Module crossterm::screen

This module contains all the logic for switching between alternate screen and main screen.

*Nix style applications often utilize an alternate screen buffer, so that they can modify the entire contents of the buffer, without affecting the application that started them. The alternate buffer is exactly the dimensions of the window, without any scrollback region. For an example of this behavior, consider when vim is launched from bash. Vim uses the entirety of the screen to edit the file, then returning to bash leaves the original buffer unchanged.

When using alternate screen there is one thing to keep in mind. To get the functionalities of cursor, color, terminal also working on alternate screen. You need to pass it the same Context as you have passed to the previous three functions, If you don't use the same Context the cursor(), color(), terminal() these modules will be using main screen to write to. So you will see nothing on alternate screen.

When you want to switch to alternate screen there are a couple of things to keep in mind for it to work correctly. First off some code of how to switch to Alternate screen, for more info check the example folder at github

Create alternate screen from Context

// create context.
let context = crossterm::Context::new();
// create instance of Alternatescreen by the given context, this wil also switch to it.
let mut screen = crossterm::AlternateScreen::from(context.clone());
// write to the alternate screen.
write!(screen,  "test");

Create alternate screen from Crossterm:

// create crossterm.
let crossterm = ::crossterm::Crossterm::new();
// create instance of Alternatescreen by the given refrence to crossterm, this wil also switch to it.
let mut screen = crossterm::AlternateScreen::from(&crossterm);
// write to the alternate screen.
write!(screen,  "test");

When using alternate screen there is one thing to keep in mind. To get the functionalities of cursor, color, terminal also working on alternate screen. You need to pass it the same Context as you have passed to the previous three functions, If you don't use the same Context the cursor(), color(), terminal() these modules will be using main screen to write to. So you will see nothing on alternate screen.

Please check the documentation of Context for more info. But basically this Context is a wrapper for a type that provides access to the current screen whether it would be the main screen or alternate screen.

An example of what I mean by that:

// create context.
let context = crossterm::Context::new();

let mut cursor = ::crossterm::cursor::cursor(&context);
cursor.goto(10,10);

// create instance of Alternatescreen by the given refrence to crossterm, this wil also switch to it.
let mut screen = crossterm::AlternateScreen::from(&context);

// now this cursor will be moving on the alternate screen sice it is using the same context as we have passed to the alternatescreen.
cursor.goto(5,4)

To make things easier you can better use Crossterm type for the interactions with alternate screen. This type will manage the Context internally.

So when using this type to switch to AlternateScreen. It will use the Context from the type Crossterm for the AlternateSceen.

 For example:

 // create crossterm instance.
 let crossterm = ::crossterm::Crossterm::new();

 let mut cursor = crossterm.cursor();
 cursor.goto(10,10);

 // create instance of Alternatescreen by the given refrence to crossterm, this wil also switch to it.
 let mut screen = crossterm::AlternateScreen::from(&crossterm);

 // this cursor will be moving on the alternate screen since the current screen is the alternate screen.
 let mut cursor = crossterm.cursor();
 cursor.goto(10,10);

As you can see because we are using Crossterm we won't have to bother about the Context.

Structs

AlternateScreen