From 3485a52e16b4d8ebfaf6f96b61ab221c5189dce5 Mon Sep 17 00:00:00 2001
From: mgrojo <mgrojo@gmail.com>
Date: Sat, 20 Jun 2020 16:58:52 +0200
Subject: [PATCH] Bar charts did not display labels in x axis when NULL values
 present

The problem was signaled by an error when calling addTicks:
[...]AddTicks[...] passed unequal length vectors for positions and labels

See comment in issue #2286
---
 src/PlotDock.cpp | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/src/PlotDock.cpp b/src/PlotDock.cpp
index f101d74e..2ed6b58c 100644
--- a/src/PlotDock.cpp
+++ b/src/PlotDock.cpp
@@ -360,11 +360,16 @@ void PlotDock::updatePlot(SqliteTableModel* model, BrowseDataTableSettings* sett
                 {
                     tdata[j] = j;
 
-                    // NULL values produce gaps in the graph. We use NaN values in
-                    // that case as required by QCustomPlot.
-                    if(x != RowNumId && model->data(model->index(j, x), Qt::EditRole).isNull())
-                        xdata[j] = qQNaN();
-                    else {
+                    if(x != RowNumId && model->data(model->index(j, x), Qt::EditRole).isNull()) {
+                        // NULL values produce gaps in the linear graphs. We use NaN values in
+                        // that case as required by QCustomPlot.
+                        // Bar plots will display the configured string for NULL values.
+                        if(xtype == QVariant::String) {
+                            xdata[j] = j+1;
+                            labels << model->data(model->index(j, x), Qt::DisplayRole).toString();
+                        } else
+                            xdata[j] = qQNaN();
+                    } else {
 
                         // convert x type axis if it's datetime
                         switch (xtype) {