Proper Size for Suggestion View

Header&Row evenly spread with fixed height.

resources/css/popup.css

@@ -3,6 +3,23 @@ QWidget {
     border: none;
 }
 
+QHeaderView {
+    background-color: white;
+}
+
+QHeaderView::section {
+    border: none;
+    color: #3b3b3b;
+    background-color: white;
+
+    margin-top: 5px; /* XXX: duplicated in css_constants.h */
+    padding: 5px 10px; /* XXX: duplicated in css_constants.h */
+
+    font-size: 16px;
+    line-height: 24px; /* XXX: duplicated in css_constants.h */
+    font-weight: 400;
+}
+
 QScrollBar {
     width: 5px;
     border: none;

src/css_constants.h

@@ -43,6 +43,17 @@ namespace QTreeView {
 }
 }
 
+/* In popup.css */
+namespace PopupCSS {
+namespace QHeaderView {
+namespace section {
+    const int marginTop = 5;
+    const int lineHeight = 24;
+    const int paddingVertical = 5;
+}
+}
+}
+
 }
 
 #endif // CSS_CONSTANTS_H

src/searchbar.cpp

@@ -8,6 +8,8 @@
 #include "suggestionlistworker.h"
 #include "css_constants.h"
 
+namespace HeaderSectionCSS = CSS::PopupCSS::QHeaderView::section;
+
 BookmarkButton::BookmarkButton(QWidget *parent) :
     QToolButton(parent)
 {
@@ -81,6 +83,24 @@ SearchBarLineEdit::SearchBarLineEdit(QWidget *parent) :
     m_suggestionView->setRootIsDecorated(false);
     m_suggestionView->setStyleSheet(KiwixApp::instance()->parseStyleFromFile(":/css/popup.css"));
 
+    const int contentHeight = HeaderSectionCSS::lineHeight;
+    m_suggestionView->setIconSize(QSize(contentHeight, contentHeight));
+
+    /* The suggestionView sizing unfortunately is not aware of headers. We 
+       have to do this manually. We also sized header the same as items.
+    */
+    connect(&m_suggestionModel, &QAbstractListModel::modelReset, [=](){
+        /* +1 for header. */
+        const int maxItem = m_completer.maxVisibleItems();
+        const int count = std::min(m_suggestionModel.rowCount(), maxItem) + 1;
+
+        const int itemHeight = m_suggestionView->sizeHintForRow(0);
+
+        /* Extra space styling above header and below last suggestion item. */
+        const int extraMargin = 2 * HeaderSectionCSS::marginTop;
+        m_suggestionView->setFixedHeight(itemHeight * count + extraMargin);
+    });
+
     connect(m_suggestionView->verticalScrollBar(), &QScrollBar::valueChanged,
             this, &SearchBarLineEdit::onScroll);
 

src/suggestionlistmodel.cpp

@@ -1,8 +1,11 @@
 #include "suggestionlistmodel.h"
 #include "kiwixapp.h"
+#include "css_constants.h"
 
 #include <QIcon>
 
+namespace HeaderSectionCSS = CSS::PopupCSS::QHeaderView::section;
+
 QString getZimIdFromUrl(QUrl url);
 
 SuggestionListModel::SuggestionListModel(QObject *parent)
@@ -35,9 +38,20 @@ QVariant SuggestionListModel::data(const QModelIndex &index, int role) const
         case Qt::UserRole:
             return m_suggestions.at(row).url;
         case Qt::DecorationRole:
+        {
             const auto library = KiwixApp::instance()->getLibrary();
             const auto zimId = getZimIdFromUrl(m_suggestions.at(row).url);
             return library->getBookIcon(zimId);
+        }
+        case Qt::SizeHintRole:
+        {
+            /* Padding in css can't change height, we have to achieve padding
+               by increasing height.
+            */
+            const int padding = HeaderSectionCSS::paddingVertical;
+            const int lineHeight = HeaderSectionCSS::lineHeight;
+            return QSize(0, lineHeight + 2 * padding);
+        }
     }
     return QVariant();
 }