# 📚 PyQt5 Tutorial - Part 2/6: Advanced Widgets & Customization
#PyQt5 #PythonGUI #AdvancedWidgets #QSS #SignalsSlots

Welcome to Part 2 of our PyQt5 series! This in-depth lesson covers advanced widgets, custom styling, multi-window applications, and professional patterns.

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## 🔹 Advanced Widgets Overview
### 1. Tabbed Interfaces (QTabWidget)

from PyQt5.QtWidgets import QTabWidget, QTextEdit, QWidget

class TabDemo(QWidget):
    def __init__(self):
        super().__init__()
        
        tabs = QTabWidget()
        
        # Tab 1: Text Editor
        tab1 = QWidget()
        text_edit = QTextEdit()
        tab1_layout = QVBoxLayout()
        tab1_layout.addWidget(text_edit)
        tab1.setLayout(tab1_layout)
        
        # Tab 2: Settings
        tab2 = QWidget()
        tab2_layout = QVBoxLayout()
        tab2_layout.addWidget(QLabel("Settings Panel"))
        tab2.setLayout(tab2_layout)
        
        tabs.addTab(tab1, "Editor")
        tabs.addTab(tab2, "Settings")
        
        main_layout = QVBoxLayout()
        main_layout.addWidget(tabs)
        self.setLayout(main_layout)

### 2. Tree Widget (QTreeWidget)

def setup_file_tree(self):
    tree = QTreeWidget()
    tree.setHeaderLabels(["Name", "Size", "Type"])
    
    # Add parent items
    root = QTreeWidgetItem(tree)
    root.setText(0, "Project Root")
    
    # Add children
    for file in ["main.py", "config.ini", "README.md"]:
        child = QTreeWidgetItem(root)
        child.setText(0, file)
        child.setText(1, "10 KB")
        child.setText(2, "Python" if file.endswith(".py") else "Text")
    
    tree.expandAll()
    return tree

### 3. Table Widget (QTableWidget)

def setup_data_table(self):
    table = QTableWidget(5, 3)  # Rows, columns
    table.setHorizontalHeaderLabels(["ID", "Name", "Status"])
    
    sample_data = [
        [101, "Product A", "Active"],
        [102, "Product B", "Inactive"],
        [103, "Product C", "Pending"]
    ]
    
    for row, data in enumerate(sample_data):
        for col, text in enumerate(data):
            item = QTableWidgetItem(str(text))
            table.setItem(row, col, item)
    
    table.resizeColumnsToContents()
    return table

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## 🔹 Custom Signals & Slots
### 1. Creating Custom Signals

from PyQt5.QtCore import pyqtSignal, QObject

class Worker(QObject):
    progress_changed = pyqtSignal(int)
    task_completed = pyqtSignal(str)
    
    def run_task(self):
        for i in range(1, 101):
            time.sleep(0.05)
            self.progress_changed.emit(i)
        self.task_completed.emit("Task finished!")

### 2. Advanced Signal-Slot Connections

# Multiple signals to single slot
button1.clicked.connect(self.handle_click)
button2.clicked.connect(self.handle_click)

# Signal with arguments
self.worker.progress_changed.connect(self.update_progress_bar)

# Lambda slots
button.clicked.connect(lambda: self.process_data(param1, param2))

# Slot decorator
@pyqtSlot()
def on_button_click(self):
    print("Button clicked!")

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## 🔹 Styling with Qt Style Sheets (QSS)
### 1. Basic Styling

app.setStyleSheet("""
    QPushButton {
        background-color: #4CAF50;
        border: none;
        color: white;
        padding: 8px 16px;
        font-size: 14px;
    }
    QPushButton:hover {
        background-color: #45a049;
    }
    QLineEdit {
        padding: 5px;
        border: 1px solid #ccc;
        border-radius: 3px;
    }
""")

### 2. Advanced Selectors

/* Style only buttons in the toolbar */
QToolBar QPushButton {
    min-width: 80px;
}

/* Style checked checkboxes differently */
QCheckBox:checked {
    color: #0085FF;
}

/* Style odd/even table rows */
QTableView::item:alternate {
    background: #f0f0f0;
}

### 3. Dynamic Style Changes

# Change style programmatically
button.setStyleSheet("""
    QPushButton {
        background-color: red;
        font-weight: bold;
    }
""")

# Reset to default
button.setStyleSheet("")

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