allow that no document is open

this is an extension of allowing we have no views

apps/lib/CMakeLists.txt

@@ -66,7 +66,7 @@ if (TARGET KUserFeedbackWidgets)
     target_compile_definitions(kateprivate PUBLIC -DWITH_KUSERFEEDBACK)
 endif()
 
-ki18n_wrap_ui(kateprivate ui/sessionconfigwidget.ui session/katesessionmanagedialog.ui)
+ki18n_wrap_ui(kateprivate ui/sessionconfigwidget.ui ui/welcome.ui session/katesessionmanagedialog.ui)
 
 target_sources(
   kateprivate
@@ -97,6 +97,7 @@ target_sources(
     katesplitter.cpp
     kateviewmanager.cpp
     kateviewspace.cpp
+    katewelcomeview.cpp
     tabmimedata.cpp
 
     kateoutputview.cpp

apps/lib/katedocmanager.cpp

@@ -39,9 +39,6 @@ KateDocManager::KateDocManager(QObject *parent)
 {
     // set our application wrapper
     KTextEditor::Editor::instance()->setApplication(KateApp::self()->wrapper());
-
-    // create one doc, we always have at least one around!
-    createDoc();
 }
 
 KateDocManager::~KateDocManager()
@@ -212,14 +209,6 @@ bool KateDocManager::closeDocuments(const QList<KTextEditor::Document *> documen
         last++;
     }
 
-    /**
-     * never ever empty the whole document list
-     * do this before documentsDeleted is emitted, to have no flicker
-     */
-    if (m_docList.empty()) {
-        createDoc();
-    }
-
     Q_EMIT documentsDeleted(QList<KTextEditor::Document *>{documents.begin() + last, documents.end()});
 
     return success;
@@ -409,13 +398,7 @@ void KateDocManager::restoreDocumentList(KConfig *config)
 
     for (unsigned int i = 0; i < count; i++) {
         KConfigGroup cg(config, QStringLiteral("Document %1").arg(i));
-        KTextEditor::Document *doc = nullptr;
-
-        if (i == 0) {
-            doc = m_docList.front();
-        } else {
-            doc = createDoc();
-        }
+        KTextEditor::Document *doc = createDoc();
 
         connect(doc, SIGNAL(completed()), this, SLOT(documentOpened()));
         connect(doc, &KParts::ReadOnlyPart::canceled, this, &KateDocManager::documentOpened);

apps/lib/katemainwindow.cpp

@@ -27,6 +27,7 @@
 #include "katestashmanager.h"
 #include "kateupdatedisabler.h"
 #include "kateviewspace.h"
+#include "katewelcomeview.h"
 #include "ktexteditor_utils.h"
 
 #include <KAboutData>
@@ -177,6 +178,14 @@ KateMainWindow::KateMainWindow(KConfig *sconfig, const QString &sgroup)
     if (KateApp::isKWrite()) {
         setSidebarsVisibleInternal(false, true);
     }
+
+    // ensure we have the welcome view if no active view is there
+    // delay this after initialisation
+    QTimer::singleShot(0, this, [this]() {
+        if (activeView())
+            return;
+        addWidget(new KateWelcomeView(m_viewManager->activeViewSpace(), nullptr));
+    });
 }
 
 KateMainWindow::~KateMainWindow()

apps/lib/katetabbar.cpp

@@ -485,4 +485,5 @@ void KateTabBar::setCurrentWidget(QWidget *widget)
     setTabIcon(idx, widget->windowIcon());
     setTabData(idx, QVariant::fromValue(widget));
     setCurrentIndex(idx);
+    Q_EMIT currentChanged(idx);
 }

apps/lib/kateviewmanager.cpp

@@ -1298,7 +1298,7 @@ void KateViewManager::restoreViewConfiguration(const KConfigGroup &config)
         // activate correct view (wish #195435, #188764)
         activateView(m_viewSpaceList.at(lastViewSpace)->currentView());
         // give view the focus to avoid focus stealing by toolviews / plugins
-        m_viewSpaceList.at(lastViewSpace)->currentView()->setFocus();
+        m_viewSpaceList.at(lastViewSpace)->setFocus();
     }
 
     // emergency
@@ -1312,14 +1312,6 @@ void KateViewManager::restoreViewConfiguration(const KConfigGroup &config)
         addWidget(vs);
         vs->setActive(true);
         m_viewSpaceList.push_back(vs);
-
-        /**
-         * activate at least one document!
-         */
-        activateView(KateApp::self()->documentManager()->documentList().back());
-        if (!vs->currentView()) {
-            createView(activeView()->document(), vs);
-        }
     }
 
     updateViewSpaceActions();

apps/lib/kateviewspace.cpp

@@ -448,7 +448,7 @@ void KateViewSpace::changeView(int idx)
     if (!doc) {
         auto w = m_tabBar->tabData(idx).value<QWidget *>();
         if (!w) {
-            Q_ASSERT(false);
+            // can happen during widget creation if no view is there initially
             return;
         }
         stack->setCurrentWidget(w);
@@ -1122,26 +1122,8 @@ void KateViewSpace::restoreConfig(KateViewManager *viewMan, const KConfigBase *c
         }
     }
 
-    // avoid empty view space
-    if (m_docToView.empty()) {
-        auto *doc = KateApp::self()->documentManager()->documentList().first();
-        if (!fn.isEmpty()) {
-            QUrl url(fn);
-            auto *docInfo = KateApp::self()->documentManager()->documentInfo(doc);
-            if (KateApp::self()->hasCursorInArgs()) {
-                docInfo->startCursor = KateApp::self()->cursorFromArgs();
-            } else if (url.hasQuery()) {
-                docInfo->startCursor = KateApp::self()->cursorFromQueryString(url);
-            }
-        }
-        viewMan->createView(doc, this);
-    }
-
-    // there must be a view now
-    Q_ASSERT(currentView());
-
     // ensure we update the urlbar at least once
-    m_urlBar->updateForDocument(currentView()->document());
+    m_urlBar->updateForDocument(currentView() ? currentView()->document() : nullptr);
 
     m_group = groupname; // used for restroing view configs later
 }

apps/lib/katewelcomeview.cpp

+/*
+    SPDX-FileCopyrightText: 2022 Christoph Cullmann <cullmann@kde.org>
+
+    SPDX-License-Identifier: LGPL-2.0-or-later
+*/
+
+#include "katewelcomeview.h"
+
+KateWelcomeView::KateWelcomeView(KateViewSpace *viewSpace, QWidget *parent)
+    : QWidget(parent)
+    , m_viewSpace(viewSpace)
+{
+    m_ui.setupUi(this);
+}

apps/lib/katewelcomeview.h

+/*
+    SPDX-FileCopyrightText: 2022 Christoph Cullmann <cullmann@kde.org>
+
+    SPDX-License-Identifier: LGPL-2.0-or-later
+*/
+
+#pragma once
+
+#include "ui_welcome.h"
+
+class KateViewSpace;
+
+/**
+ * Placeholder if a view space has no real views.
+ * Allows for a nice welcome experience :P
+ */
+class KateWelcomeView : public QWidget
+{
+    Q_OBJECT
+
+public:
+    /**
+     * Construct new output, we do that once per main window
+     * @param viewSpace parent view space
+     * @param parent parent widget
+     */
+    KateWelcomeView(KateViewSpace *viewSpace, QWidget *parent);
+
+private:
+    // our viewspace we belong to
+    KateViewSpace *const m_viewSpace = nullptr;
+
+    // designer UI for this widget
+    Ui::WelcomeViewWidget m_ui;
+};

apps/lib/ui/welcome.ui

+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>WelcomeViewWidget</class>
+ <widget class="QWidget" name="Form">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>990</width>
+    <height>593</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Form</string>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout_4">
+   <item>
+    <layout class="QVBoxLayout" name="verticalLayout_3">
+     <item>
+      <widget class="QLabel" name="label">
+       <property name="text">
+        <string>Kate - KDE Advance Text Editor</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <layout class="QHBoxLayout" name="horizontalLayout">
+       <item>
+        <widget class="QGroupBox" name="groupBox">
+         <property name="title">
+          <string>Start</string>
+         </property>
+         <layout class="QVBoxLayout" name="verticalLayout">
+          <item>
+           <widget class="QPushButton" name="pushButton">
+            <property name="text">
+             <string>PushButton</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QPushButton" name="pushButton_2">
+            <property name="text">
+             <string>PushButton</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <widget class="QPushButton" name="pushButton_3">
+            <property name="text">
+             <string>PushButton</string>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <spacer name="verticalSpacer">
+            <property name="orientation">
+             <enum>Qt::Vertical</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>20</width>
+              <height>40</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+         </layout>
+        </widget>
+       </item>
+       <item>
+        <widget class="QGroupBox" name="groupBox_2">
+         <property name="title">
+          <string>Recent</string>
+         </property>
+         <layout class="QVBoxLayout" name="verticalLayout_2">
+          <item>
+           <widget class="QListWidget" name="listWidget"/>
+          </item>
+         </layout>
+        </widget>
+       </item>
+      </layout>
+     </item>
+    </layout>
+   </item>
+  </layout>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>