9 files changed, 22 insertions, 1 deletions
diff --git a/demos/spectrum/app/engine.h b/demos/spectrum/app/engine.h
index 16088b2..93733fe 100644
--- a/demos/spectrum/app/engine.h
+++ b/demos/spectrum/app/engine.h
@@ -61,10 +61,13 @@
 #include <QDir>
 #endif
 
+QT_BEGIN_NAMESPACE
 class QAudioInput;
 class QAudioOutput;
-class FrequencySpectrum;
 class QFile;
+QT_END_NAMESPACE
+
+class FrequencySpectrum;
 
 /**
  * This class interfaces with the QtMultimedia audio classes, and also with
diff --git a/demos/spectrum/app/mainwidget.h b/demos/spectrum/app/mainwidget.h
index 846b97a..c59dbd6 100644
--- a/demos/spectrum/app/mainwidget.h
+++ b/demos/spectrum/app/mainwidget.h
@@ -50,11 +50,14 @@ class Waveform;
 class LevelMeter;
 class SettingsDialog;
 class ToneGeneratorDialog;
+
+QT_BEGIN_NAMESPACE
 class QAudioFormat;
 class QLabel;
 class QPushButton;
 class QMenu;
 class QAction;
+QT_END_NAMESPACE
 
 /**
  * Main application widget, responsible for connecting the various UI
diff --git a/demos/spectrum/app/settingsdialog.h b/demos/spectrum/app/settingsdialog.h
index 7215a50..fda518b 100644
--- a/demos/spectrum/app/settingsdialog.h
+++ b/demos/spectrum/app/settingsdialog.h
@@ -42,11 +42,13 @@
 #include <QDialog>
 #include <QtMultimedia/QAudioDeviceInfo>
 
+QT_BEGIN_NAMESPACE
 class QComboBox;
 class QCheckBox;
 class QSlider;
 class QSpinBox;
 class QGridLayout;
+QT_END_NAMESPACE
 
 /**
  * Dialog used to control settings such as the audio input / output device
diff --git a/demos/spectrum/app/spectrograph.h b/demos/spectrum/app/spectrograph.h
index 6bfef33..a7790ff 100644
--- a/demos/spectrum/app/spectrograph.h
+++ b/demos/spectrum/app/spectrograph.h
@@ -41,7 +41,9 @@
 #include <QWidget>
 #include "frequencyspectrum.h"
 
+QT_BEGIN_NAMESPACE
 class QMouseEvent;
+QT_END_NAMESPACE
 
 /**
  * Widget which displays a spectrograph showing the frequency spectrum
diff --git a/demos/spectrum/app/spectrumanalyser.h b/demos/spectrum/app/spectrumanalyser.h
index caeb1c1..f10da63 100644
--- a/demos/spectrum/app/spectrumanalyser.h
+++ b/demos/spectrum/app/spectrumanalyser.h
@@ -55,8 +55,11 @@
 #include "FFTRealFixLenParam.h"
 #endif
 
+QT_BEGIN_NAMESPACE
 class QAudioFormat;
 class QThread;
+QT_END_NAMESPACE
+
 class FFTRealWrapper;
 
 class SpectrumAnalyserThreadPrivate;
diff --git a/demos/spectrum/app/tonegenerator.h b/demos/spectrum/app/tonegenerator.h
index 419f7e4..d387768 100644
--- a/demos/spectrum/app/tonegenerator.h
+++ b/demos/spectrum/app/tonegenerator.h
@@ -41,8 +41,10 @@
 #include <QtCore/qglobal.h>
 #include "spectrum.h"
 
+QT_BEGIN_NAMESPACE
 class QAudioFormat;
 class QByteArray;
+QT_END_NAMESPACE
 
 /**
  * Generate a sine wave
diff --git a/demos/spectrum/app/tonegeneratordialog.h b/demos/spectrum/app/tonegeneratordialog.h
index 35d69c2..d6fcffa 100644
--- a/demos/spectrum/app/tonegeneratordialog.h
+++ b/demos/spectrum/app/tonegeneratordialog.h
@@ -42,10 +42,12 @@
 #include <QDialog>
 #include <QtMultimedia/QAudioDeviceInfo>
 
+QT_BEGIN_NAMESPACE
 class QCheckBox;
 class QSlider;
 class QSpinBox;
 class QGridLayout;
+QT_END_NAMESPACE
 
 /**
  * Dialog which controls the parameters of the tone generator.
diff --git a/demos/spectrum/app/utils.h b/demos/spectrum/app/utils.h
index 83467cd..548f884 100644
--- a/demos/spectrum/app/utils.h
+++ b/demos/spectrum/app/utils.h
@@ -41,7 +41,9 @@
 #include <QtCore/qglobal.h>
 #include <QDebug>
 
+QT_BEGIN_NAMESPACE
 class QAudioFormat;
+QT_END_NAMESPACE
 
 //-----------------------------------------------------------------------------
 // Miscellaneous utility functions
diff --git a/demos/spectrum/app/waveform.h b/demos/spectrum/app/waveform.h
index 4de527f..909e5ee 100644
--- a/demos/spectrum/app/waveform.h
+++ b/demos/spectrum/app/waveform.h
@@ -43,7 +43,9 @@
 #include <QPixmap>
 #include <QScopedPointer>
 
+QT_BEGIN_NAMESPACE
 class QByteArray;
+QT_END_NAMESPACE
 
 /**
  * Widget which displays a section of the audio waveform.