[categorized renderer] When color ramp is set to random, randomize color

nirvn · nirvn · commit 6db7e9edb18c · 2019-09-16T02:52:49.000Z
of appended categories to pre-existing list when hitting the classify button (fixes #31579)
diff --git a/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp b/src/gui/symbology/qgscategorizedsymbolrendererwidget.cpp
@@ -739,6 +739,9 @@ void QgsCategorizedSymbolRendererWidget::addCategories()
   {
     QgsCategoryList prevCats = mRenderer->categories();
     keepExistingColors = !prevCats.isEmpty();
+    QgsRandomColorRamp randomColors;
+    if ( keepExistingColors && btnColorRamp->isRandomColorRamp() )
+      randomColors.setTotalColorCount( cats.size() );
     for ( int i = 0; i < cats.size(); ++i )
     {
       bool contains = false;
@@ -753,7 +756,14 @@ void QgsCategorizedSymbolRendererWidget::addCategories()
       }
 
       if ( !contains )
+      {
+        if ( keepExistingColors && btnColorRamp->isRandomColorRamp() )
+        {
+          // insure that append symbols have random colors
+          cats.at( i ).symbol()->setColor( randomColors.color( i ) );
+        }
         prevCats.append( cats.at( i ) );
+      }
     }
     cats = prevCats;
   }

Original file line number	Diff line number	Diff line change
`@@ -739,6 +739,9 @@ void QgsCategorizedSymbolRendererWidget::addCategories()`
`739`	`739`	`{`
`740`	`740`	`QgsCategoryList prevCats = mRenderer->categories();`
`741`	`741`	`keepExistingColors = !prevCats.isEmpty();`
	`742`	`+ QgsRandomColorRamp randomColors;`
	`743`	`+ if ( keepExistingColors && btnColorRamp->isRandomColorRamp() )`
	`744`	`+ randomColors.setTotalColorCount( cats.size() );`
`742`	`745`	`for ( int i = 0; i < cats.size(); ++i )`
`743`	`746`	`{`
`744`	`747`	`bool contains = false;`
`@@ -753,7 +756,14 @@ void QgsCategorizedSymbolRendererWidget::addCategories()`
`753`	`756`	`}`
`754`	`757`
`755`	`758`	`if ( !contains )`
	`759`	`+ {`
	`760`	`+ if ( keepExistingColors && btnColorRamp->isRandomColorRamp() )`
	`761`	`+ {`
	`762`	`+ // insure that append symbols have random colors`
	`763`	`+ cats.at( i ).symbol()->setColor( randomColors.color( i ) );`
	`764`	`+ }`
`756`	`765`	`prevCats.append( cats.at( i ) );`
	`766`	`+ }`
`757`	`767`	`}`
`758`	`768`	`cats = prevCats;`
`759`	`769`	`}`