fix: painel direito do editor com largura fixa e botão abrir PDF na toolbar

Substituir QSplitter por QHBoxLayout para o painel de controlos ter
largura fixa de 400px sem ultrapassar os limites da janela. Adicionar
botão "Abrir PDF" permanente na barra de workspace.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: nelsonduarte

app/editor/tab.py

@@ -5,7 +5,7 @@
 from PySide6.QtCore import Qt, QEvent
 from PySide6.QtWidgets import (
     QWidget, QVBoxLayout, QHBoxLayout, QLabel, QPushButton,
-    QScrollArea, QFrame, QSplitter, QStackedWidget, QGroupBox,
+    QScrollArea, QFrame, QStackedWidget, QGroupBox,
     QGridLayout, QLayout, QSizePolicy, QListWidget, QTableWidget,
     QTableWidgetItem, QHeaderView, QTextEdit, QComboBox, QFileDialog,
     QMessageBox, QDialog, QApplication,
@@ -49,7 +49,9 @@ def __init__(self, status_fn):
                                   "Clica ou arrasta directamente no PDF para editar."))
 
         # body: canvas esquerda | controlos direita
-        body = QSplitter(Qt.Orientation.Horizontal)
+        body = QWidget()
+        body_h = QHBoxLayout(body)
+        body_h.setContentsMargins(0, 0, 0, 0); body_h.setSpacing(0)
 
         self._canvas = PdfEditCanvas()
         self._canvas.rect_selected.connect(self._on_rect)
@@ -61,13 +63,12 @@ def __init__(self, status_fn):
         canvas_scroll.setMinimumWidth(320)
         canvas_scroll.viewport().installEventFilter(self)
         self._canvas_scroll = canvas_scroll
-        body.addWidget(canvas_scroll)
+        body_h.addWidget(canvas_scroll, 1)
 
         # painel de controlos (scrollavel)
         ctrl_inner = QWidget(); ctrl_inner.setObjectName("scroll_inner")
-        ctrl_inner.setMinimumWidth(0)
+        ctrl_inner.setFixedWidth(380)
         cv = QVBoxLayout(ctrl_inner); cv.setContentsMargins(10, 10, 10, 10); cv.setSpacing(8)
-        cv.setSizeConstraint(QLayout.SizeConstraint.SetNoConstraint)
 
         # -- Ficheiro PDF --
         grp_file = QGroupBox("Ficheiro PDF")
@@ -229,20 +230,14 @@ def __init__(self, status_fn):
         cv.addWidget(grp_save)
         cv.addStretch()
 
-        # forçar largura mínima zero em todos os groupboxes do painel direito
-        for gb in ctrl_inner.findChildren(QGroupBox):
-            gb.setMinimumWidth(0)
-
         ctrl_scroll = QScrollArea()
         ctrl_scroll.setWidgetResizable(True)
         ctrl_scroll.setFrameShape(QFrame.Shape.NoFrame)
-        ctrl_scroll.setHorizontalScrollBarPolicy(Qt.ScrollBarPolicy.ScrollBarAsNeeded)
+        ctrl_scroll.setHorizontalScrollBarPolicy(Qt.ScrollBarPolicy.ScrollBarAlwaysOff)
         ctrl_scroll.setWidget(ctrl_inner)
-        ctrl_scroll.setMinimumWidth(180)
-        body.addWidget(ctrl_scroll)
-        body.setSizes([800, 360])
-        body.setStretchFactor(0, 1)
-        body.setStretchFactor(1, 0)
+        ctrl_scroll.setFixedWidth(400)
+        ctrl_scroll.setSizePolicy(QSizePolicy.Policy.Fixed, QSizePolicy.Policy.Expanding)
+        body_h.addWidget(ctrl_scroll)
         root.addWidget(body, 1)
 
         action_bar, _ = ActionBar("Aplicar e Guardar", self._run)

app/window.py

@@ -85,6 +85,14 @@ def __init__(self):
         wb_col.addWidget(wb_title); wb_col.addWidget(wb_hint)
         wb_h.addLayout(wb_col, 1)
 
+        self._open_pdf_btn = QPushButton()
+        self._open_pdf_btn.setIcon(qta.icon("fa5s.folder-open", color=TEXT_PRI))
+        self._open_pdf_btn.setObjectName("viewer_nav_btn")
+        self._open_pdf_btn.setFixedSize(28, 28)
+        self._open_pdf_btn.setToolTip("Abrir PDF")
+        self._open_pdf_btn.clicked.connect(self._open_pdf)
+        wb_h.addWidget(self._open_pdf_btn)
+
         self._quick_merge_btn = QPushButton("Juntar"); self._quick_merge_btn.setObjectName("quick_btn")
         self._quick_ocr_btn = QPushButton("OCR"); self._quick_ocr_btn.setObjectName("quick_btn")
         self._quick_edit_btn = QPushButton("Editar"); self._quick_edit_btn.setObjectName("quick_btn")
@@ -264,6 +272,13 @@ def _on_nav_clicked(self, item):
             if row == edit_idx:
                 self._setup_zoom_bar(True)
 
+    def _open_pdf(self):
+        from PySide6.QtWidgets import QFileDialog
+        path, _ = QFileDialog.getOpenFileName(
+            self, "Abrir PDF", "", "PDF Files (*.pdf);;All (*.*)")
+        if path:
+            self._viewer.load(path)
+
     def _set_status(self, msg: str):
         self._sb.showMessage(msg)