Added QML API for getting the limits for a specific radio band.

Using properties for the frequency step, minimum and maximum
frequency of the currently selected band.
Also updated the declarative-radio example to use the minimum
and maximum frequencies to show a tuner band for the radio.

Change-Id: I9f28f10e98e008c14b10bdc12b0727086cd45f0b
Reviewed-on: http://codereview.qt.nokia.com/3829
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: Dmytro Poplavskiy <dmytro.poplavskiy@nokia.com>

examples/declarative-radio/view.qml

@@ -46,11 +46,13 @@ Rectangle {
 
     Radio {
         id: radio
+        band: Radio.FM
     }
 
     Column {
         anchors.fill: parent
         anchors.margins: 5
+        spacing: 5
 
         Row {
 
@@ -61,7 +63,7 @@ Rectangle {
                 height: 200
 
                 verticalAlignment: Text.AlignVCenter
-                text: "" + radio.frequency / 1000 + " kHz";
+                text: "" + radio.frequency / 1000 + " kHz"
             }
             Text {
                 id: sig
@@ -74,6 +76,28 @@ Rectangle {
             }
         }
 
+        Row {
+            spacing: 5
+
+            Rectangle {
+                width: 350
+                height: 10
+
+                color: "black"
+
+                Rectangle {
+                    width: 5
+                    height: 10
+                    color: "red"
+
+                    y: 0
+                    x: (parent.width - 5) * ((radio.frequency - radio.minimumFrequency) / (radio.maximumFrequency -
+                    radio.minimumFrequency))
+
+                }
+            }
+        }
+
 
         Row {
             spacing: 5
@@ -119,7 +143,7 @@ Rectangle {
                     anchors.fill: parent
                     onClicked:  {
                         var f = radio.frequency;
-                        f = f - radio.frequencyStep(Radio.FM);
+                        f = f - radio.frequencyStep;
                         radio.setFrequency(f);
                     }
                 }
@@ -144,7 +168,7 @@ Rectangle {
                     anchors.fill: parent
                     onClicked:  {
                         var f = radio.frequency;
-                        f = f + radio.frequencyStep(Radio.FM);
+                        f = f + radio.frequencyStep;
                         radio.setFrequency(f);
                     }
                 }

src/imports/multimedia/qdeclarativeradio.cpp

@@ -111,16 +111,26 @@ bool QDeclarativeRadio::searching() const
     return m_radioTuner->isSearching();
 }
 
+int QDeclarativeRadio::frequencyStep() const
+{
+    return m_radioTuner->frequencyStep(m_radioTuner->band());
+}
+
+int QDeclarativeRadio::minimumFrequency() const
+{
+    return m_radioTuner->frequencyRange(m_radioTuner->band()).first;
+}
+
+int QDeclarativeRadio::maximumFrequency() const
+{
+    return m_radioTuner->frequencyRange(m_radioTuner->band()).second;
+}
+
 bool QDeclarativeRadio::isAvailable() const
 {
     return m_radioTuner->isAvailable();
 }
 
-int QDeclarativeRadio::frequencyStep(QDeclarativeRadio::Band band) const
-{
-    return m_radioTuner->frequencyStep(static_cast<QRadioTuner::Band>(band));
-}
-
 void QDeclarativeRadio::setBand(QDeclarativeRadio::Band band)
 {
     m_radioTuner->setBand(static_cast<QRadioTuner::Band>(band));

src/imports/multimedia/qdeclarativeradio_p.h

@@ -72,6 +72,9 @@ class QDeclarativeRadio : public QObject
     Q_PROPERTY(int volume READ volume WRITE setVolume NOTIFY volumeChanged)
     Q_PROPERTY(bool muted READ muted WRITE setMuted NOTIFY mutedChanged)
     Q_PROPERTY(bool searching READ searching NOTIFY searchingChanged)
+    Q_PROPERTY(int frequencyStep READ frequencyStep NOTIFY bandChanged)
+    Q_PROPERTY(int minimumFrequency READ minimumFrequency NOTIFY bandChanged)
+    Q_PROPERTY(int maximumFrequency READ maximumFrequency NOTIFY bandChanged)
     Q_ENUMS(State)
     Q_ENUMS(Band)
     Q_ENUMS(Error)
@@ -118,8 +121,11 @@ public:
     int signalStrength() const;
     bool searching() const;
 
+    int frequencyStep() const;
+    int minimumFrequency() const;
+    int maximumFrequency() const;
+
     Q_INVOKABLE bool isAvailable() const;
-    Q_INVOKABLE int frequencyStep(QDeclarativeRadio::Band band) const;
 
 public Q_SLOTS:
     void setBand(QDeclarativeRadio::Band band);