* layoutGroup );
167 } // namespace Toolkit
170 #endif // DALI_TOOLKIT_LAYOUTING_LAYOUT_GROUP_H