---
title: "Example 14: Page Break"
output: rmarkdown::html_vignette
vignette: >
  %\VignetteIndexEntry{Example 14: Page Break}
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteEncoding{UTF-8}
---
  
```{r setup, include = FALSE}
knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>"
)
```

### Handle Long Tables with Page Break

Page breaking will occur 
automatically if the table length exceeds the available page length.  But 
page wrapping can also be controlled using the `page_break` parameter on the 
`define()` function.  The `page_break` parameter identifies a column on which 
to break the page.  The page will break every time the page break variable changes.
You can use an existing variable or create a special variable just for the purpose
of controlling the page breaks.  If you create a special variable just for breaking
the page, it is often desirable to make that column invisible.  Here is an 
example:

```{r eval=FALSE, echo=TRUE}  
library(reporter)

# Create temp file name
tmp <- file.path(tempdir(), "example6.pdf")

# Prepare data
dat <- mtcars
dat <- data.frame(vehicle = rownames(dat), dat, 
                  page = c(rep(1, 10), rep(2, 12), rep(3, 10)))
rownames(dat) <- NULL

# View 
dat
#                vehicle  mpg cyl  disp  hp drat    wt  qsec vs am gear carb page
# 1            Mazda RX4 21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4    1
# 2        Mazda RX4 Wag 21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4    1
# 3           Datsun 710 22.8   4 108.0  93 3.85 2.320 18.61  1  1    4    1    1
# 4       Hornet 4 Drive 21.4   6 258.0 110 3.08 3.215 19.44  1  0    3    1    1
# 5    Hornet Sportabout 18.7   8 360.0 175 3.15 3.440 17.02  0  0    3    2    1
# 6              Valiant 18.1   6 225.0 105 2.76 3.460 20.22  1  0    3    1    1
# 7           Duster 360 14.3   8 360.0 245 3.21 3.570 15.84  0  0    3    4    1
# 8            Merc 240D 24.4   4 146.7  62 3.69 3.190 20.00  1  0    4    2    1
# 9             Merc 230 22.8   4 140.8  95 3.92 3.150 22.90  1  0    4    2    1
# 10            Merc 280 19.2   6 167.6 123 3.92 3.440 18.30  1  0    4    4    1
# 11           Merc 280C 17.8   6 167.6 123 3.92 3.440 18.90  1  0    4    4    2
# 12          Merc 450SE 16.4   8 275.8 180 3.07 4.070 17.40  0  0    3    3    2
# 13          Merc 450SL 17.3   8 275.8 180 3.07 3.730 17.60  0  0    3    3    2
# 14         Merc 450SLC 15.2   8 275.8 180 3.07 3.780 18.00  0  0    3    3    2
# 15  Cadillac Fleetwood 10.4   8 472.0 205 2.93 5.250 17.98  0  0    3    4    2
# 16 Lincoln Continental 10.4   8 460.0 215 3.00 5.424 17.82  0  0    3    4    2
# 17   Chrysler Imperial 14.7   8 440.0 230 3.23 5.345 17.42  0  0    3    4    2
# 18            Fiat 128 32.4   4  78.7  66 4.08 2.200 19.47  1  1    4    1    2
# 19         Honda Civic 30.4   4  75.7  52 4.93 1.615 18.52  1  1    4    2    2
# 20      Toyota Corolla 33.9   4  71.1  65 4.22 1.835 19.90  1  1    4    1    2
# 21       Toyota Corona 21.5   4 120.1  97 3.70 2.465 20.01  1  0    3    1    2
# 22    Dodge Challenger 15.5   8 318.0 150 2.76 3.520 16.87  0  0    3    2    2
# 23         AMC Javelin 15.2   8 304.0 150 3.15 3.435 17.30  0  0    3    2    3
# 24          Camaro Z28 13.3   8 350.0 245 3.73 3.840 15.41  0  0    3    4    3
# 25    Pontiac Firebird 19.2   8 400.0 175 3.08 3.845 17.05  0  0    3    2    3
# 26           Fiat X1-9 27.3   4  79.0  66 4.08 1.935 18.90  1  1    4    1    3
# 27       Porsche 914-2 26.0   4 120.3  91 4.43 2.140 16.70  0  1    5    2    3
# 28        Lotus Europa 30.4   4  95.1 113 3.77 1.513 16.90  1  1    5    2    3
# 29      Ford Pantera L 15.8   8 351.0 264 4.22 3.170 14.50  0  1    5    4    3
# 30        Ferrari Dino 19.7   6 145.0 175 3.62 2.770 15.50  0  1    5    6    3
# 31       Maserati Bora 15.0   8 301.0 335 3.54 3.570 14.60  0  1    5    8    3
# 32          Volvo 142E 21.4   4 121.0 109 4.11 2.780 18.60  1  1    4    2    3

# Define table
tbl <- create_table(dat) %>% 
  define(vehicle, label = "Vehicle", width = 2, align = "left") |>
  define(page, page_break = TRUE, visible = FALSE) 


# Create the report
rpt <- create_report(tmp, output_type = "PDF", 
                     font = "Courier", font_size = 12) |>
  titles("Listing 2.0", "MTCARS Data Listing with Page Break") |>
  set_margins(top = 1, bottom = 1) |>
  add_content(tbl) |> 
  page_footer(right = "Page [pg] of [tpg]")

# Write the report
write_report(rpt)

# file.show(tmp)

```
<img src="../man/images/e14a.png" alt="Page break pg 1"/>
<img src="../man/images/e14b.png" alt="Page break pg 2"/>
<img src="../man/images/e14c.png" alt="Page break pg 3"/>

Also note that automatic page breaking can be turned off, if desired.  
See the vignette [Example 18: Report Options](reporter-report_options.html)
for a demonstration.
  
Next: [Example 15: Header and Footer Images](reporter-hfimage.html)

