Stacked bar chart in ggplot2

Question

I would like plot my data in stacked bar chart. My data is like this

ID,A,B,C
D11,2,2,4
D170,2,0,6
D171,1,5,2
D1,5,0,2
D27,NA,NA,NA
D295,0,6,2

How should I start with.

Answer 1

library('ggplot2')
library('reshape2')
df <- reshape2::melt(df, id.vars = 'ID')  # melt data with ID column
df <- df[!is.na(df$value), ]              # remove NA
ggplot( data = df, aes( x = ID, y = value )) +   
  geom_bar( aes( fill = variable ), stat = 'identity' )

Data:

df <- structure(list(ID = c("D11", "D170", "D171", "D1", "D27", "D295"),
                     A = c(2L, 2L, 1L, 5L, NA, 0L), 
                     B = c(2L, 0L, 5L, 0L, NA, 6L),
                     C = c(4L, 6L, 2L, 2L, NA, 2L)), 
                .Names = c("ID", "A", "B", "C"),
                row.names = c(NA, -6L), class = "data.frame")

Answer 2

In addition to @Sathish's answer. Below is the answer using tidyr and ggplot2

df <- read.table(text = c("
ID  A   B   C
D11 2   2   4
D170    2   0   6
D171    1   5   2
D1  5   0   2
D27 NA  NA  NA
D295    0   6   2"), header = T)

library(tidyr)
library(ggplot2)

df %>% tidyr::gather("var", "value", 2:4) %>% 
  ggplot(., aes(x = ID, y = value))+geom_bar(aes(fill = var ), stat ="identity")