OpenShot Audio Library | OpenShotAudio  0.3.2
juce_Value.h
1 /*
2  ==============================================================================
3 
4  This file is part of the JUCE library.
5  Copyright (c) 2017 - ROLI Ltd.
6 
7  JUCE is an open source library subject to commercial or open-source
8  licensing.
9 
10  By using JUCE, you agree to the terms of both the JUCE 5 End-User License
11  Agreement and JUCE 5 Privacy Policy (both updated and effective as of the
12  27th April 2017).
13 
14  End User License Agreement: www.juce.com/juce-5-licence
15  Privacy Policy: www.juce.com/juce-5-privacy-policy
16 
17  Or: You may also use this code under the terms of the GPL v3 (see
18  www.gnu.org/licenses).
19 
20  JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
21  EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
22  DISCLAIMED.
23 
24  ==============================================================================
25 */
26 
27 namespace juce
28 {
29 
30 //==============================================================================
51 class JUCE_API Value final
52 {
53 public:
54  //==============================================================================
56  Value();
57 
64  Value (const Value& other);
65 
67  explicit Value (const var& initialValue);
68 
70  Value (Value&&) noexcept;
71 
73  ~Value();
74 
75  //==============================================================================
77  var getValue() const;
78 
80  operator var() const;
81 
85  String toString() const;
86 
94  void setValue (const var& newValue);
95 
103  Value& operator= (const var& newValue);
104 
106  Value& operator= (Value&&) noexcept;
107 
116  void referTo (const Value& valueToReferTo);
117 
120  bool refersToSameSourceAs (const Value& other) const;
121 
126  bool operator== (const Value& other) const;
127 
132  bool operator!= (const Value& other) const;
133 
134  //==============================================================================
138  class JUCE_API Listener
139  {
140  public:
141  Listener() = default;
142  virtual ~Listener() = default;
143 
150  virtual void valueChanged (Value& value) = 0;
151  };
152 
164  void addListener (Listener* listener);
165 
167  void removeListener (Listener* listener);
168 
169 
170  //==============================================================================
178  class JUCE_API ValueSource : public ReferenceCountedObject,
179  private AsyncUpdater
180  {
181  public:
182  ValueSource();
183  ~ValueSource() override;
184 
186  virtual var getValue() const = 0;
187 
191  virtual void setValue (const var& newValue) = 0;
192 
199  void sendChangeMessage (bool dispatchSynchronously);
200 
201  protected:
202  //==============================================================================
203  friend class Value;
204  SortedSet<Value*> valuesWithListeners;
205 
206  private:
207  void handleAsyncUpdate() override;
208 
209  JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (ValueSource)
210  };
211 
212 
213  //==============================================================================
215  explicit Value (ValueSource* valueSource);
216 
218  ValueSource& getValueSource() noexcept { return *value; }
219 
220 
221 private:
222  //==============================================================================
223  friend class ValueSource;
225  ListenerList<Listener> listeners;
226 
227  void callListeners();
228  void removeFromListenerList();
229 
230  // This is disallowed to avoid confusion about whether it should
231  // do a by-value or by-reference copy.
232  Value& operator= (const Value&) = delete;
233 
234  // This declaration prevents accidental construction from an integer of 0,
235  // which is possible in some compilers via an implicit cast to a pointer.
236  explicit Value (void*) = delete;
237 };
238 
240 OutputStream& JUCE_CALLTYPE operator<< (OutputStream&, const Value&);
241 
242 
243 } // namespace juce
virtual void valueChanged(Value &value)=0
virtual var getValue() const =0
virtual void setValue(const var &newValue)=0
ValueSource & getValueSource() noexcept
Definition: juce_Value.h:218