added UI for editing video parameters in nodes

app/widget/filefield/filefield.cpp

@@ -29,15 +29,16 @@
 namespace olive {
 
 FileField::FileField(QWidget* parent) :
-  QWidget(parent)
+  QWidget(parent),
+  directory_mode_(false)
 {
   QHBoxLayout* layout = new QHBoxLayout(this);
 
-  layout->setSpacing(0);
   layout->setMargin(0);
 
   line_edit_ = new QLineEdit();
   connect(line_edit_, &QLineEdit::textChanged, this, &FileField::LineEditChanged);
+  connect(line_edit_, &QLineEdit::textEdited, this, &FileField::FilenameChanged);
   layout->addWidget(line_edit_);
 
   browse_btn_ = new QPushButton();
@@ -48,22 +49,27 @@ FileField::FileField(QWidget* parent) :
 
 void FileField::BrowseBtnClicked()
 {
-  QString s = QFileDialog::getOpenFileName(this, tr("Open File"));
+  QString s;
+
+  if (directory_mode_) {
+    s = QFileDialog::getExistingDirectory(this, tr("Open Directory"));
+  } else {
+    s = QFileDialog::getOpenFileName(this, tr("Open File"));
+  }
 
   if (!s.isEmpty()) {
     line_edit_->setText(s);
+    emit FilenameChanged(s);
   }
 }
 
 void FileField::LineEditChanged(const QString& text)
 {
-  if (QFileInfo::exists(text)) {
+  if (QFileInfo::exists(text) || text.isEmpty()) {
     line_edit_->setStyleSheet(QString());
   } else {
     line_edit_->setStyleSheet(QStringLiteral("QLineEdit {color: red;}"));
   }
-
-  emit FilenameChanged(text);
 }
 
 }