Activity Monitor

This example is a showcase, not a beginner tutorial.

Its value is not that you should copy it directly into your own product. Its value is that it puts several Ansiq capabilities into one realistic terminal application:

• fixed shell layout
• tab switching
• process table rendering
• periodic sampling
• bottom summary panels

Run it

cargo run -p ansiq-examples --example activity_monitor

The real activity_monitor example running in a terminal.

What this example is good for

If you already understand a small Ansiq app, this example is useful because it shows:

• how to keep a shell stable while data refreshes
• how a realtime snapshot can feed the UI
• how Tabs + Table + summary panels cooperate
• why system sampling should live in a service/sampler layer instead of inside rendering code

Widgets to study alongside this example

• Shell
• StatusBar
• Tabs
• Table
• Block
• Paragraph

What to observe at runtime

1. Tabs switch views, not the whole application model

The five tabs are different views over one monitoring shell. They are not five separate applications.

2. The process table is the primary dynamic region

This is a good example of why a fixed shell matters:

• the top structure stays stable
• the bottom summary does not get pushed out
• most dynamic change is concentrated in the center content region

3. The bottom summary is a second live view

It is not just footer copy. It is another state-driven panel that changes together with the table and the active tab.

How to read the code

Do not start with the table cells.

A better order is:

1. inspect the snapshot model
2. inspect how the sampler builds ActivitySnapshot
3. inspect how the scenario tracks the active tab and selected process
4. only then inspect the UI tree

This makes it easier to understand that the example is mainly about runtime + state + shell, not about a single widget.

What this example intentionally does not guarantee

The first version does not try to match macOS Activity Monitor field-for-field.

For example:

• Energy is still approximate
• Network depends on system command availability
• some fields degrade under restricted permissions

That is a conscious boundary. The example exists to show how Ansiq can host a real system-data-driven TUI, not to perfectly clone Apple’s product.

How this maps back to the Guide

This example becomes much easier to understand after:

1. Layout and Rendering
2. State, Focus, Input
3. Streaming and Async Tasks
4. Shell
5. Table