Fix kcm_gtk crash when GTK2 / GTK3 themes is not available

This resolves Bug 1587

kcm_gtk/kcmgtk.cpp

@@ -232,13 +232,19 @@ void KcmGtk::getInstalledThemes()
 		}
 	}
 	
+	bool installed = false;
 	widget->styleBox->clear();
 	TQStringList otherStyles = themes.keys();
-	otherStyles.remove(otherStyles.find("Qt"));
-	widget->styleBox->insertStringList(otherStyles);
-	
-	bool installed = (themes.find("Qt") != themes.end());
+	if(!otherStyles.empty()) {
+		otherStyles.remove(otherStyles.find("Qt"));
+		installed = !otherStyles.empty();
+	}
+	if(installed) {
+		widget->styleBox->insertStringList(otherStyles);
+	}
 	widget->styleKde->setEnabled(installed);
+	widget->styleBox->setEnabled(installed);
+	widget->styleOther->setEnabled(installed);
 	widget->warning1->setHidden(installed);
 	widget->warning2->setHidden(installed);
 	widget->warning3->setHidden(installed);
@@ -261,13 +267,19 @@ void KcmGtk::getInstalledThemes()
 		}
 	}
 	
+	bool gtk3installed = false;
 	widget->styleBox3->clear();
 	TQStringList otherGtk3Styles = gtk3Themes.keys();
-	otherGtk3Styles.remove(otherGtk3Styles.find("tdegtk"));
-	widget->styleBox3->insertStringList(otherGtk3Styles);
-	
-	bool gtk3installed = (gtk3Themes.find("tdegtk") != gtk3Themes.end());
+	if(!otherGtk3Styles.empty()) {
+		otherGtk3Styles.remove(otherGtk3Styles.find("tdegtk"));
+		gtk3installed = !otherGtk3Styles.empty();
+	}
+	if(gtk3installed) {
+		widget->styleBox3->insertStringList(otherGtk3Styles);
+	}
 	widget->styleKde3->setEnabled(gtk3installed);
+	widget->styleBox3->setEnabled(gtk3installed);
+	widget->styleOther3->setEnabled(gtk3installed);
 	widget->warning4->setHidden(gtk3installed);
 	widget->warning5->setHidden(gtk3installed);
 	widget->warning6->setHidden(gtk3installed);