git.sesse.net Git - nageru/blob - midi_mapping_dialog.cpp

   1 #include "midi_mapping_dialog.h"
   2
   3 #include "midi_mapper.h"
   4 #include "midi_mapping.pb.h"
   5 #include "post_to_main_thread.h"
   6 #include "ui_midi_mapping.h"
   7
   8 #include <QComboBox>
   9 #include <QFileDialog>
  10 #include <QMessageBox>
  11 #include <QSpinBox>
  12
  13 #include <algorithm>
  14 #include <string>
  15
  16 using namespace google::protobuf;
  17 using namespace std;
  18
  19 vector<MIDIMappingDialog::Control> per_bus_controllers = {
  20         { "Treble",                   MIDIMappingBusProto::kTrebleFieldNumber, MIDIMappingProto::kTrebleBankFieldNumber },
  21         { "Mid",                      MIDIMappingBusProto::kMidFieldNumber,    MIDIMappingProto::kMidBankFieldNumber },
  22         { "Bass",                     MIDIMappingBusProto::kBassFieldNumber,   MIDIMappingProto::kBassBankFieldNumber },
  23         { "Gain",                     MIDIMappingBusProto::kGainFieldNumber,   MIDIMappingProto::kGainBankFieldNumber },
  24         { "Compressor threshold",     MIDIMappingBusProto::kCompressorThresholdFieldNumber,
  25                                       MIDIMappingProto::kCompressorThresholdBankFieldNumber},
  26         { "Fader",                    MIDIMappingBusProto::kFaderFieldNumber,  MIDIMappingProto::kFaderBankFieldNumber }
  27 };
  28 vector<MIDIMappingDialog::Control> per_bus_buttons = {
  29         { "Toggle locut",             MIDIMappingBusProto::kToggleLocutFieldNumber,
  30                                       MIDIMappingProto::kToggleLocutBankFieldNumber },
  31         { "Togle auto gain staging",  MIDIMappingBusProto::kToggleAutoGainStagingFieldNumber,
  32                                       MIDIMappingProto::kToggleAutoGainStagingBankFieldNumber },
  33         { "Togle compressor",         MIDIMappingBusProto::kToggleCompressorFieldNumber,
  34                                       MIDIMappingProto::kToggleCompressorBankFieldNumber },
  35         { "Clear peak",               MIDIMappingBusProto::kClearPeakFieldNumber,
  36                                       MIDIMappingProto::kClearPeakBankFieldNumber }
  37 };
  38 vector<MIDIMappingDialog::Control> global_controllers = {
  39         { "Locut cutoff",             MIDIMappingBusProto::kLocutFieldNumber,  MIDIMappingProto::kLocutBankFieldNumber },
  40         { "Limiter threshold",        MIDIMappingBusProto::kLimiterThresholdFieldNumber,
  41                                       MIDIMappingProto::kLimiterThresholdBankFieldNumber },
  42         { "Makeup gain",              MIDIMappingBusProto::kMakeupGainFieldNumber,
  43                                       MIDIMappingProto::kMakeupGainBankFieldNumber }
  44 };
  45 vector<MIDIMappingDialog::Control> global_buttons = {
  46         { "Previous bank",            MIDIMappingBusProto::kPrevBankFieldNumber, 0 },
  47         { "Next bank",                MIDIMappingBusProto::kNextBankFieldNumber, 0 },
  48         { "Select bank 1",            MIDIMappingBusProto::kSelectBank1FieldNumber, 0 },
  49         { "Select bank 2",            MIDIMappingBusProto::kSelectBank2FieldNumber, 0 },
  50         { "Select bank 3",            MIDIMappingBusProto::kSelectBank3FieldNumber, 0 },
  51         { "Select bank 4",            MIDIMappingBusProto::kSelectBank4FieldNumber, 0 },
  52         { "Select bank 5",            MIDIMappingBusProto::kSelectBank5FieldNumber, 0 }
  53 };
  54
  55 namespace {
  56
  57 int get_bank(const MIDIMappingProto &mapping_proto, int bank_field_number, int default_value)
  58 {
  59         const FieldDescriptor *bank_descriptor = mapping_proto.GetDescriptor()->FindFieldByNumber(bank_field_number);
  60         const Reflection *reflection = mapping_proto.GetReflection();
  61         if (!reflection->HasField(mapping_proto, bank_descriptor)) {
  62                 return default_value;
  63         }
  64         return reflection->GetInt32(mapping_proto, bank_descriptor);
  65 }
  66
  67 int get_controller_mapping(const MIDIMappingProto &mapping_proto, size_t bus_idx, int field_number, int default_value)
  68 {
  69         if (bus_idx >= size_t(mapping_proto.bus_mapping_size())) {
  70                 return default_value;
  71         }
  72
  73         const MIDIMappingBusProto &bus_mapping = mapping_proto.bus_mapping(bus_idx);
  74         const FieldDescriptor *descriptor = bus_mapping.GetDescriptor()->FindFieldByNumber(field_number);
  75         const Reflection *bus_reflection = bus_mapping.GetReflection();
  76         if (!bus_reflection->HasField(bus_mapping, descriptor)) {
  77                 return default_value;
  78         }
  79         const MIDIControllerProto &controller_proto =
  80                 static_cast<const MIDIControllerProto &>(bus_reflection->GetMessage(bus_mapping, descriptor));
  81         return controller_proto.controller_number();
  82 }
  83
  84 int get_button_mapping(const MIDIMappingProto &mapping_proto, size_t bus_idx, int field_number, int default_value)
  85 {
  86         if (bus_idx >= size_t(mapping_proto.bus_mapping_size())) {
  87                 return default_value;
  88         }
  89
  90         const MIDIMappingBusProto &bus_mapping = mapping_proto.bus_mapping(bus_idx);
  91         const FieldDescriptor *descriptor = bus_mapping.GetDescriptor()->FindFieldByNumber(field_number);
  92         const Reflection *bus_reflection = bus_mapping.GetReflection();
  93         if (!bus_reflection->HasField(bus_mapping, descriptor)) {
  94                 return default_value;
  95         }
  96         const MIDIButtonProto &bus_proto =
  97                 static_cast<const MIDIButtonProto &>(bus_reflection->GetMessage(bus_mapping, descriptor));
  98         return bus_proto.note_number();
  99 }
 100
 101 }  // namespace
 102
 103 MIDIMappingDialog::MIDIMappingDialog(MIDIMapper *mapper)
 104         : ui(new Ui::MIDIMappingDialog),
 105           mapper(mapper)
 106 {
 107         ui->setupUi(this);
 108
 109         const MIDIMappingProto mapping_proto = mapper->get_current_mapping();  // Take a copy.
 110         old_receiver = mapper->set_receiver(this);
 111
 112         QStringList labels;
 113         labels << "";
 114         labels << "Controller bank";
 115         for (unsigned bus_idx = 0; bus_idx < num_buses; ++bus_idx) {
 116                 char buf[256];
 117                 snprintf(buf, sizeof(buf), "Bus %d", bus_idx + 1);
 118                 labels << buf;
 119         }
 120         labels << "";
 121         ui->treeWidget->setColumnCount(num_buses + 3);
 122         ui->treeWidget->setHeaderLabels(labels);
 123
 124         add_controls("Per-bus controllers", ControlType::CONTROLLER, SpinnerGroup::PER_BUS_CONTROLLERS, mapping_proto, per_bus_controllers);
 125         add_controls("Per-bus buttons", ControlType::BUTTON, SpinnerGroup::PER_BUS_BUTTONS, mapping_proto, per_bus_buttons);
 126         add_controls("Global controllers", ControlType::CONTROLLER, SpinnerGroup::GLOBAL_CONTROLLERS, mapping_proto, global_controllers);
 127         add_controls("Global buttons", ControlType::BUTTON, SpinnerGroup::GLOBAL_BUTTONS, mapping_proto, global_buttons);
 128         fill_controls_from_mapping(mapping_proto);
 129
 130         // Auto-resize every column but the last.
 131         for (unsigned column_idx = 0; column_idx < num_buses + 3; ++column_idx) {
 132                 ui->treeWidget->resizeColumnToContents(column_idx);
 133         }
 134
 135         connect(ui->guess_bus_button, &QPushButton::clicked,
 136                 bind(&MIDIMappingDialog::guess_clicked, this, false));
 137         connect(ui->guess_group_button, &QPushButton::clicked,
 138                 bind(&MIDIMappingDialog::guess_clicked, this, true));
 139         connect(ui->ok_cancel_buttons, &QDialogButtonBox::accepted, this, &MIDIMappingDialog::ok_clicked);
 140         connect(ui->ok_cancel_buttons, &QDialogButtonBox::rejected, this, &MIDIMappingDialog::cancel_clicked);
 141         connect(ui->save_button, &QPushButton::clicked, this, &MIDIMappingDialog::save_clicked);
 142         connect(ui->load_button, &QPushButton::clicked, this, &MIDIMappingDialog::load_clicked);
 143
 144         update_guess_button_state();
 145 }
 146
 147 MIDIMappingDialog::~MIDIMappingDialog()
 148 {
 149         mapper->set_receiver(old_receiver);
 150 }
 151
 152 bool MIDIMappingDialog::eventFilter(QObject *obj, QEvent *event)
 153 {
 154         if (event->type() == QEvent::FocusIn ||
 155             event->type() == QEvent::FocusOut) {
 156                 // We ignore the guess buttons themselves; it should be allowed
 157                 // to navigate from a spinner to focus on a button (to click it).
 158                 if (obj != ui->guess_bus_button && obj != ui->guess_group_button) {
 159                         update_guess_button_state();
 160                 }
 161         }
 162         return false;
 163 }
 164
 165 void MIDIMappingDialog::guess_clicked(bool limit_to_group)
 166 {
 167         FocusInfo focus = find_focus();
 168         if (focus.bus_idx == -1) {
 169                 // The guess button probably took the focus away from us.
 170                 focus = last_focus;
 171         }
 172         assert(focus.bus_idx != -1);  // The button should have been disabled.
 173         pair<int, int> bus_and_offset = guess_offset(focus.bus_idx, limit_to_group ? focus.spinner_group : SpinnerGroup::ALL_GROUPS);
 174         const int source_bus_idx = bus_and_offset.first;
 175         const int offset = bus_and_offset.second;
 176         assert(source_bus_idx != -1);  // The button should have been disabled.
 177
 178         for (const auto &field_number_and_spinner : spinners[focus.bus_idx]) {
 179                 int field_number = field_number_and_spinner.first;
 180                 QSpinBox *spinner = field_number_and_spinner.second.spinner;
 181                 SpinnerGroup this_spinner_group = field_number_and_spinner.second.group;
 182
 183                 if (limit_to_group && this_spinner_group != focus.spinner_group) {
 184                         continue;
 185                 }
 186
 187                 assert(spinners[source_bus_idx].count(field_number));
 188                 QSpinBox *source_spinner = spinners[source_bus_idx][field_number].spinner;
 189                 assert(spinners[source_bus_idx][field_number].group == this_spinner_group);
 190
 191                 if (source_spinner->value() != 0) {
 192                         spinner->setValue(source_spinner->value() + offset);
 193                 }
 194         }
 195
 196         // See if we can find a “next” bus to move the focus to.
 197         const int next_bus_idx = focus.bus_idx + (focus.bus_idx - source_bus_idx);  // Note: Could become e.g. -1.
 198         for (const InstantiatedSpinner &is : controller_spinners) {
 199                 if (int(is.bus_idx) == next_bus_idx && is.field_number == focus.field_number) {
 200                         is.spinner->setFocus();
 201                 }
 202         }
 203         for (const InstantiatedSpinner &is : button_spinners) {
 204                 if (int(is.bus_idx) == next_bus_idx && is.field_number == focus.field_number) {
 205                         is.spinner->setFocus();
 206                 }
 207         }
 208 }
 209
 210 void MIDIMappingDialog::ok_clicked()
 211 {
 212         unique_ptr<MIDIMappingProto> new_mapping = construct_mapping_proto_from_ui();
 213         mapper->set_midi_mapping(*new_mapping);
 214         mapper->set_receiver(old_receiver);
 215         accept();
 216 }
 217
 218 void MIDIMappingDialog::cancel_clicked()
 219 {
 220         mapper->set_receiver(old_receiver);
 221         reject();
 222 }
 223
 224 void MIDIMappingDialog::save_clicked()
 225 {
 226         unique_ptr<MIDIMappingProto> new_mapping = construct_mapping_proto_from_ui();
 227         QString filename = QFileDialog::getSaveFileName(this,
 228                 "Save MIDI mapping", QString(), tr("Mapping files (*.midimapping)"));
 229         if (!filename.endsWith(".midimapping")) {
 230                 filename += ".midimapping";
 231         }
 232         if (!save_midi_mapping_to_file(*new_mapping, filename.toStdString())) {
 233                 QMessageBox box;
 234                 box.setText("Could not save mapping to '" + filename + "'. Check that you have the right permissions and try again.");
 235                 box.exec();
 236         }
 237 }
 238
 239 void MIDIMappingDialog::load_clicked()
 240 {
 241         QString filename = QFileDialog::getOpenFileName(this,
 242                 "Load MIDI mapping", QString(), tr("Mapping files (*.midimapping)"));
 243         MIDIMappingProto new_mapping;
 244         if (!load_midi_mapping_from_file(filename.toStdString(), &new_mapping)) {
 245                 QMessageBox box;
 246                 box.setText("Could not load mapping from '" + filename + "'. Check that the file exists, has the right permissions and is valid.");
 247                 box.exec();
 248                 return;
 249         }
 250
 251         fill_controls_from_mapping(new_mapping);
 252 }
 253
 254 namespace {
 255
 256 template<class T>
 257 T *get_mutable_bus_message(MIDIMappingProto *mapping_proto, unsigned bus_idx, int field_number)
 258 {
 259         while (size_t(mapping_proto->bus_mapping_size()) <= bus_idx) {
 260                 mapping_proto->add_bus_mapping();
 261         }
 262
 263         MIDIMappingBusProto *bus_mapping = mapping_proto->mutable_bus_mapping(bus_idx);
 264         const FieldDescriptor *descriptor = bus_mapping->GetDescriptor()->FindFieldByNumber(field_number);
 265         const Reflection *bus_reflection = bus_mapping->GetReflection();
 266         return static_cast<T *>(bus_reflection->MutableMessage(bus_mapping, descriptor));
 267 }
 268
 269 }  // namespace
 270
 271 unique_ptr<MIDIMappingProto> MIDIMappingDialog::construct_mapping_proto_from_ui()
 272 {
 273         unique_ptr<MIDIMappingProto> mapping_proto(new MIDIMappingProto);
 274         for (const InstantiatedSpinner &is : controller_spinners) {
 275                 const int val = is.spinner->value();
 276                 if (val == 0) {
 277                         continue;
 278                 }
 279
 280                 MIDIControllerProto *controller_proto =
 281                         get_mutable_bus_message<MIDIControllerProto>(mapping_proto.get(), is.bus_idx, is.field_number);
 282                 controller_proto->set_controller_number(val);
 283         }
 284         for (const InstantiatedSpinner &is : button_spinners) {
 285                 const int val = is.spinner->value();
 286                 if (val == 0) {
 287                         continue;
 288                 }
 289
 290                 MIDIButtonProto *button_proto =
 291                         get_mutable_bus_message<MIDIButtonProto>(mapping_proto.get(), is.bus_idx, is.field_number);
 292                 button_proto->set_note_number(val);
 293         }
 294         int highest_bank_used = 0;  // 1-indexed.
 295         for (const InstantiatedComboBox &ic : bank_combo_boxes) {
 296                 const int val = ic.combo_box->currentIndex();
 297                 highest_bank_used = std::max(highest_bank_used, val);
 298                 if (val == 0) {
 299                         continue;
 300                 }
 301
 302                 const FieldDescriptor *descriptor = mapping_proto->GetDescriptor()->FindFieldByNumber(ic.field_number);
 303                 const Reflection *bus_reflection = mapping_proto->GetReflection();
 304                 bus_reflection->SetInt32(mapping_proto.get(), descriptor, val - 1);
 305         }
 306         mapping_proto->set_num_controller_banks(highest_bank_used);
 307         return mapping_proto;
 308 }
 309
 310 void MIDIMappingDialog::add_bank_selector(QTreeWidgetItem *item, const MIDIMappingProto &mapping_proto, int bank_field_number)
 311 {
 312         if (bank_field_number == 0) {
 313                 return;
 314         }
 315         QComboBox *bank_selector = new QComboBox(this);
 316         bank_selector->addItems(QStringList() << "" << "Bank 1" << "Bank 2" << "Bank 3" << "Bank 4" << "Bank 5");
 317         bank_selector->setAutoFillBackground(true);
 318
 319         bank_combo_boxes.push_back(InstantiatedComboBox{ bank_selector, bank_field_number });
 320
 321         ui->treeWidget->setItemWidget(item, 1, bank_selector);
 322 }
 323
 324 void MIDIMappingDialog::add_controls(const string &heading,
 325                                      MIDIMappingDialog::ControlType control_type,
 326                                      MIDIMappingDialog::SpinnerGroup spinner_group,
 327                                      const MIDIMappingProto &mapping_proto,
 328                                      const vector<MIDIMappingDialog::Control> &controls)
 329 {
 330         QTreeWidgetItem *heading_item = new QTreeWidgetItem(ui->treeWidget);
 331         heading_item->setText(0, QString::fromStdString(heading));
 332         heading_item->setFirstColumnSpanned(true);
 333         heading_item->setExpanded(true);
 334         for (const Control &control : controls) {
 335                 QTreeWidgetItem *item = new QTreeWidgetItem(heading_item);
 336                 heading_item->addChild(item);
 337                 add_bank_selector(item, mapping_proto, control.bank_field_number);
 338                 item->setText(0, QString::fromStdString(control.label + "   "));
 339
 340                 for (unsigned bus_idx = 0; bus_idx < num_buses; ++bus_idx) {
 341                         QSpinBox *spinner = new QSpinBox(this);
 342                         spinner->setRange(0, 127);
 343                         spinner->setAutoFillBackground(true);
 344                         spinner->setSpecialValueText("\u200d");  // Zero-width joiner (ie., empty).
 345                         spinner->installEventFilter(this);  // So we know when the focus changes.
 346                         ui->treeWidget->setItemWidget(item, bus_idx + 2, spinner);
 347
 348                         if (control_type == ControlType::CONTROLLER) {
 349                                 controller_spinners.push_back(InstantiatedSpinner{ spinner, bus_idx, spinner_group, control.field_number });
 350                         } else {
 351                                 assert(control_type == ControlType::BUTTON);
 352                                 button_spinners.push_back(InstantiatedSpinner{ spinner, bus_idx, spinner_group, control.field_number });
 353                         }
 354                         spinners[bus_idx][control.field_number] = SpinnerAndGroup{ spinner, spinner_group };
 355                         connect(spinner, static_cast<void(QSpinBox::*)(int)>(&QSpinBox::valueChanged),
 356                                 bind(&MIDIMappingDialog::update_guess_button_state, this));
 357                 }
 358         }
 359         ui->treeWidget->addTopLevelItem(heading_item);
 360 }
 361
 362 void MIDIMappingDialog::fill_controls_from_mapping(const MIDIMappingProto &mapping_proto)
 363 {
 364         for (const InstantiatedSpinner &is : controller_spinners) {
 365                 is.spinner->setValue(get_controller_mapping(mapping_proto, is.bus_idx, is.field_number, 0));
 366         }
 367         for (const InstantiatedSpinner &is : button_spinners) {
 368                 is.spinner->setValue(get_button_mapping(mapping_proto, is.bus_idx, is.field_number, 0));
 369         }
 370         for (const InstantiatedComboBox &ic : bank_combo_boxes) {
 371                 ic.combo_box->setCurrentIndex(get_bank(mapping_proto, ic.field_number, -1) + 1);
 372         }
 373 }
 374
 375 void MIDIMappingDialog::controller_changed(unsigned controller)
 376 {
 377         for (const InstantiatedSpinner &is : controller_spinners) {
 378                 if (is.spinner->hasFocus()) {
 379                         is.spinner->setValue(controller);
 380                         is.spinner->selectAll();
 381                 }
 382         }
 383 }
 384
 385 void MIDIMappingDialog::note_on(unsigned note)
 386 {
 387         for (const InstantiatedSpinner &is : button_spinners) {
 388                 if (is.spinner->hasFocus()) {
 389                         is.spinner->setValue(note);
 390                         is.spinner->selectAll();
 391                 }
 392         }
 393 }
 394
 395 pair<int, int> MIDIMappingDialog::guess_offset(unsigned bus_idx, MIDIMappingDialog::SpinnerGroup spinner_group)
 396 {
 397         constexpr pair<int, int> not_found(-1, 0);
 398
 399         if (bus_is_empty(bus_idx, spinner_group)) {
 400                 return not_found;
 401         }
 402
 403         // See if we can find a non-empty bus to source from (prefer from the left).
 404         unsigned source_bus_idx;
 405         if (bus_idx > 0 && !bus_is_empty(bus_idx - 1, spinner_group)) {
 406                 source_bus_idx = bus_idx - 1;
 407         } else if (bus_idx < num_buses - 1 && !bus_is_empty(bus_idx + 1, spinner_group)) {
 408                 source_bus_idx = bus_idx + 1;
 409         } else {
 410                 return not_found;
 411         }
 412
 413         // See if we can find a consistent offset.
 414         bool found_offset = false;
 415         int offset = 0;
 416         int minimum_allowed_offset = numeric_limits<int>::min();
 417         int maximum_allowed_offset = numeric_limits<int>::max();
 418         for (const auto &field_number_and_spinner : spinners[bus_idx]) {
 419                 int field_number = field_number_and_spinner.first;
 420                 QSpinBox *spinner = field_number_and_spinner.second.spinner;
 421                 SpinnerGroup this_spinner_group = field_number_and_spinner.second.group;
 422                 assert(spinners[source_bus_idx].count(field_number));
 423                 QSpinBox *source_spinner = spinners[source_bus_idx][field_number].spinner;
 424                 assert(spinners[source_bus_idx][field_number].group == this_spinner_group);
 425
 426                 if (spinner_group != SpinnerGroup::ALL_GROUPS &&
 427                     spinner_group != this_spinner_group) {
 428                         continue;
 429                 }
 430                 if (spinner->value() == 0) {
 431                         if (source_spinner->value() != 0) {
 432                                 // If the source value is e.g. 3, offset can't be less than -2 or larger than 124.
 433                                 // Otherwise, we'd extrapolate values outside [1..127].
 434                                 minimum_allowed_offset = max(minimum_allowed_offset, 1 - source_spinner->value());
 435                                 maximum_allowed_offset = min(maximum_allowed_offset, 127 - source_spinner->value());
 436                         }
 437                         continue;
 438                 }
 439                 if (source_spinner->value() == 0) {
 440                         // The bus has a controller set that the source bus doesn't set.
 441                         return not_found;
 442                 }
 443
 444                 int candidate_offset = spinner->value() - source_spinner->value();
 445                 if (!found_offset) {
 446                         offset = candidate_offset;
 447                         found_offset = true;
 448                 } else if (candidate_offset != offset) {
 449                         return not_found;
 450                 }
 451         }
 452
 453         if (!found_offset) {
 454                 // Given that the bus wasn't empty, this shouldn't happen.
 455                 assert(false);
 456                 return not_found;
 457         }
 458
 459         if (offset < minimum_allowed_offset || offset > maximum_allowed_offset) {
 460                 return not_found;
 461         }
 462         return make_pair(source_bus_idx, offset);
 463 }
 464
 465 bool MIDIMappingDialog::bus_is_empty(unsigned bus_idx, SpinnerGroup spinner_group)
 466 {
 467         for (const auto &field_number_and_spinner : spinners[bus_idx]) {
 468                 QSpinBox *spinner = field_number_and_spinner.second.spinner;
 469                 SpinnerGroup this_spinner_group = field_number_and_spinner.second.group;
 470                 if (spinner_group != SpinnerGroup::ALL_GROUPS &&
 471                     spinner_group != this_spinner_group) {
 472                         continue;
 473                 }
 474                 if (spinner->value() != 0) {
 475                         return false;
 476                 }
 477         }
 478         return true;
 479 }
 480
 481 void MIDIMappingDialog::update_guess_button_state()
 482 {
 483         FocusInfo focus = find_focus();
 484         if (focus.bus_idx < 0) {
 485                 return;
 486         }
 487         {
 488                 pair<int, int> bus_and_offset = guess_offset(focus.bus_idx, SpinnerGroup::ALL_GROUPS);
 489                 ui->guess_bus_button->setEnabled(bus_and_offset.first != -1);
 490         }
 491         {
 492                 pair<int, int> bus_and_offset = guess_offset(focus.bus_idx, focus.spinner_group);
 493                 ui->guess_group_button->setEnabled(bus_and_offset.first != -1);
 494         }
 495         last_focus = focus;
 496 }
 497
 498 MIDIMappingDialog::FocusInfo MIDIMappingDialog::find_focus() const
 499 {
 500         for (const InstantiatedSpinner &is : controller_spinners) {
 501                 if (is.spinner->hasFocus()) {
 502                         return FocusInfo{ int(is.bus_idx), is.spinner_group, is.field_number };
 503                 }
 504         }
 505         for (const InstantiatedSpinner &is : button_spinners) {
 506                 if (is.spinner->hasFocus()) {
 507                         return FocusInfo{ int(is.bus_idx), is.spinner_group, is.field_number };
 508                 }
 509         }
 510         for (const InstantiatedSpinner &is : light_spinners) {
 511                 if (is.spinner->hasFocus()) {
 512                         return FocusInfo{ int(is.bus_idx), is.spinner_group, is.field_number };
 513                 }
 514         }
 515         return FocusInfo{ -1, SpinnerGroup::ALL_GROUPS, -1 };
 516 }