Fix QML runtime type errors and add CI

.github/workflows/ci.yml

@@ -0,0 +1,29 @@
+name: CI
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  lint-qml:
+    name: QML lint & type check
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Install Qt 6 and xvfb
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends \
+            qt6-declarative-dev-tools \
+            qml-qt6 \
+            qml6-module-qtquick \
+            qml6-module-qtquick-controls \
+            qml6-module-qtquick-layouts \
+            qml6-module-qtquick-window \
+            qml6-module-qtquick-templates \
+            xvfb
+
+      - name: Run QML checks
+        run: ./scripts/lint-qml.sh

components/LoginForm.qml

@@ -47,7 +47,7 @@ Item {
             color: root.textColor
             font.pointSize: root.fontSize + 8
             font.weight: Font.Light
-            font.family: root.fontFamily || undefined
+            font.family: root.fontFamily
             renderType: Text.NativeRendering
         }
 
@@ -59,7 +59,7 @@ Item {
             placeholderText: "Username"
             text: root.defaultUsername
             font.pointSize: root.fontSize
-            font.family: root.fontFamily || undefined
+            font.family: root.fontFamily
 
             color: root.textColor
             placeholderTextColor: Qt.rgba(1, 1, 1, 0.5)
@@ -86,7 +86,7 @@ Item {
             placeholderText: "Password"
             echoMode: TextInput.Password
             font.pointSize: root.fontSize
-            font.family: root.fontFamily || undefined
+            font.family: root.fontFamily
 
             color: root.textColor
             placeholderTextColor: Qt.rgba(1, 1, 1, 0.5)
@@ -122,7 +122,7 @@ Item {
             height: 44
             text: "Log In"
             font.pointSize: root.fontSize
-            font.family: root.fontFamily || undefined
+            font.family: root.fontFamily
 
             contentItem: Text {
                 text: loginButton.text

components/SessionSelector.qml

@@ -28,7 +28,7 @@ Item {
         textRole: "name"
 
         font.pointSize: root.fontSize
-        font.family: root.fontFamily || undefined
+        font.family: root.fontFamily
 
         contentItem: Text {
             leftPadding: 10

preview/Preview.qml

@@ -32,6 +32,8 @@ Window {
 
     QtObject {
         id: mockConfig
+        // Set to "" to use the solid fallback color, or provide a path
+        // to an image (e.g. drop your own into assets/background.jpg).
         property string background: Qt.resolvedUrl("../assets/background.jpg")
         property string type: "image"
         property string color: "#1a1a2e"
@@ -121,9 +123,14 @@ Window {
     Image {
         id: backgroundImage
         anchors.fill: parent
-        source: mockConfig.background
+        source: mockConfig.background || ""
         fillMode: Image.PreserveAspectCrop
         asynchronous: true
+        onStatusChanged: {
+            if (status === Image.Error && source != "")
+                console.log("Background image not found — using fallback color. " +
+                    "Drop an image into assets/background.jpg or update theme.conf.")
+        }
     }
 
     Rectangle {

scripts/lint-qml.sh

@@ -0,0 +1,110 @@
+#!/usr/bin/env bash
+#
+# lint-qml.sh - Static analysis and runtime type-error check for QML files.
+#
+# Runs qmllint (static) on all QML source files, then launches the preview
+# under xvfb for a few seconds to catch runtime type-assignment warnings.
+#
+# Usage:  ./scripts/lint-qml.sh
+#
+# Exit codes:
+#   0  All checks passed
+#   1  qmllint found issues or runtime errors detected
+
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_DIR="$(cd "$SCRIPT_DIR/.." && pwd)"
+
+cd "$PROJECT_DIR"
+
+# ── Locate Qt 6 tools ────────────────────────────────────────────
+# Binary names and paths vary across distros:
+#   Arch:   qmllint, qml6          (on PATH)
+#   Ubuntu: qmllint, qml           (in /usr/lib/qt6/bin)
+for candidate in /usr/lib/qt6/bin /usr/lib64/qt6/bin; do
+    [[ -d "$candidate" ]] && export PATH="$candidate:$PATH"
+done
+
+find_tool() {
+    for name in "$@"; do
+        if command -v "$name" &>/dev/null; then
+            echo "$name"
+            return
+        fi
+    done
+    echo ""
+}
+
+QMLLINT=$(find_tool qmllint qmllint6)
+QML_RUNTIME=$(find_tool qml6 qml)
+
+FAILED=0
+
+# ── Static analysis with qmllint ──────────────────────────────────
+echo "=== qmllint: static analysis ==="
+
+if [[ -z "$QMLLINT" ]]; then
+    echo "SKIP: qmllint not found."
+else
+    QML_FILES=$(find . -name '*.qml' -not -path './.git/*')
+    echo "Checking: $QML_FILES"
+    echo ""
+
+    # qmllint emits warnings for SDDM context properties (sddm, config,
+    # userModel, etc.) that only exist at runtime. These are expected and
+    # unavoidable. We capture the output and only fail on actual errors
+    # (syntax errors, unknown components from our own code), not warnings
+    # about unqualified/unresolved access to SDDM injected globals.
+    LINT_OUTPUT=$($QMLLINT $QML_FILES 2>&1) || true
+    if echo "$LINT_OUTPUT" | grep -qiE '^Error:'; then
+        echo "$LINT_OUTPUT"
+        echo "FAIL: qmllint found errors."
+        FAILED=1
+    else
+        echo "PASS: qmllint clean (warnings only)."
+    fi
+fi
+echo ""
+
+# ── Runtime type-error check ──────────────────────────────────────
+echo "=== Runtime: checking for type errors ==="
+
+if [[ -z "$QML_RUNTIME" ]]; then
+    echo "SKIP: qml runtime not found (tried qml6, qml)."
+    echo ""
+    exit $FAILED
+fi
+
+# Use the Basic style to avoid Breeze/Plasma-specific errors that only
+# occur outside a full Plasma session (e.g. T.Overlay in ComboBox).
+export QT_QUICK_CONTROLS_STYLE=Basic
+
+STDERR_LOG=$(mktemp)
+trap 'rm -f "$STDERR_LOG"' EXIT
+
+# Run preview for 3 seconds under a virtual framebuffer, capture stderr.
+if command -v xvfb-run &>/dev/null; then
+    timeout 3 xvfb-run -a "$QML_RUNTIME" preview/Preview.qml 2>"$STDERR_LOG" || true
+elif [ -n "${DISPLAY:-}" ] || [ -n "${WAYLAND_DISPLAY:-}" ]; then
+    timeout 3 "$QML_RUNTIME" preview/Preview.qml 2>"$STDERR_LOG" || true
+else
+    echo "SKIP: no display and xvfb-run not available."
+    echo ""
+    exit $FAILED
+fi
+
+# Filter for errors we care about (type assignment, ReferenceError, TypeError).
+if grep -E 'Unable to assign|ReferenceError|TypeError' "$STDERR_LOG" \
+    | grep -v 'Cannot open:' \
+    | grep -q .; then
+    echo "FAIL: runtime type errors detected:"
+    grep -E 'Unable to assign|ReferenceError|TypeError' "$STDERR_LOG" \
+        | grep -v 'Cannot open:'
+    FAILED=1
+else
+    echo "PASS: no runtime type errors."
+fi
+echo ""
+
+exit $FAILED

scripts/preview.sh

@@ -13,6 +13,22 @@ set -euo pipefail
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 PROJECT_DIR="$(cd "$SCRIPT_DIR/.." && pwd)"
 
+ENTR_PID=""
+
+cleanup() {
+    trap - SIGINT SIGTERM   # prevent re-entry
+    [[ -n "$ENTR_PID" ]] && kill "$ENTR_PID" 2>/dev/null && wait "$ENTR_PID" 2>/dev/null
+    echo ""
+    echo "Preview stopped."
+    exit 0
+}
+trap cleanup SIGINT SIGTERM
+
+# Force the Basic Qt Quick Controls style so the standalone preview doesn't
+# load Breeze, which depends on Plasma-specific overlay types that are
+# unavailable outside a full Plasma session.
+export QT_QUICK_CONTROLS_STYLE=Basic
+
 echo "=== KDE Lockscreen Builder — Live Preview ==="
 echo "Project: $PROJECT_DIR"
 echo "Press Ctrl+C to stop"
@@ -22,5 +38,8 @@ cd "$PROJECT_DIR"
 
 while true; do
     find . \( -name '*.qml' -o -name '*.conf' -o -name '*.jpg' -o -name '*.png' -o -name '*.svg' \) \
-        | entr -d -r qml6 preview/Preview.qml
+        | entr -d -r qml6 preview/Preview.qml &
+    ENTR_PID=$!
+    wait "$ENTR_PID" || true
+    ENTR_PID=""
 done