make it possible to switch between panels

ui/ui.go

@@ -3,6 +3,7 @@ package ui
 import (
 	"strings"
 
+	"git.yetaga.in/alazyreader/library/book"
 	"github.com/gdamore/tcell"
 )
 
@@ -266,6 +267,32 @@ func (l *List) ListMembers() []string {
 	return l.listItems
 }
 
+// A List is a scrollable, pageable list with a selector token.
+type BookDetails struct {
+	x, y     int
+	h, w     int
+	selected int
+	book     book.Book
+}
+
+func NewBookDetails() *BookDetails {
+	return &BookDetails{}
+}
+
+func (l *BookDetails) SetSize(x, y, h, w int) {
+	l.x, l.y, l.h, l.w = x, y, h, w
+}
+
+func (l *BookDetails) Draw(s tcell.Screen) {
+	items := []string{"title", "authors", "isbn-10", "isbn-13"}
+	for i := range items {
+		for j, r := range items[i] {
+			s.SetContent(l.x+j, l.y+i, r, nil, tcell.StyleDefault)
+		}
+		s.SetContent(l.x+len(items[i]), l.y+i, ':', nil, tcell.StyleDefault)
+	}
+}
+
 // PaddedText outputs strings with a space on both sides.
 // Useful for generating headings, footers, etc. Used by Box.
 type PaddedText struct {