Multiple ggplots in for loop

I produced multiple plots using the following code:

set.seed(12345)
a <- data.frame(Glabel=LETTERS[1:7],   A=rnorm(7, mean = 0, sd = 1),  B=rnorm(7, mean = 0, sd = 1),  C=rnorm(7, mean = 0, sd = 1))
T <- data.frame(Tlabel=LETTERS[11:20], A=rnorm(10, mean = 0, sd = 1), B=rnorm(10, mean = 0, sd = 1), C=rnorm(10, mean = 0, sd = 1))


 for(i in 2:(ncol(a)-1))
  {
    for(j in (i+1):ncol(a))
    {
      r <- 0.08
      win.graph(width=10, height=10, pointsize=12)
      plot(a[, i],a[, j], pch=19, cex=1, panel.first=grid(col="gray", lty="dotted"))
      points(T[, i],T[, j],pch=19, col="white", cex=1)
      text(a[, i],a[, j], rownames(a), cex=1,col="black", pos=1)
      text(T[, i],T[, j], rownames(T), cex=1,col="blue",  pos=1)
      arrows(x0=0, y0=0, x1=T[, i], y1=T[, j], length=0.1,col=2,lty=1)
    }
  }

Using win.graph I can maintain all plots in base. But I'd like to have my plot in ggplot2. Following is my code ggplot2.

library(ggplot2)
 for(i in 2:(ncol(a)-1))
  {
    for(j in (i+1):ncol(a))
    {
      r <- 0.08
      p <- ggplot(data=a, mapping=aes(x=a[, i], y=a[, j])) + geom_point() + theme_bw()
      p <- p + geom_text(data=a, mapping=aes(x=a[, i], y=a[, j], label=Glabel),
                     size=3, vjust=1.35, colour="black")
      p <- p + geom_segment(data = T, aes(xend = T[ ,i], yend=T[ ,j]),
                        x=0, y=0, colour="black开发者_如何转开发",
                        arrow=arrow(angle=25, length=unit(0.25, "cm")))
      p <- p + geom_text(data=T, aes(x=T[ ,i], y=T[ ,j], label=Tlabel), size=3, vjust=0, colour="red")
      print(p)
    }
  }

The above code gives me the last graph only. I wonder how can I get all possible graphs in ggplot2. Thanks

From @baptiste's comment:

library(ggplot2)
for(i in 2:(ncol(a)-1))
{
 for(j in (i+1):ncol(a))
 {
  r <- 0.08
  p <- ggplot(data=a, mapping=aes(x=a[, i], y=a[, j])) + geom_point() + theme_bw()
  p <- p + geom_text(data=a, mapping=aes(x=a[, i], y=a[, j], label=Glabel),
                 size=3, vjust=1.35, colour="black")
  p <- p + geom_segment(data = T, aes(xend = T[ ,i], yend=T[ ,j]),
                    x=0, y=0, colour="black",
                    arrow=arrow(angle=25, length=unit(0.25, "cm")))
  p <- p + geom_text(data=T, aes(x=T[ ,i], y=T[ ,j], label=Tlabel), size=3, vjust=0, colour="red")
dev.new()
  print(p)
}


 }