Add environment variable for disabling desktop method integration

Don't create instance of DesktopInputPanel if variable
QT_VIRTUALKEYBOARD_DESKTOP_DISABLE is set. In this case we can use only
application integration method without recompiling with
CONFIG+=disable-desktop.

Change-Id: I935880174b7928a4dd7a4ff9ff21b6f27b5fead6
Reviewed-by: Jarkko Koivikko <jarkko.koivikko@code-q.fi>
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

3 files changed, 16 insertions, 3 deletions

diff --git a/src/virtualkeyboard/doc/src/deployment-guide.qdoc b/src/virtualkeyboard/doc/src/deployment-guide.qdoc
index 6e1a2642..718068d7 100644
--- a/src/virtualkeyboard/doc/src/deployment-guide.qdoc
+++ b/src/virtualkeyboard/doc/src/deployment-guide.qdoc
@@ -91,7 +91,8 @@ for using the plugin:
 The integration method is automatically selected by the project files.
 However, in desktop environments, it is possible to override the desktop
 integration method and use the application integration method instead,
-by adding \c CONFIG+=disable-desktop to the \c qmake command line.
+by using the \c QT_VIRTUALKEYBOARD_DESKTOP_DISABLE environment variable,
+or by adding \c CONFIG+=disable-desktop to the \c qmake command line.
 
 \section2 Using Qt Virtual Keyboard with Qt Wayland
 
@@ -254,6 +255,9 @@ There are several environment variables defined by the module that are listed be
         \li QT_VIRTUALKEYBOARD_LAYOUT_PATH
         \li Specifies the location of the layouts to be used with the virtual keyboard.
     \row
+        \li QT_VIRTUALKEYBOARD_DESKTOP_DISABLE
+        \li Disables the desktop integration method.
+    \row
         \li LIPI_ROOT
         \li Specifies the location of lipi-toolkit.
 
diff --git a/src/virtualkeyboard/platforminputcontext.cpp b/src/virtualkeyboard/platforminputcontext.cpp
index 736af37c..fc229f52 100644
--- a/src/virtualkeyboard/platforminputcontext.cpp
+++ b/src/virtualkeyboard/platforminputcontext.cpp
@@ -46,6 +46,8 @@ namespace QtVirtualKeyboard {
 
 Q_LOGGING_CATEGORY(qlcVirtualKeyboard, "qt.virtualkeyboard")
 
+static const char disableDesktopEnvVarName[] = "QT_VIRTUALKEYBOARD_DESKTOP_DISABLE";
+
 /*!
     \class QtVirtualKeyboard::PlatformInputContext
     \internal
@@ -58,8 +60,14 @@ PlatformInputContext::PlatformInputContext() :
     m_locale(),
     m_inputDirection(m_locale.textDirection()),
     m_filterEvent(nullptr),
-    m_visible(false)
+    m_visible(false),
+    m_desktopModeDisabled(false)
 {
+    if (!qEnvironmentVariableIsEmpty(disableDesktopEnvVarName)) {
+        bool ok;
+        int desktopModeDisabled = qgetenv(disableDesktopEnvVarName).toInt(&ok);
+        m_desktopModeDisabled = ok && desktopModeDisabled != 0;
+    }
 }
 
 PlatformInputContext::~PlatformInputContext()
@@ -90,7 +98,7 @@ void PlatformInputContext::update(Qt::InputMethodQueries queries)
     VIRTUALKEYBOARD_DEBUG() << "PlatformInputContext::update():" << queries;
     bool enabled = inputMethodQuery(Qt::ImEnabled).toBool();
 #ifdef QT_VIRTUALKEYBOARD_DESKTOP
-    if (enabled && !m_inputPanel) {
+    if (enabled && !m_inputPanel && !m_desktopModeDisabled) {
         m_inputPanel = new DesktopInputPanel(this);
         m_inputPanel->createView();
         if (m_inputContext) {
diff --git a/src/virtualkeyboard/platforminputcontext_p.h b/src/virtualkeyboard/platforminputcontext_p.h
index 50ccf561..9fadc00f 100644
--- a/src/virtualkeyboard/platforminputcontext_p.h
+++ b/src/virtualkeyboard/platforminputcontext_p.h
@@ -118,6 +118,7 @@ private:
     Qt::LayoutDirection m_inputDirection;
     QEvent *m_filterEvent;
     bool m_visible;
+    bool m_desktopModeDisabled;
 };
 
 } // namespace QtVirtualKeyboard