Console

Console

One panel for every log line — preview process output, editor logging.* calls, uncaught tracebacks. Searchable, filterable, color-coded by severity.

Opening

Form	How	Notes
Docked panel	F12 or View → Console	Bottom of the workspace. Default home for the log.
Floating window	View → Console (floating)	Pop-out for a second monitor.

Both forms share one buffer — open one mid-run and it replays everything captured so far. Both can be open at once and stay in sync.

What gets captured

Source	Captures	Notes
Preview subprocess	print(), logging.*, tracebacks	Requires Settings → Preview console mode = In-app
Editor (CTkMaker itself)	logging.* at any level	Auto-installed handler on the root logger
Editor	Uncaught Tk callback exceptions + log_error()	Same path as logging.*
Editor print()	Not captured	Use logging.info(...) instead — see Event Handlers

The preview's logging is pre-configured by the in-app runner — every level flows out as LEVEL | logger.name | message. You don't need logging.basicConfig() in your behavior file.

Toolbar (left → right)

Element	Action
Copy	Copy selection (or whole buffer when nothing selected)
Search / Ctrl+F	Slide-in find bar; live highlight; Enter cycles
Info / Warn / Error / Debug	Severity filter checkboxes — instant elide, no rebuild
N badge	Live counter next to Info / Warn / Error — shows full count even when the filter hides the lines
Clear	Wipe buffer + counters (both editor and preview sides)
Stop	Terminate every running preview process
Auto-clear on preview	Wipe preview lines on each preview start — editor lines survive
Lock scroll	Stop auto-scrolling on new output; auto-toggles when you scroll up
× (docked only)	Close the docked panel

Severity colors

Level	Visual
DEBUG	Dim gray
INFO	Default foreground
WARNING	Amber
ERROR	Red
CRITICAL	Bold red

Plain stderr lines (no recognized level prefix) inherit the ERROR color but do not increment the error counter — otherwise a multi-line traceback would inflate the badge unrealistically.

Line format

[14:32:01.74] [E] LEVEL | logger.name | message

Part	Meaning
[14:32:01.74]	Centisecond timestamp. Omitted on continuation lines (see below).
[E]	Editor-source marker. Preview lines omit it.
LEVEL | logger.name | message	Standard logging format — parsed for the level color.

Multi-line grouping

When two stdout / stderr lines arrive within 500 ms on the same stream (typical multi-line traceback), the second one drops its [ts] prefix. Event boundaries become visually obvious — you see where one error ends and the next begins.

Explicit logging.* calls always show their own timestamp regardless — they're discrete events.

Long lines

Hard cap at 10 000 characters per line. Longer content renders as:

… first 10 000 chars … [truncated, +N chars]

The full text stays in the buffer for future expand support.

Right-click menu

Item	Action
Copy	Same as toolbar
Select all	Select the whole buffer
Clear	Same as toolbar
Emit colour test palette	Inject one line at each severity — quick visual check for your theme

Buffer limits

• Preview lines — 5 000 entries, FIFO eviction
• Editor lines — 1 000 entries, protected from preview-flood eviction

A chatty preview cannot push an editor warning out of the buffer.

Debugging your behavior code

Several ways to surface what your code is doing, from least to most structured. Put any of these inside your Event Handlers and run Preview — output lands in the Console.

1. Quick print (preview only)

def on_score_change(self):
    print(f"score = {self.score}")

Works inside a preview run; output renders with the default stdout style. Doesn't show in editor code — use logging for that.

2. Severity-tagged logging (preview + editor)

import logging
log = logging.getLogger("game")

def on_button_click(self):
    log.debug("clicked at frame %d", self.frame)
    log.info("score: %s", self.score)
    log.warning("low health: %d", self.health)
    log.error("failed to load %s", path)
    log.critical("save file corrupted")

Each level renders in its own color (see the severity table above). The first arg is the format string; remaining args fill in lazily — cheaper than f-strings when DEBUG is hidden by the filter.

3. Catch and log exceptions

def on_load_clicked(self):
    try:
        self._load_save_file()
    except OSError:
        log.exception("save file load failed")

log.exception(...) is log.error(...) plus the full traceback, automatic — use it inside an except clause.

4. Assertions

def update_health(self, value):
    assert 0 <= value <= 100, f"health out of range: {value}"
    self.health = value

A failing assert raises AssertionError, which the Tk callback handler routes to the Console with a red traceback — same path as any other unhandled exception.

5. Inspect a value mid-execution

Drop a one-line log.debug(...) instead of reaching for a breakpoint — fast iteration during a preview loop:

def step_physics(self):
    self.vx += self.ax
    log.debug("vx after gravity: %.2f", self.vx)
    self.x += self.vx

The Debug filter is off by default — enable it on the toolbar to see these lines.

6. Distinct logger per page or system

log = logging.getLogger(f"page.{__name__}")
# or per subsystem
physics_log = logging.getLogger("game.physics")
ui_log = logging.getLogger("game.ui")

Lines render as INFO | game.physics | … — search the Console (Ctrl+F) by logger name to isolate one subsystem when several are chatty.

Common gotchas

• print() in CTkMaker app code doesn't show. Only preview-process print() is captured. Use logging.info(...) for editor-side debug output — see Event Handlers.
• Counter shows N, but no lines visible. A filter is hiding the level. Check the Info / Warn / Error / Debug boxes.
• Third-party noise (PIL, urllib3, matplotlib, asyncio) is muted to WARNING by default. Re-enable per logger with logging.getLogger("PIL").setLevel(logging.DEBUG) if you need to debug image decoding.
• Preview output goes elsewhere. Settings → Preview console mode picks between In-app (capture here), Windows console (separate cmd window), and Off (discarded).

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See also — Preview · Event Handlers · Settings · Keyboard Shortcuts