Add more powerful bs4col() and bs4row() functions

R/grid.R

@@ -57,4 +57,69 @@ column <- function(width, ..., offset = 0) {
   if (offset > 0) 
     colClass <- paste0(colClass, " offset-sm-", offset)
   shiny::div(class = colClass, ...)
-}
+}
+
+
+#' TBD
+bs4col <- function
+(
+    ...,
+    width = 0,
+    width.xs = NULL, width.md = NULL, width.lg = NULL, width.xl = NULL,
+    offset = NULL,
+    offset.xs = NULL, offset.md = NULL, offset.lg = NULL, offset.xl = NULL,
+    align = NULL, class = c()
+) {
+    colClass = class
+    breakpoints <- c(".xs", "-sm"="", "-md"=".md", "-lg"=".lg", "-xl"=".xl")
+    for (i in seq_along(breakpoints)) {
+        col = paste0("col", names(breakpoints[i]))
+        w = base::get(paste0("width", breakpoints[i]))
+        if (is.null(w)) {
+            if (breakpoints[i] == "") {
+                stop("column width must be 0-12 or 'auto'")
+            }
+        } else if  (w == "auto" || (is.numeric(w) && w >= 1 && w <= 12)) {
+            colClass <- c(colClass, paste0(col, "-", w))
+        } else if (width == 0) {
+            colClass <- c(colClass, col)
+        } else {
+            stop("column width must be 0-12 or 'auto'")
+        }
+        col = paste0("offset", names(breakpoints[i]))
+        w = base::get(paste0("offset", breakpoints[i]))
+        if (is.null(w)) {
+        } else if (is.numeric(w) && w >= 0 && w <= 12) {
+            colClass <- c(colClass, paste0(col, "-", w))
+        } else if (width == 0) {
+            colClass <- c(colClass, col)
+        } else {
+            stop("offset must be 0-12")
+        }
+    }
+    if (!is.null(align)) {
+        if (!align %in% c("start", "center", "end")) {
+            stop("vertical alignment must be start, center or end")
+        }
+        colClass <- c(colClass, paste0("align-self-", align))
+    }
+    shiny::div(class = colClass, ...)
+}
+
+#' TBD
+bs4row <- function(..., align = NULL, justify = NULL, class = c()) {
+    colClass <- c(class, "row")
+    if (!is.null(align)) {
+        if (!align %in% c("start", "center", "end")) {
+            stop("vertical alignment must be start, center or end")
+        }
+        colClass <- c(colClass, paste0("align-self-", align))
+    }
+    if (!is.null(justify)) {
+        if (!align %in% c("start", "center", "end", "around", "between")) {
+            stop("vertical alignment must be start, center, end, around or between")
+        }
+        colClass <- c(colClass, paste0("justify-content-", align))
+    }
+    shiny::div(class = class, ...)
+}