add pagination support for compact view

cursor.go

@@ -7,7 +7,6 @@ import (
 type GridCursor struct {
 	selectedID string // id of currently selected container
 	filtered   Containers
-	containers Containers
 	cSource    ContainerSource
 }
 
@@ -18,83 +17,109 @@ func NewGridCursor() *GridCursor {
 }
 
 func (gc *GridCursor) Len() int             { return len(gc.filtered) }
-func (gc *GridCursor) Selected() *Container { return gc.containers[gc.Idx()] }
+func (gc *GridCursor) Selected() *Container { return gc.filtered[gc.Idx()] }
 
 // Refresh containers from source
 func (gc *GridCursor) RefreshContainers() (lenChanged bool) {
 	oldLen := gc.Len()
-	gc.setContainers(gc.cSource.All())
+
+	// Containers filtered by display bool
+	gc.filtered = Containers{}
+	var cursorVisible bool
+	for _, c := range gc.cSource.All() {
+		if c.display {
+			if c.Id == gc.selectedID {
+				cursorVisible = true
+			}
+			gc.filtered = append(gc.filtered, c)
+		}
+	}
+
 	if oldLen != gc.Len() {
 		lenChanged = true
 	}
+
+	if !cursorVisible {
+		gc.Reset()
+	}
 	if gc.selectedID == "" {
 		gc.Reset()
 	}
 	return lenChanged
 }
 
-func (gc *GridCursor) setContainers(c Containers) {
-	gc.containers = c
-	// Containers filtered by display bool
-	gc.filtered = Containers{}
-	for _, c := range gc.containers {
-		if c.display {
-			gc.filtered = append(gc.filtered, c)
-		}
-	}
-}
-
 // Set an initial cursor position, if possible
 func (gc *GridCursor) Reset() {
-	for _, c := range gc.containers {
+	for _, c := range gc.cSource.All() {
 		c.Widgets.Name.UnHighlight()
 	}
 	if gc.Len() > 0 {
-		gc.selectedID = gc.containers[0].Id
+		gc.selectedID = gc.filtered[0].Id
-		gc.containers[0].Widgets.Name.Highlight()
+		gc.filtered[0].Widgets.Name.Highlight()
 	}
 }
 
 // Return current cursor index
 func (gc *GridCursor) Idx() int {
-	for n, c := range gc.containers {
+	for n, c := range gc.filtered {
 		if c.Id == gc.selectedID {
 			return n
 		}
 	}
+	gc.Reset()
 	return 0
 }
 
+func (gc *GridCursor) ScrollPage() {
+	// skip scroll if no need to page
+	if gc.Len() < cGrid.MaxRows() {
+		cGrid.Offset = 0
+		return
+	}
+
+	idx := gc.Idx()
+
+	// page down
+	if idx >= cGrid.Offset+cGrid.MaxRows() {
+		cGrid.Offset++
+		cGrid.Align()
+	}
+	// page up
+	if idx < cGrid.Offset {
+		cGrid.Offset--
+		cGrid.Align()
+	}
+
+}
+
 func (gc *GridCursor) Up() {
 	idx := gc.Idx()
-	// decrement if possible
+	if idx <= 0 { // already at top
-	if idx <= 0 {
 		return
 	}
-	active := gc.containers[idx]
+	active := gc.filtered[idx]
-	next := gc.containers[idx-1]
+	next := gc.filtered[idx-1]
 
 	active.Widgets.Name.UnHighlight()
 	gc.selectedID = next.Id
 	next.Widgets.Name.Highlight()
 
+	gc.ScrollPage()
 	ui.Render(cGrid)
 }
 
 func (gc *GridCursor) Down() {
 	idx := gc.Idx()
-	// increment if possible
+	if idx >= gc.Len()-1 { // already at bottom
-	if idx >= (gc.Len() - 1) {
 		return
 	}
-	//if idx >= maxRows()-1 {
+	active := gc.filtered[idx]
-	//return
+	next := gc.filtered[idx+1]
-	//}
-	active := gc.containers[idx]
-	next := gc.containers[idx+1]
 
 	active.Widgets.Name.UnHighlight()
 	gc.selectedID = next.Id
 	next.Widgets.Name.Highlight()
+
+	gc.ScrollPage()
 	ui.Render(cGrid)
 }

cwidgets/compact/grid.go

@@ -12,7 +12,7 @@ type CompactGrid struct {
 	X, Y   int
 	Width  int
 	Height int
-	cursorID string
+	Offset int // starting row offset
 }
 
 func NewCompactGrid() *CompactGrid {
@@ -20,29 +20,31 @@ func NewCompactGrid() *CompactGrid {
 }
 
 func (cg *CompactGrid) Align() {
-	// update row y pos recursively
+	// update row ypos, width recursively
 	y := cg.Y
-	for _, r := range cg.Rows {
+	for _, r := range cg.pageRows() {
 		r.SetY(y)
 		y += r.GetHeight()
-	}
-
-	// update row width recursively
-	for _, r := range cg.Rows {
 		r.SetWidth(cg.Width)
 	}
 }
 
-func (cg *CompactGrid) Clear()         { cg.Rows = []ui.GridBufferer{header} }
+func (cg *CompactGrid) Clear()         { cg.Rows = []ui.GridBufferer{} }
 func (cg *CompactGrid) GetHeight() int { return len(cg.Rows) }
 func (cg *CompactGrid) SetX(x int)     { cg.X = x }
 func (cg *CompactGrid) SetY(y int)     { cg.Y = y }
 func (cg *CompactGrid) SetWidth(w int) { cg.Width = w }
 func (cg *CompactGrid) MaxRows() int   { return ui.TermHeight() - header.Height - cg.Y }
 
+func (cg *CompactGrid) pageRows() (rows []ui.GridBufferer) {
+	rows = append(rows, header)
+	rows = append(rows, cg.Rows[cg.Offset:]...)
+	return rows
+}
+
 func (cg *CompactGrid) Buffer() ui.Buffer {
 	buf := ui.NewBuffer()
-	for _, r := range cg.Rows {
+	for _, r := range cg.pageRows() {
 		buf.Merge(r.Buffer())
 	}
 	return buf

grid.go

@@ -19,20 +19,8 @@ func RedrawRows(clr bool) {
 	}
 	cGrid.SetY(y)
 
-	var cursorVisible bool
+	for _, c := range cursor.filtered {
-	max := cGrid.MaxRows()
-	for n, c := range cursor.filtered {
-		if n >= max {
-			break
-		}
 		cGrid.AddRows(c.Widgets)
-		if c.Id == cursor.selectedID {
-			cursorVisible = true
-		}
-	}
-
-	if !cursorVisible {
-		cursor.Reset()
 	}
 
 	if clr {
@@ -136,6 +124,7 @@ func Display() bool {
 
 	ui.Handle("/sys/wnd/resize", func(e ui.Event) {
 		header.Align()
+		cursor.ScrollPage()
 		cGrid.SetWidth(ui.TermWidth())
 		log.Infof("resize: width=%v max-rows=%v", cGrid.Width, cGrid.MaxRows())
 		RedrawRows(true)