`hjust = 0` does what you want. *hjust* stands for *horizontal justification*, 0 will be left-justified, 0.5 will be centered, and 1 will be right-justified. 

    qplot(mtcars$mpg) +
        annotate(geom = &quot;text&quot;, x = 30, y = 3,
                 label = &quot;Some text\nSome more text&quot;,
                 hjust = 0)

See also `vjust` for vertical justification.

In `ggplot2`, these arguments are present any time text preferences are set. They work for `annotate`, `geom_text`, or in `element_text` when adjusting theme options. 

If you look at `?geom_text`, you can find text string options: `&quot;left&quot;`, `&quot;middle&quot;`, or `&quot;right&quot;`, (for `hjust`), `&quot;top&quot;`, `&quot;center&quot;`, `&quot;bottom&quot;` for `vjust`, and for either `&quot;inward&quot;` and `&quot;outward&quot;` which will always adjust in toward or out away from the center.

---

This behavior is similar in many `base` graphics functions, such as the `adj` argument for `par`, used by `text()`, `mtext()`, and `title()`, which can be vector of length 2 for the horizontal and vertical justificatons. Also the `hadj` and `padj` arguments to `axis()` for justifications *h*orizontal to and *p*erpendicular to the axis.

While compiling i get the error `Error:compileSdkVersion android-21 requires compiling with JDK 7`, saying that a newer version of JDK is required.

I&#39;m running on OS X Yosemite with Android Studio v0.8.14

Things I checked : 

1. Java version :

`java version &quot;1.8.0_25&quot;
Java(TM) SE Runtime Environment (build 1.8.0_25-b17)
Java HotSpot(TM) 64-Bit Server VM (build 25.25-b02, mixed mode)`
 
2. Inside the JavaVirtualMachine folder I can see only `1.6.0.jdk` folder, I cannot find any other folder.

3. Tried reinstalling JDk 8 and 7!

I&#39;m unable to find the folder location of jvm 1.8, any idea how I can fix there.

Error:compileSdkVersion android-21 requires compiling with JDK 7

I&#39;m writing a piece of code where I want to time how long a button was held down. To do that I recorded an `NSDate()` when the button was pressed, and tried using the `timeIntervalSinceDate` function when the button was released. That seems to work but I can&#39;t find any way to print the result or switch it to an integer.

    var timeAtPress = NSDate() 

    @IBAction func pressed(sender: AnyObject) {
        println(&quot;pressed&quot;)
        timeAtPress = NSDate()
    }
    
    @IBAction func released(sender: AnyObject) {
        println(&quot;released&quot;)
        var elapsedTime = NSDate.timeIntervalSinceDate(timeAtPress)
        duration = ???
    }

I&#39;ve seen a few similar questions, but I don&#39;t know C so I had a hard time understanding the answers given. If there is a more efficient way to find out how long the button was held down I&#39;m open to suggestions. Thanks in advance.

Find difference in seconds between NSDates as integer using Swift

My example is:
```r
qplot(mtcars$mpg) + 
  annotate(geom = &quot;text&quot;, x = 30, y = 3, label = &quot;Some text\nSome more text&quot;)
```
How do I get the text here to be left aligned? So that the &#39;Some&#39;s line up with each other.

How to left align text in annotate from ggplot2

My example is:
<pre><code class="hljs language-ini">qplot(mtcars$mpg) + 
 annotate(geom = "text", x = 30, y = 3, label = "Some text\nSome more text")
</code></pre>
How do I get the text here to be left aligned? So that the 'Some's line up with each other.

I&#39;m new using dplyr,
I need to calculate the distinct values in a group. Here&#39;s a table example:

    data=data.frame(aa=c(1,2,3,4,NA), bb=c(&#39;a&#39;, &#39;b&#39;, &#39;a&#39;, &#39;c&#39;, &#39;c&#39;))

I know I can do things like:

    by_bb&lt;-group_by(data, bb, add = TRUE)
    summarise(by_bb, mean(aa, na.rm=TRUE), max(aa), sum(!is.na(aa)), length(aa))

But if I want the count of unique elements?

I can do:

      &gt; summarise(by_bb,length(unique(unlist(aa))))

      bb length(unique(unlist(aa)))
    1  a                          2
    2  b                          1
    3  c                          2


and if I want to exclude NAs I cand do:

    &gt; summarise(by_bb,length(unique(unlist(aa[!is.na(aa)]))))

      bb length(unique(unlist(aa[!is.na(aa)])))
    1  a                                      2
    2  b                                      1
    3  c                                      1

But it&#39;s a **little unreadable for me**. Is there a better way to do this kind of summarization?

Get dplyr count of distinct in a readable way

**UPDATE July 2020:**

`dplyr` 1.0 has changed pretty much everything about this question as well as all of the answers. See the `dplyr` programming vignette here:

https://cran.r-project.org/web/packages/dplyr/vignettes/programming.html

The new way to refer to columns when their identifier is stored as a character vector is to use the `.data` pronoun from `rlang`, and then subset as you would in base R. 

```
library(dplyr)

key &lt;- &quot;v3&quot;
val &lt;- &quot;v2&quot;
drp &lt;- &quot;v1&quot;

df &lt;- tibble(v1 = 1:5, v2 = 6:10, v3 = c(rep(&quot;A&quot;, 3), rep(&quot;B&quot;, 2)))

df %&gt;% 
    select(-matches(drp)) %&gt;% 
    group_by(.data[[key]]) %&gt;% 
    summarise(total = sum(.data[[val]], na.rm = TRUE))

#&gt; `summarise()` ungrouping output (override with `.groups` argument)
#&gt; # A tibble: 2 x 2
#&gt;   v3    total
#&gt;   &lt;chr&gt; &lt;int&gt;
#&gt; 1 A        21
#&gt; 2 B        19

```

If your code is in a package function, you can `@importFrom rlang .data` to avoid R check notes about undefined globals. 

**ORIGINAL QUESTION:**

I want to refer to an unknown column name inside a `summarise`. The standard evaluation functions introduced in `dplyr 0.3` allow column names to be referenced using variables, but this doesn&#39;t appear to work when you call a `base` R function within e.g. a `summarise`. 

    library(dplyr)
     
    key &lt;- &quot;v3&quot;
    val &lt;- &quot;v2&quot;
    drp &lt;- &quot;v1&quot;
     
    df &lt;- data_frame(v1 = 1:5, v2 = 6:10, v3 = c(rep(&quot;A&quot;, 3), rep(&quot;B&quot;, 2)))
 
The df looks like this:

    &gt; df
    Source: local data frame [5 x 3]
    
      v1 v2 v3
    1  1  6  A
    2  2  7  A
    3  3  8  A
    4  4  9  B
    5  5 10  B

I want to drop v1, group by v3, and sum v2 for each group:

    df %&gt;% select(-matches(drp)) %&gt;% group_by_(key) %&gt;% summarise_(sum(val, na.rm = TRUE))

    Error in sum(val, na.rm = TRUE) : invalid &#39;type&#39; (character) of argument

The NSE version of `select()` works fine, since it can match a character string. The SE version of `group_by()` works fine, since it can now accept variables as arguments and evaluate them. However, I haven&#39;t found a way to achieve similar results when using base R functions inside `dplyr` functions. 

Things that don&#39;t work:

    df %&gt;% group_by_(key) %&gt;% summarise_(sum(get(val), na.rm = TRUE))
    Error in get(val) : object &#39;v2&#39; not found

    df %&gt;% group_by_(key) %&gt;% summarise_(sum(eval(as.symbol(val)), na.rm = TRUE))
    Error in eval(expr, envir, enclos) : object &#39;v2&#39; not found

I&#39;ve checked out [several][1] [related][2] [questions][3], but none of the proposed solutions have worked for me so far. 


  [1]: https://stackoverflow.com/questions/21208801/group-by-multiple-columns-in-dplyr-using-string-vector-input
  [2]: https://stackoverflow.com/questions/21390141/specify-dplyr-column-names
  [3]: https://stackoverflow.com/questions/26492280/non-standard-evaluation-nse-in-dplyrs-filter-pulling-data-from-mysql

standard evaluation in dplyr: summarise a variable given as a character string

I&#39;m trying to make shiny apps available to my coworkers without them having to run or even have R installed.

So I read [this webpage](https://shiny.rstudio.com/tutorial/written-tutorial/lesson7/)
and found this sentence:

&gt; If you are familiar with web hosting or have access to an IT
&gt; department, you can host your Shiny apps yourself.

under the &#39;*Share as a web page*&#39;-section.

How can I do this?

The problem is that my company is bound to certain restrictions regarding web hosting and security and so on, and will not (for now) pay for a shiny-server-pro. 

But the sentence above gives me hope to set up something ourselves to convince them.

Hosting and setting up own shiny apps without shiny server

    string = c(&quot;apple&quot;, &quot;apples&quot;, &quot;applez&quot;)
    grep(&quot;apple&quot;, string)

This would give me the index for all three elements in `string`. But I want an exact match on the word &quot;apple&quot; (i.e I just want `grep()` to return index 1).  

How to use grep()/gsub() to find exact match

I feel like this should be obvious...   all I&#39;m trying to do is to remove the x-axis from the bottom of my graph and add it to the top.

Here is a reproducible example.    Data plus code to make the following graph:

    library(reshape2)
    library(ggplot2)
    
    data(mtcars)
    dat &lt;- with(mtcars, data.frame(mpg, cyl, disp, hp, wt, gear))
    cor.matrix &lt;- round(cor(dat, use = &quot;pairwise.complete.obs&quot;, method = &quot;spearman&quot;), digits = 2)
    diag(cor.matrix)&lt;-NA
    
    cor.dat &lt;- melt(cor.matrix)
    cor.dat &lt;- data.frame(cor.dat)
    cor.dat &lt;- cor.dat[complete.cases(cor.dat),]
    
    
    ggplot(cor.dat, aes(Var2, Var1, fill = value)) + 
      geom_tile(colour=&quot;gray90&quot;, size=1.5, stat=&quot;identity&quot;) + 
      geom_text(data=cor.dat, aes(Var2, Var1, label = value), color=&quot;black&quot;, size=rel(4.5)) +
      scale_fill_gradient(low = &quot;white&quot;, high = &quot;dodgerblue&quot;, space = &quot;Lab&quot;, na.value = &quot;gray90&quot;, guide = &quot;colourbar&quot;) +
      scale_x_discrete(expand = c(0, 0)) +
      scale_y_discrete(expand = c(0, 0)) +
      xlab(&quot;&quot;) + 
      ylab(&quot;&quot;) +
      theme(panel.grid.major = element_blank(),
            panel.grid.minor = element_blank(),
            panel.border = element_rect(fill=NA,color=&quot;gray90&quot;, size=0.5, linetype=&quot;solid&quot;),
            axis.line = element_blank(),
            axis.ticks = element_blank(),
            panel.background = element_rect(fill=&quot;gray90&quot;),
            plot.background = element_rect(fill=&quot;gray90&quot;),
            legend.position = &quot;none&quot;, 
            axis.text = element_text(color=&quot;black&quot;, size=14) )



![enter image description here][1]


But what I&#39;m trying to produce is-  it seems like this should be obvious (e.g. it&#39;s very easy to do in base-R) , but I haven&#39;t managed to find what I&#39;m looking for in ggplot2.

![enter image description here][2]


  [1]: http://i.stack.imgur.com/Nscqv.png
  [2]: http://i.stack.imgur.com/IIW0g.png

Putting x-axis at top of ggplot2 chart

With this data frame (&quot;df&quot;):

    year pollution
    1 1999 346.82000
    2 2002 134.30882
    3 2005 130.43038
    4 2008  88.27546


I try to create a line chart like this:

      plot5 &lt;- ggplot(df, aes(year, pollution)) +
               geom_point() +
               geom_line() +
               labs(x = &quot;Year&quot;, y = &quot;Particulate matter emissions (tons)&quot;, title = &quot;Motor vehicle emissions in Baltimore&quot;)


The error I get is:

&gt; geom_path: Each group consist of only one observation. Do you need to
&gt; adjust the group aesthetic?

The chart appears as a scatter plot even though I want a line chart. I tried to replace `geom_line()` with `geom_line(aes(group = year))` but that didn&#39;t work. 

In an answer I was told to convert year to a factor variable. I did and the problem persists. This is the output of `str(df)` and `dput(df)`:

    &#39;data.frame&#39;:	4 obs. of  2 variables:
     $ year     : num  1 2 3 4
     $ pollution: num [1:4(1d)] 346.8 134.3 130.4 88.3
      ..- attr(*, &quot;dimnames&quot;)=List of 1
      .. ..$ : chr  &quot;1999&quot; &quot;2002&quot; &quot;2005&quot; &quot;2008&quot;

    structure(list(year = c(1, 2, 3, 4), pollution = structure(c(346.82, 
    134.308821199349, 130.430379885892, 88.275457392443), .Dim = 4L, .Dimnames = list(
        c(&quot;1999&quot;, &quot;2002&quot;, &quot;2005&quot;, &quot;2008&quot;)))), .Names = c(&quot;year&quot;, 
    &quot;pollution&quot;), row.names = c(NA, -4L), class = &quot;data.frame&quot;)



ggplot2 line chart gives &quot;geom_path: Each group consist of only one observation. Do you need to adjust the group aesthetic?&quot;

    library(ggplot2)
    library(scales)
    library(reshape2)  

    Rdates &lt;- c(&quot;2007-01-31&quot;,&quot;2007-02-28&quot;,&quot;2007-03-30&quot;,&quot;2007-04-30&quot;,&quot;2007-05-31&quot;,&quot;2007-06-29&quot;,&quot;2007-07-31&quot;,&quot;2007-08-31&quot;,&quot;2007-09-28&quot;,&quot;2007-10-31&quot;)
    Rdates &lt;- as.Date(Rdates)
    Cnames &lt;- c(&quot;Column 1 Really Long&quot;,&quot;Column 2 Really Long&quot;,&quot;Column 3 Really Long&quot;,&quot;Column 4 Really Long&quot;,&quot;Column 5 Really Long&quot;,&quot;Column 6 Really Long&quot;,&quot;Column 7 Really Long&quot;,&quot;Column 8 Really Long&quot;,&quot;Column 9 Really Long&quot;,&quot;Column 10 Really Long&quot;)
    MAINDF &lt;- data.frame(replicate(10,runif(10,-0.03,0.03)))
    rownames(MAINDF) &lt;- Rdates
    colnames(MAINDF) &lt;- Cnames
    CUSTOMpalette &lt;- c(&quot;#1a2ffa&quot;, &quot;#0d177d&quot;, &quot;#1a9ffa&quot;, &quot;#fa751a&quot;, &quot;#4b8e12&quot;, &quot;#6fd21b&quot;, &quot;#fae51a&quot;, &quot;#c3b104&quot;, &quot;#f5df05&quot;, &quot;#dcc805&quot;)
    MAINDF[,&quot;dates&quot;] &lt;- Rdates
    
    MAINDF &lt;- melt(MAINDF,id.vars=&quot;dates&quot;)
    
    gg &lt;- ggplot(MAINDF, aes(x = dates, y = value, fill = variable))
    gg &lt;- gg + geom_bar(stat = &quot;identity&quot;)
    gg &lt;- gg + scale_x_date(breaks = &quot;3 months&quot;, labels=date_format(&quot;%b%y&quot;),limits=c(min(as.Date(MAINDF$dates)),max(as.Date(MAINDF$dates))))
    gg &lt;- gg + theme(
      axis.text.x= element_text(color=&quot;black&quot;,angle=45, size=10, vjust=0.5),
      axis.text.y= element_text(color=&quot;black&quot;, size=12, vjust=0.5),
      axis.title.y = element_text(color=&quot;black&quot;,size=12, vjust=0.5),
      plot.title = element_text(color=&quot;black&quot;,face=&quot;bold&quot;,size=14, hjust=0.5,vjust=1),
      panel.background = element_blank(),
      panel.border = element_rect(linetype = &quot;solid&quot;, colour = &quot;black&quot;,fill=NA),
      legend.position=&quot;bottom&quot;,
      legend.title = element_blank(),
      legend.key = element_rect(fill=&quot;white&quot;), legend.background = element_rect(fill=NA)
    )
    gg &lt;- gg + xlab(&quot;&quot;) + ylab(&quot;Monthly Returns&quot;) 
    gg &lt;- gg + ggtitle(&quot;Contribution by Strategy&quot;)
    gg &lt;- gg + scale_y_continuous(labels = percent_format())
    gg &lt;- gg + scale_fill_manual(values=CUSTOMpalette)
    gg

Currently have a ggplot2 stacked bar graph setup. Everything works properly now except I am having an issue with the legend. I have put it on the bottom but there are 10 items so some are cutoff (doesnt fit). I tried  `guides(fill=guide_legend(nrow=2))` but this puts the labels in a different order (I want to get the first 5 across then the last 5 below. Any suggestions?

Legend on bottom, two rows wrapped in ggplot2 in r

How can we change y axis to percent like the figure? I can change y axis range but I can&#39;t make it to percent.
![enter image description here][1]


  [1]: http://i.stack.imgur.com/wuK3a.jpg

How can I change the Y-axis figures into percentages in a barplot?

I was asked by a student if it was possible to recreate a plot similar to the one below using R:

![enter image description here][1]   This is from  [this paper....][2]

This sort of stuff isn&#39;t my specialty, but using the following code I was able to create 95% CI ellipses and to plot them with `geom_polygon()`.  I filled the images with images I grabbed from the phylopic library using the `rphylopic` package.

    #example data/ellipses
    set.seed(101)
    n &lt;- 1000
    x1 &lt;- rnorm(n, mean=2)
    y1 &lt;- 1.75 + 0.4*x1 + rnorm(n)
    df &lt;- data.frame(x=x1, y=y1, group=&quot;A&quot;)
    x2 &lt;- rnorm(n, mean=8)
    y2 &lt;- 0.7*x2 + 2 + rnorm(n)
    df &lt;- rbind(df, data.frame(x=x2, y=y2, group=&quot;B&quot;))
    x3 &lt;- rnorm(n, mean=6)
    y3 &lt;- x3 - 5 - rnorm(n)
    df &lt;- rbind(df, data.frame(x=x3, y=y3, group=&quot;C&quot;))
    
 
    #calculating ellipses
    library(ellipse)
    df_ell &lt;- data.frame()
    for(g in levels(df$group)){
      df_ell &lt;- rbind(df_ell, cbind(as.data.frame(with(df[df$group==g,], ellipse(cor(x, y), 
                                                                                 scale=c(sd(x),sd(y)), 
                                                                                 centre=c(mean(x),mean(y))))),group=g))
    }
    #drawing
    library(ggplot2)
    p &lt;- ggplot(data=df, aes(x=x, y=y,colour=group)) + 
      #geom_point(size=1.5, alpha=.6) +
      geom_polygon(data=df_ell, aes(x=x, y=y,colour=group, fill=group), alpha=0.1, size=1, linetype=1)
    
     
    ### get center points of ellipses
    library(dplyr)
    ell_center &lt;- df_ell %&gt;% group_by(group) %&gt;% summarise(x=mean(x), y=mean(y))
    
    ### animal images
    library(rphylopic)
    lion &lt;- get_image(&quot;e2015ba3-4f7e-4950-9bde-005e8678d77b&quot;, size = &quot;512&quot;)[[1]]
    mouse &lt;- get_image(&quot;6b2b98f6-f879-445f-9ac2-2c2563157025&quot;, size=&quot;512&quot;)[[1]] 
    bug &lt;- get_image(&quot;136edfe2-2731-4acd-9a05-907262dd1311&quot;, size=&quot;512&quot;)[[1]]
    
    ### overlay images on center points
    p + add_phylopic(lion, alpha=0.9, x=ell_center[[1,2]], y=ell_center[[1,3]], ysize=2, color=&quot;firebrick1&quot;)  + 
        add_phylopic(mouse, alpha=1, x=ell_center[[2,2]], y=ell_center[[2,3]], ysize=2, color=&quot;darkgreen&quot;) +
        add_phylopic(bug, alpha=0.9, x=ell_center[[3,2]], y=ell_center[[3,3]], ysize=2, color=&quot;mediumblue&quot;) + 
      theme_bw()


Which gives the following:

![enter image description here][3]

This is ok, but what I&#39;d really like to do is to add an image directly to the &#39;fill&#39; command of geom_polygon.   Is this possible ?  


  [1]: http://i.stack.imgur.com/j0074.png
  [2]: http://www.nature.com/nature/journal/v472/n7341/full/nature09904.html?WT.ec_id=NATURE-20110407
  [3]: http://i.stack.imgur.com/AU8pi.png

Adding custom image to geom_polygon fill in ggplot

I have not encountered this before, and I am having a very hard time trying to find the solution. When having a column equal to medium in bootstrap like so:

    &lt;h1 class=&quot;text-center&quot;&gt;Hello, world!&lt;/h1&gt;
      
      &lt;div class=&quot;container&quot;&gt;
          &lt;div class=&quot;row&quot;&gt;
              &lt;div class=&quot;col-md-12 text-center&quot;&gt;
                  &lt;h1&gt;vicki williams&lt;/h1&gt;
              &lt;/div&gt;
          &lt;/div&gt;
      &lt;/div&gt;
The text-align works fine:
[![enter image description here][1]][1]


But when making the column equal to extra small like so:

     &lt;div class=&quot;container&quot;&gt;
          &lt;div class=&quot;row&quot;&gt;
              &lt;div class=&quot;col-xs-12 text-center&quot;&gt;
                  &lt;h1&gt;vicki williams&lt;/h1&gt;
              &lt;/div&gt;
          &lt;/div&gt;
      &lt;/div&gt;
Then the text-align no longer works:
[![enter image description here][2]][2]


  [1]: https://i.stack.imgur.com/g5WcO.png
  [2]: https://i.stack.imgur.com/HIIkx.png

Is there some bootstrap concept that I am not understanding or is this in fact a error like I think it is. I have never had this issue, as my text always has aligned in the past with xs. Any help would be greatly appreciated.
Here is my complete code:

    &lt;!DOCTYPE html&gt;
    &lt;html lang=&quot;en&quot;&gt;
      &lt;head&gt;
        &lt;!-- Required meta tags --&gt;
        &lt;meta charset=&quot;utf-8&quot;&gt;
        &lt;meta name=&quot;viewport&quot; content=&quot;width=device-width, initial-scale=1, shrink-to-fit=no&quot;&gt;
    
        &lt;!-- Bootstrap CSS --&gt;
        &lt;link rel=&quot;stylesheet&quot; href=&quot;https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/css/bootstrap.min.css&quot; integrity=&quot;sha384-rwoIResjU2yc3z8GV/NPeZWAv56rSmLldC3R/AZzGRnGxQQKnKkoFVhFQhNUwEyJ&quot; crossorigin=&quot;anonymous&quot;&gt;
      &lt;/head&gt;
      &lt;body&gt;
        &lt;h1 class=&quot;text-center&quot;&gt;Hello, world!&lt;/h1&gt;
          
          &lt;div class=&quot;container&quot;&gt;
              &lt;div class=&quot;row&quot;&gt;
                  &lt;div class=&quot;col-xs-12 text-center&quot;&gt;
                      &lt;h1&gt;vicki williams&lt;/h1&gt;
                  &lt;/div&gt;
              &lt;/div&gt;
          &lt;/div&gt;
    
        &lt;!-- jQuery first, then Tether, then Bootstrap JS. --&gt;
        &lt;script src=&quot;https://code.jquery.com/jquery-3.1.1.slim.min.js&quot; integrity=&quot;sha384-A7FZj7v+d/sdmMqp/nOQwliLvUsJfDHW+k9Omg/a/EheAdgtzNs3hpfag6Ed950n&quot; crossorigin=&quot;anonymous&quot;&gt;&lt;/script&gt;
        &lt;script src=&quot;https://cdnjs.cloudflare.com/ajax/libs/tether/1.4.0/js/tether.min.js&quot; integrity=&quot;sha384-DztdAPBWPRXSA/3eYEEUWrWCy7G5KFbe8fFjk5JAIxUYHKkDx6Qin1DkWx51bBrb&quot; crossorigin=&quot;anonymous&quot;&gt;&lt;/script&gt;
        &lt;script src=&quot;https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/js/bootstrap.min.js&quot; integrity=&quot;sha384-vBWWzlZJ8ea9aCX4pEW3rVHjgjt7zpkNpZk+02D9phzyeVkE+jo0ieGizqPLForn&quot; crossorigin=&quot;anonymous&quot;&gt;&lt;/script&gt;
      &lt;/body&gt;
    &lt;/html&gt;

`col-xs-*` not working in Bootstrap 4

In the code below, `textAlign` property doesn&#39;t work. If you remove `DefaultTextStyle` wrapper which is several levels above, `textAlign` starts to work.

Why and how to ensure it is always working?

    import &#39;package:flutter/material.dart&#39;;
    
    void main() =&gt; runApp(new MyApp());
    
    class MyApp extends StatelessWidget {
      // This widget is the root of your application.
      @override
      Widget build(BuildContext context) {
        return new MaterialApp(
          title: &#39;Flutter Demo&#39;,
          theme: new ThemeData(
            primarySwatch: Colors.blue,
          ),
          home: new DefaultTextStyle(style: new TextStyle(fontSize: 10.0), child: new Column(children: &lt;Widget&gt;[
            new Text(&quot;Should be left&quot;, textAlign: TextAlign.left,),
            new Text(&quot;Should be right&quot;, textAlign: TextAlign.right,)
          ],))
        );
      }
    }

***

Both approaches, suggested by Remi apparently don&#39;t work &quot;in the wild&quot;. Here is an example I nested both inside rows and columns. First approach doesn&#39;t do align and second approach makes application just crash:

    import &#39;package:flutter/material.dart&#39;;
    
    void main() =&gt; runApp(new MyApp());
    
    class MyApp extends StatelessWidget {
      // This widget is the root of your application.
      @override
      Widget build(BuildContext context) {
        return new Directionality(textDirection: TextDirection.ltr, child: new DefaultTextStyle(
                style: new TextStyle(fontSize: 10.0, color: Colors.white),
                child: new Column(children: &lt;Widget&gt;[
                  new Row(children: &lt;Widget&gt;[
                    new Container(color: Colors.grey, child: new Column(children: &lt;Widget&gt;[
                      new Align(alignment: Alignment.centerLeft, child: new Text(&quot;left&quot;)),
                      new Align(alignment: Alignment.centerRight, child: new Text(&quot;right&quot;)),
                    ],)),
                    new Container(color: Colors.grey, child: new Column(children: &lt;Widget&gt;[
                      new Align(alignment: Alignment.centerLeft, child: new Text(&quot;left&quot;)),
                      new Align(alignment: Alignment.centerRight, child: new Text(&quot;right&quot;)),
                    ],)),
                  ],),
                  /*new Row(children: &lt;Widget&gt;[
                    new Container(color: Colors.grey, child: new Column(children: &lt;Widget&gt;[
                      new SizedBox(width: double.infinity, child: new Text(&quot;left&quot;, textAlign: TextAlign.left,)),
                      new SizedBox(width: double.infinity, child: new Text(&quot;right&quot;, textAlign: TextAlign.right)),
                    ],)),
                    new Container(color: Colors.grey, child: new Column(children: &lt;Widget&gt;[
                      new SizedBox(width: double.infinity, child: new Text(&quot;left&quot;, textAlign: TextAlign.left)),
                      new SizedBox(width: double.infinity, child: new Text(&quot;right&quot;, textAlign: TextAlign.right)),
                    ],)),
                  ],)*/]
        )));
      }
    }

***

What I get from code is

[![enter image description here][1]][1]

i.e. text is centered, ignoring alignment of `Align` element.


  [1]: https://i.stack.imgur.com/4GyeR.png

Content Type	Original Author	Original Content on Stackoverflow
Question	kennyB	View Question on Stackoverflow
Solution 1 - R	Gregor Thomas	View Answer on Stackoverflow

How to left align text in annotate from ggplot2

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