Move confirmation to remove mixer channels outside MixerView::deleteChannel #7154)

Moves the confirmation to remove mixer channels outside of `MixerView::deleteChannel` and into `MixerChannelView::removeChannel`. This is so that the confirmation only applies when the user uses the context menu to remove a channel, which is important since no confirmation should apply when, for example, the mixer view is cleared with calls to `MixerView::clear`.

include/MixerChannelView.h

@@ -104,6 +104,7 @@ namespace lmms::gui
         void moveChannelRight();
 
     private:
+        bool confirmRemoval(int index);
         QString elideName(const QString& name);
         MixerChannel* mixerChannel() const;
         auto isMasterChannel() const -> bool { return m_channelIndex == 0; }

include/MixerView.h

@@ -78,7 +78,6 @@ public:
 
 	// notify the view that a mixer channel was deleted
 	void deleteChannel(int index);
-	bool confirmRemoval(int index);
 
 	// delete all unused channels
 	void deleteUnusedChannels();

src/gui/MixerChannelView.cpp

@@ -29,6 +29,7 @@
 #include "MixerChannelView.h"
 #include "MixerView.h"
 #include "Song.h"
+#include "ConfigManager.h"
 
 #include "gui_templates.h"
 #include "lmms_math.h"
@@ -38,6 +39,8 @@
 #include <QMenu>
 #include <QPainter>
 #include <QFont>
+#include <QMessageBox>
+#include <QCheckBox>
 
 #include <cassert>
 
@@ -412,8 +415,44 @@ namespace lmms::gui
         update();
     }
 
+	bool MixerChannelView::confirmRemoval(int index)
+	{
+		// if config variable is set to false, there is no need for user confirmation
+		bool needConfirm = ConfigManager::inst()->value("ui", "mixerchanneldeletionwarning", "1").toInt();
+		if (!needConfirm) { return true; }
+
+		// is the channel is not in use, there is no need for user confirmation
+		if (!getGUI()->mixerView()->getMixer()->isChannelInUse(index)) { return true; }
+
+		QString messageRemoveTrack = tr("This Mixer Channel is being used.\n"
+										"Are you sure you want to remove this channel?\n\n"
+										"Warning: This operation can not be undone.");
+
+		QString messageTitleRemoveTrack = tr("Confirm removal");
+		QString askAgainText = tr("Don't ask again");
+		auto askAgainCheckBox = new QCheckBox(askAgainText, nullptr);
+		connect(askAgainCheckBox, &QCheckBox::stateChanged, [](int state) {
+			// Invert button state, if it's checked we *shouldn't* ask again
+			ConfigManager::inst()->setValue("ui", "mixerchanneldeletionwarning", state ? "0" : "1");
+		});
+
+		QMessageBox mb(this);
+		mb.setText(messageRemoveTrack);
+		mb.setWindowTitle(messageTitleRemoveTrack);
+		mb.setIcon(QMessageBox::Warning);
+		mb.addButton(QMessageBox::Cancel);
+		mb.addButton(QMessageBox::Ok);
+		mb.setCheckBox(askAgainCheckBox);
+		mb.setDefaultButton(QMessageBox::Cancel);
+
+		int answer = mb.exec();
+
+		return answer == QMessageBox::Ok;
+	}
+
     void MixerChannelView::removeChannel()
     {
+		if (!confirmRemoval(m_channelIndex)) { return; }
         auto mix = getGUI()->mixerView();
         mix->deleteChannel(m_channelIndex);
     }

src/gui/MixerView.cpp

@@ -23,9 +23,7 @@
  */
 
 
-#include <QCheckBox>
 #include <QLayout>
-#include <QMessageBox>
 #include <QPushButton>
 #include <QScrollArea>
 #include <QStyle>
@@ -377,12 +375,6 @@ void MixerView::deleteChannel(int index)
 	// can't delete master
 	if (index == 0) return;
 
-	// if there is no user confirmation, do nothing
-	if (!confirmRemoval(index))
-	{
-		return;
-	}
-
 	// Disconnect from the solo/mute models of the channel we are about to delete
 	disconnectFromSoloAndMute(index);
 
@@ -421,47 +413,6 @@ void MixerView::deleteChannel(int index)
 	updateMaxChannelSelector();
 }
 
-bool MixerView::confirmRemoval(int index)
-{
-	// if config variable is set to false, there is no need for user confirmation
-	bool needConfirm = ConfigManager::inst()->value("ui", "mixerchanneldeletionwarning", "1").toInt();
-	if (!needConfirm) { return true; }
-
-	Mixer* mix = getMixer();
-
-	if (!mix->isChannelInUse(index))
-	{
-		// is the channel is not in use, there is no need for user confirmation
-		return true;
-	}
-
-	QString messageRemoveTrack = tr("This Mixer Channel is being used.\n"
-									"Are you sure you want to remove this channel?\n\n"
-									"Warning: This operation can not be undone.");
-
-	QString messageTitleRemoveTrack = tr("Confirm removal");
-	QString askAgainText = tr("Don't ask again");
-	auto askAgainCheckBox = new QCheckBox(askAgainText, nullptr);
-	connect(askAgainCheckBox, &QCheckBox::stateChanged, [](int state) {
-		// Invert button state, if it's checked we *shouldn't* ask again
-		ConfigManager::inst()->setValue("ui", "mixerchanneldeletionwarning", state ? "0" : "1");
-	});
-
-	QMessageBox mb(this);
-	mb.setText(messageRemoveTrack);
-	mb.setWindowTitle(messageTitleRemoveTrack);
-	mb.setIcon(QMessageBox::Warning);
-	mb.addButton(QMessageBox::Cancel);
-	mb.addButton(QMessageBox::Ok);
-	mb.setCheckBox(askAgainCheckBox);
-	mb.setDefaultButton(QMessageBox::Cancel);
-
-	int answer = mb.exec();
-
-	return answer == QMessageBox::Ok;
-}
-
-
 void MixerView::deleteUnusedChannels()
 {
 	Mixer* mix = getMixer();