Styles for headers

Added new styles for headers

resources/css/_contentManager.css

@@ -0,0 +1,46 @@
+QTreeView::branch:open:has-children {
+    image: url(:/icons/caret-down-solid.svg);
+    margin: 7px;
+}
+
+QTreeView::branch:closed:has-children {
+    image: url(:/icons/caret-right-solid.svg);
+    margin: 7px;
+}
+
+QTreeView::item:has-children {
+    border-bottom: 1px solid #b7bec9;
+}
+
+QTreeView {
+    font-family: 'Selawik';
+    padding: 4px;
+}
+
+QHeaderView::section {
+    color: grey;
+    background-color:  #fff;
+    border-width: 0px 0px 2px 0px;
+    border-color: black;
+    border-style: plain;
+    font-size: 16px;
+    font-family: 'Selawik';
+    padding: 4px;
+}
+
+QHeaderView::section:checked
+{
+    color: black;
+    font-weight: bold;
+    background-color: #5589E8;
+}
+
+QHeaderView::down-arrow {
+    image: url(:/icons/caret-down-solid.svg);
+    margin: 5px;
+}
+
+QHeaderView::up-arrow {
+    image: url(:/icons/caret-up-solid.svg);
+    margin: 5px;
+}

resources/kiwix.qrc

@@ -57,5 +57,8 @@
         <file>icons/library-icon.svg</file>
         <file>icons/open-file.svg</file>
         <file>js/tools.js</file>
+        <file>icons/caret-down-solid.svg</file>
+        <file>icons/caret-right-solid.svg</file>
+        <file>icons/caret-up-solid.svg</file>
     </qresource>
 </RCC>

src/contentmanager.cpp

@@ -45,6 +45,9 @@ ContentManager::ContentManager(Library* library, kiwix::Downloader* downloader,
     header->setSectionsClickable(true);
     header->setHighlightSections(true);
     mp_view->setWordWrap(true);
+    mp_view->resizeColumnToContents(4);
+    mp_view->setColumnWidth(0, 80);
+    // TODO: set width for all columns based on viewport
 
     setCurrentLanguage(QLocale().name().split("_").at(0));
     connect(mp_library, &Library::booksChanged, this, [=]() {emit(this->booksChanged());});