add light and dark themes

forms/mainwindow.ui

@@ -1281,7 +1281,7 @@
                  <item row="0" column="1">
                   <widget class="QLabel" name="label">
                    <property name="text">
-                    <string>Transparency</string>
+                    <string>Opacity</string>
                    </property>
                   </widget>
                  </item>
@@ -2827,6 +2827,8 @@
     <addaction name="actionCursor_Tile_Outline"/>
     <addaction name="actionPlayer_View_Rectangle"/>
     <addaction name="actionBetter_Cursors"/>
+    <addaction name="separator"/>
+    <addaction name="actionThemes"/>
    </widget>
    <widget class="QMenu" name="menuTools">
     <property name="title">
@@ -3083,6 +3085,11 @@
     <string>Ctrl+Shift+N</string>
    </property>
   </action>
+  <action name="actionThemes">
+   <property name="text">
+    <string>Themes...</string>
+   </property>
+  </action>
  </widget>
  <layoutdefault spacing="6" margin="11"/>
  <customwidgets>

include/mainwindow.h

@@ -141,6 +141,7 @@ private slots:
     void on_toolButton_ExpandAll_clicked();
     void on_toolButton_CollapseAll_clicked();
     void on_actionAbout_Porymap_triggered();
+    void on_actionThemes_triggered();
     void on_pushButton_AddCustomHeaderField_clicked();
     void on_pushButton_DeleteCustomHeaderField_clicked();
     void on_tableWidget_CustomHeaderFields_cellChanged(int row, int column);

porymap.pro

@@ -144,7 +144,8 @@ FORMS    += forms/mainwindow.ui \
     forms/mapimageexporter.ui
 
 RESOURCES += \
-    resources/images.qrc
+    resources/images.qrc \
+    resources/themes.qrc
 
 INCLUDEPATH += include
 INCLUDEPATH += include/core

resources/themes.qrc

@@ -0,0 +1,6 @@
+<RCC>
+    <qresource prefix="/">
+        <file>themes/dark.qss</file>
+        <file>themes/light.qss</file>
+    </qresource>
+</RCC>

resources/themes/dark.qss

@@ -0,0 +1,95 @@
+/* DARK theme for porymap */
+
+/* General Widgets */
+
+QWidget {
+    background: #31332b;
+    color: #F8F8F2;
+}
+
+QWidget::item:selected {
+    background: #49483E;
+}
+
+QWidget::item:focus {
+    background: #49483E;
+    border: none;
+}
+
+/* Combo Boxes */
+
+QComboBox {
+    background: #272822;
+    color: #F8F8F2;
+}
+
+QComboBox QAbstractItemView {
+    background: #31332b;
+    color: #75715E;
+    selection-background-color: #49483E;
+}
+
+/* Spin Boxes */
+
+QSpinBox {
+    background: #272822;
+    color: #F8F8F2;
+}
+
+/* Line Edits */
+
+QLineEdit {
+    background: #272822;
+    color: #F8F8F2;
+}
+
+/* Frames, Labels */
+
+#label_spritePixmap {
+    background: #272822;
+    color: #F8F8F2;
+}
+
+/* Checkboxes */
+
+QCheckBox, QRadioButton {
+    border: none;
+}
+
+QRadioButton::indicator::unchecked, QCheckBox::indicator::unchecked {
+    border: 1px solid #49483E;
+    background: none;
+}
+
+QRadioButton::indicator:unchecked:hover, QCheckBox::indicator:unchecked:hover {
+    border: 1px solid #F8F8F2;
+}
+
+QRadioButton::indicator::checked, QCheckBox::indicator::checked {
+    border: 1px solid #49483E;
+    background: #49483E;
+}
+
+QRadioButton::indicator:checked:hover, QCheckBox::indicator:checked:hover {
+    border: 1px solid #F8F8F2;
+    background: #F8F8F2;
+}
+
+/* Map List View */
+
+QTreeView {
+    background: #272822;
+}
+
+QTreeView::item:hover {
+    background: #49483E;
+}
+
+QTreeView::item:selected {
+    background: #49483E;
+    color: #F8F8F2;
+}
+
+QTreeView::branch {
+    background: #272822;
+}

resources/themes/light.qss

@@ -0,0 +1,95 @@
+/* LIGHT theme for porymap */
+
+/* General Widgets */
+
+QWidget {
+    background: #F5F5F5;
+    color: #3C3C3C;
+}
+
+QWidget::item:selected {
+    background: #CACACA;
+}
+
+QWidget::item:focus {
+    background: #CACACA;
+    border: none;
+}
+
+/* Combo Boxes */
+
+QComboBox {
+    background: #F5F5F5;
+    color: #3C3C3C;
+}
+
+QComboBox QAbstractItemView {
+    background: #F5F5F5;
+    color: #898989;
+    selection-background-color: #707070;
+}
+
+/* Spin Boxes */
+
+QSpinBox {
+    background: #F5F5F5;
+    color: #3C3C3C;
+}
+
+/* Line Edits */
+
+QLineEdit {
+    background: #F5F5F5;
+    color: #3C3C3C;
+}
+
+/* Frames, Labels */
+
+#label_spritePixmap {
+    background: #F5F5F5;
+    color: #3C3C3C;
+}
+
+/* Checkboxes */
+
+QCheckBox, QRadioButton {
+    border: none;
+}
+
+QRadioButton::indicator::unchecked, QCheckBox::indicator::unchecked {
+    border: 1px solid #CACACA;
+    background: none;
+}
+
+QRadioButton::indicator:unchecked:hover, QCheckBox::indicator:unchecked:hover {
+    border: 1px solid #3C3C3C;
+}
+
+QRadioButton::indicator::checked, QCheckBox::indicator::checked {
+    border: 1px solid #CACACA;
+    background: #CACACA;
+}
+
+QRadioButton::indicator:checked:hover, QCheckBox::indicator:checked:hover {
+    border: 1px solid #3C3C3C;
+    background: #3C3C3C;
+}
+
+/* Map List View */
+
+QTreeView {
+    background: #F5F5F5;
+}
+
+QTreeView::item:hover {
+    background: #CACACA;
+}
+
+QTreeView::item:selected {
+    background: #CACACA;
+    color: #3C3C3C;
+}
+
+QTreeView::branch {
+    background: #F5F5F5;
+}

src/mainwindow.cpp

@@ -11,6 +11,7 @@
 #include "customattributestable.h"
 
 #include <QFileDialog>
+#include <QDirIterator>
 #include <QStandardItemModel>
 #include <QShortcut>
 #include <QSpinBox>
@@ -2119,6 +2120,45 @@ void MainWindow::on_actionAbout_Porymap_triggered()
     window->show();
 }
 
+void MainWindow::on_actionThemes_triggered()
+{
+    QStringList themes;
+    QRegularExpression re(":/themes/([A-z0-9_]+).qss");
+    themes.append("default");
+    QDirIterator it(":/themes", QDirIterator::Subdirectories);
+    while (it.hasNext()) {
+        QString themeName = re.match(it.next()).captured(1);
+        themes.append(themeName);
+    }
+
+    QDialog themeSelectorWindow(this);
+    QFormLayout form(&themeSelectorWindow);
+
+    NoScrollComboBox *themeSelector = new NoScrollComboBox();
+    themeSelector->addItems(themes);
+    form.addRow(new QLabel("Themes"), themeSelector);
+
+    QDialogButtonBox buttonBox(QDialogButtonBox::Apply | QDialogButtonBox::Close, Qt::Horizontal, &themeSelectorWindow);
+    form.addRow(&buttonBox);
+    connect(&buttonBox, &QDialogButtonBox::clicked, [&themeSelectorWindow, &buttonBox, themeSelector, this](QAbstractButton *button){
+        if (button == buttonBox.button(QDialogButtonBox::Apply)) {
+            QString theme = themeSelector->currentText();
+            if (theme == "default") {
+                setStyleSheet("");
+                return;
+            }
+
+            QFile File(QString(":/themes/%1.qss").arg(theme));
+            File.open(QFile::ReadOnly);
+            QString stylesheet = QLatin1String(File.readAll());
+            setStyleSheet(stylesheet);
+        }
+    });
+    connect(&buttonBox, SIGNAL(rejected()), &themeSelectorWindow, SLOT(reject()));
+
+    themeSelectorWindow.exec();
+}
+
 void MainWindow::on_pushButton_AddCustomHeaderField_clicked()
 {
     int rowIndex = this->ui->tableWidget_CustomHeaderFields->rowCount();