Add default unknown widget

Let people know if they are doing something wrong

unknown/widget.go

@@ -0,0 +1,31 @@
+package unknown
+
+import (
+	"fmt"
+
+	"github.com/rivo/tview"
+	"github.com/wtfutil/wtf/wtf"
+)
+
+type Widget struct {
+	wtf.TextWidget
+}
+
+func NewWidget(app *tview.Application, name string) *Widget {
+	widget := Widget{
+		TextWidget: wtf.NewTextWidget(app, name, name, false),
+	}
+
+	return &widget
+}
+
+/* -------------------- Exported Functions -------------------- */
+
+func (widget *Widget) Refresh() {
+
+	widget.View.SetTitle(widget.ContextualTitle(fmt.Sprintf("%s", widget.Name)))
+	widget.View.Clear()
+
+	content := fmt.Sprintf("Widget %s does not exist", widget.Name)
+	widget.View.SetText(content)
+}