ggplot2 - Plot timeline in R as single labeled bar and with dates at the x-axis labels

Question

I want to create a nice timeline plot using the timeline package in R, but I am not sure how to fix these issues I am having with it. One is that these bars stack upwards, but I'd like them to be on the same level. The y-axis should be left out. The x-axis should use the labels from the StartLabel column. How do I get it there?

Here is the code and data:

require(data.table)
require(timeline)

setsTimeline <- data.table(Set=c("x","y","z","x","y","z","x","y","z","x","y","z","x"),
       StartDate=c(1380708900,1402963200,1420070400,1421280000,1410912000,1396310400,1397520000,1418860800,1404172800,1405382400,1395100800,1412121600,1413331200),
       EndDate=  c(1395099900,1404171900,1421279100,1430985600,1412120700,1397519100,1402962300,1420069500,1405381500,1410911100,1396309500,1413330300,1418859900))

setsTimeline[,StartLabel:=as.POSIXct(StartDate,tz="UTC",origin="1970-01-01")]
setsTimeline[,Group:=c("Timeline")]
setkey(setsTimeline,StartDate)

timeline(setsTimeline,label.col="Set",start.col="StartDate",end.col="EndDate",group.col="Group")

Something like this is what I'd like to see: http://timelyportfolio.github.io/rCharts_time_series/assets/fig/unnamed-chunk-3.png

But now it looks like this:

Edit: So maybe this is a lost cause, because this package is just not finished yet. I did manage to get the graph unstacked. It appears one has to define a group variable. But still I am unable to figure out how to change the labels and add a legend. It appears this plot does not respond to the usual plot functions. I edited the code above and here is the current graph:

Answer 1

So apparently the thing I wanted to do is even possible with just ggplot2, so I am wondering why someone is even bothering creating a new package for it. I spent a few more hours trying to find the right options and stuff but here goes:

require(data.table)
require(ggplot2)
require(grid)

setsTimeline <- data.table(Set=c("x","y","z","x","y","z","x","y","z","x","y","z","x"),
       StartDate=c(1380708900,1402963200,1420070400,1421280000,1410912000,1396310400,1397520000,1418860800,1404172800,1405382400,1395100800,1412121600,1413331200),
   EndDate=  c(1395099900,1404171900,1421279100,1430985600,1412120700,1397519100,1402962300,1420069500,1405381500,1410911100,1396309500,1413330300,1418859900))

setsTimeline[,StartLabel:=as.POSIXct(StartDate,tz="UTC",origin="1970-01-01")]

breaks <- c(1380708900,1395100800,1402963200,1410912000,1418860800,1430985600)
labels <- as.POSIXct(breaks,tz="UTC",origin="1970-01-01")

ggplot(setsTimeline, aes(colour=Set)) + 
  geom_segment(aes(x=StartDate, xend=EndDate, y="group", yend="group"), size=10) +
  theme(panel.grid.major = element_blank(), 
    panel.grid.minor = element_blank(), 
    panel.background = element_blank(),
    aspect.ratio=5e-02, 
    axis.text.x = element_text(colour='black', angle = 45, size = 16, hjust = 1, vjust = 1),
    legend.text = element_text(colour='black', size = 16),
    legend.title = element_text(colour='black', size = 0),
    legend.position = 'top',
    plot.title = element_text(colour='black', size = 18),
    panel.margin = unit(1, "cm")) +
  xlab(NULL) + 
  ylab(NULL) +
  ggtitle("Data timeline with marked sets") +
  coord_cartesian(xlim = c(1380708900,1430985600), ylim = NULL) +
  scale_x_continuous(breaks=breaks,labels=labels)

results in:

if someone comes by who knows how to get rid of the y-axis and how to get the first x-axis label to remain within the plot area without having to move/turn it, please help me out. I tried plot.margin and panel.margin, but one did nothing and the other kept erroring out.

it is now way past my bedtime and I have a presentation to give tomorrow...