[LyX/master] Add some more hints to empty margin widgets (#11424)

[Juergen Spitzmueller]

commit a4e6f0dead780b82d1d5abcd0258845f13b3ecc0
Author: Juergen Spitzmueller <spitz at lyx.org>
Date:   Sun Jan 17 17:49:45 2021 +0100

    Add some more hints to empty margin widgets (#11424)
---
 src/frontends/qt/GuiDocument.cpp |   49 ++++++++++++++++++++++++++++++++++++++
 src/frontends/qt/ui/MarginsUi.ui |    2 +-
 2 files changed, 50 insertions(+), 1 deletions(-)

diff --git a/src/frontends/qt/GuiDocument.cpp b/src/frontends/qt/GuiDocument.cpp
index 9af1eba..953e51c 100644
--- a/src/frontends/qt/GuiDocument.cpp
+++ b/src/frontends/qt/GuiDocument.cpp
@@ -2079,6 +2079,30 @@ void GuiDocument::setMargins()
 		marginsModule->marginCB->setChecked(!bp_.use_geometry);
 		setCustomMargins(!bp_.use_geometry);
 	}
+
+	// set some placeholder text that hint on defaults
+	QString const placeholder = marginsModule->marginCB->isChecked() ?
+		qt_("Class defaults") : qt_("Package defaults");
+	// set tooltip depending on gemoetry state
+	QString const tooltip = marginsModule->marginCB->isChecked() ?
+		qt_("If no value is given, the defaults as set by the class are used.")
+		: qt_("If no value is given, the defaults as set by the geometry package or a package/class overriding geometry's defaults are used.");
+	marginsModule->topLE->setPlaceholderText(placeholder);
+	marginsModule->bottomLE->setPlaceholderText(placeholder);
+	marginsModule->innerLE->setPlaceholderText(placeholder);
+	marginsModule->outerLE->setPlaceholderText(placeholder);
+	marginsModule->headheightLE->setPlaceholderText(placeholder);
+	marginsModule->headsepLE->setPlaceholderText(placeholder);
+	marginsModule->footskipLE->setPlaceholderText(placeholder);
+	marginsModule->columnsepLE->setPlaceholderText(placeholder);
+	marginsModule->topLE->setToolTip(tooltip);
+	marginsModule->bottomLE->setToolTip(tooltip);
+	marginsModule->innerLE->setToolTip(tooltip);
+	marginsModule->outerLE->setToolTip(tooltip);
+	marginsModule->headheightLE->setToolTip(tooltip);
+	marginsModule->headsepLE->setToolTip(tooltip);
+	marginsModule->footskipLE->setToolTip(tooltip);
+	marginsModule->columnsepLE->setToolTip(tooltip);
 }
 
 
@@ -2141,6 +2165,31 @@ void GuiDocument::setCustomMargins(bool custom)
 	marginsModule->columnsepL->setEnabled(enableColSep);
 	marginsModule->columnsepLE->setEnabled(enableColSep);
 	marginsModule->columnsepUnit->setEnabled(enableColSep);
+
+	// set some placeholder text that hint on defaults
+	QString const placeholder = marginsModule->marginCB->isChecked() ?
+		qt_("Class defaults") : qt_("Package defaults");
+	// set tooltip depending on gemoetry state
+	QString const tooltip = marginsModule->marginCB->isChecked() ?
+		qt_("If no value is given, the defaults as set by the class are used.")
+		: qt_("If no value is given, the defaults as set by the geometry package or a package/class overriding geometry's defaults are used.");
+	marginsModule->topLE->setPlaceholderText(placeholder);
+	marginsModule->bottomLE->setPlaceholderText(placeholder);
+	marginsModule->innerLE->setPlaceholderText(placeholder);
+	marginsModule->outerLE->setPlaceholderText(placeholder);
+	marginsModule->headheightLE->setPlaceholderText(placeholder);
+	marginsModule->headsepLE->setPlaceholderText(placeholder);
+	marginsModule->footskipLE->setPlaceholderText(placeholder);
+	marginsModule->columnsepLE->setPlaceholderText(placeholder);
+	marginsModule->topLE->setToolTip(tooltip);
+	marginsModule->bottomLE->setToolTip(tooltip);
+	marginsModule->innerLE->setToolTip(tooltip);
+	marginsModule->outerLE->setToolTip(tooltip);
+	marginsModule->headheightLE->setToolTip(tooltip);
+	marginsModule->headsepLE->setToolTip(tooltip);
+	marginsModule->footskipLE->setToolTip(tooltip);
+	marginsModule->columnsepLE->setToolTip(tooltip);
+
 }
 
 
diff --git a/src/frontends/qt/ui/MarginsUi.ui b/src/frontends/qt/ui/MarginsUi.ui
index c8f0deb..ca9830b 100644
--- a/src/frontends/qt/ui/MarginsUi.ui
+++ b/src/frontends/qt/ui/MarginsUi.ui
@@ -36,7 +36,7 @@
      </property>
      <property name="toolTip">
       <string>Use the margin settings provided by the document class.
-Note that if this is unchecked, leaving a field empty may use different defaults values (determined either by the geometry package or by classes/packages overriding geometry's defaults).</string>
+Note that if this is unchecked, different defaults may be used.</string>
      </property>
      <property name="text">
       <string>&Default margins</string>