gui: prep work for inserting rows

main.go

@@ -11,6 +11,7 @@ import (
 	"github.com/pkg/browser"
 	"github.com/ying32/govcl/vcl"
 	"github.com/ying32/govcl/vcl/types"
+	"github.com/ying32/govcl/vcl/types/colors"
 )
 
 const (
@@ -31,6 +32,7 @@ type TMainForm struct {
 	Tabs          *vcl.TPageControl
 	propertiesBox *vcl.TMemo
 	contentBox    *vcl.TStringGrid
+	insertRows    []int32 // Rows in the StringGrid that are to-be-inserted
 	queryInput    *vcl.TMemo
 	queryResult   *vcl.TStringGrid
 
@@ -226,6 +228,11 @@ func (f *TMainForm) OnFormCreate(sender vcl.IObject) {
 	// dataRefreshBtn.SetImageIndex(imgLightning)
 	dataRefreshBtn.SetOnClick(func(sender vcl.IObject) { f.RefreshCurrentItem() })
 
+	dataInsertBtn := vcl.NewToolButton(dataButtonBar)
+	dataInsertBtn.SetParent(dataButtonBar)
+	dataInsertBtn.SetCaption("Insert")
+	dataInsertBtn.SetOnClick(f.OnDataInsertClick)
+
 	f.contentBox = vcl.NewStringGrid(dataTab)
 	f.contentBox.SetParent(dataTab)
 	f.contentBox.BorderSpacing().SetLeft(MY_SPACING)
@@ -233,6 +240,7 @@ func (f *TMainForm) OnFormCreate(sender vcl.IObject) {
 	f.contentBox.BorderSpacing().SetBottom(MY_SPACING)
 	f.contentBox.SetAlign(types.AlClient) // fill remaining space
 	f.contentBox.SetOptions(f.contentBox.Options().Include(types.GoThumbTracking, types.GoColSizing, types.GoDblClickAutoSize))
+	f.contentBox.SetOnPrepareCanvas(f.OnDataPrepareCanvas)
 	f.contentBox.SetDefaultColWidth(MY_WIDTH)
 	vcl_stringgrid_clear(f.contentBox)
 
@@ -521,6 +529,39 @@ func (f *TMainForm) OnNavContextRefresh(item *vcl.TTreeNode, ndata *navData) {
 	item.SetExpanded(isExpanded)
 }
 
+func (f *TMainForm) OnDataPrepareCanvas(sender vcl.IObject, aCol, aRow int32, aState types.TGridDrawState) {
+	if len(f.insertRows) == 0 {
+		return // fast-path
+	}
+
+	isInsertRow := false
+	for _, rr := range f.insertRows {
+		if rr == aRow {
+			isInsertRow = true
+			break
+		}
+	}
+
+	if isInsertRow {
+		/*sender.(*vcl.TStringGrid)*/
+		f.contentBox.Canvas().Brush().SetColor(colors.ClYellow)
+	}
+}
+
+func (f *TMainForm) OnDataInsertClick(sender vcl.IObject) {
+	if !f.contentBox.Enabled() {
+		return // Not an active data view
+	}
+
+	rpos := f.contentBox.RowCount()
+	f.contentBox.SetRowCount(rpos + 1)
+
+	f.insertRows = append(f.insertRows, rpos)
+
+	// Scroll to bottom
+	f.contentBox.SetTopRow(rpos)
+}
+
 func (f *TMainForm) OnNavContextClose(sender vcl.IObject) {
 	curItem := f.Buckets.Selected()
 	if curItem == nil {
@@ -572,6 +613,7 @@ func (f *TMainForm) OnNavChange(sender vcl.IObject, node *vcl.TTreeNode) {
 	}
 
 	// Reset some controls that the render function is expected to populate
+	f.insertRows = nil
 	f.propertiesBox.Clear()
 	vcl_stringgrid_clear(f.contentBox)