python pyQt5 二叉树可视化

以下是一个简单的使用PyQt5实现二叉树可视化的示例代码：

1. 安装PyQt5库：

pip install PyQt5

2. 导入必要的库：

from PyQt5.QtCore import Qt, QRectF
from PyQt5.QtGui import QPainter, QFont, QPen
from PyQt5.QtWidgets import QApplication, QGraphicsScene, QGraphicsView, QGraphicsItem, QGraphicsTextItem

3. 定义节点类：

class Node(QGraphicsItem):
    def __init__(self, value, x=0, y=0):
        super().__init__()
        self.value = value
        self.left = None
        self.right = None
        self.x = x
        self.y = y
        self.width = 40
        self.height = 30
        self.pen = QPen(Qt.black)
        self.brush = Qt.white

    def boundingRect(self):
        return QRectF(self.x, self.y, self.width, self.height)

    def paint(self, painter, option, widget):
        painter.setPen(self.pen)
        painter.setBrush(self.brush)
        painter.drawRect(self.x, self.y, self.width, self.height)
        font = QFont('Arial', 12)
        painter.setFont(font)
        painter.drawText(self.boundingRect(), Qt.AlignCenter, str(self.value))

4. 定义二叉树类：

class BinaryTree():
    def __init__(self):
        self.root = None

    def insert(self, value):
        if not self.root:
            self.root = Node(value)
        else:
            self._insert(value, self.root)

    def _insert(self, value, node):
        if value < node.value:
            if node.left:
                self._insert(value, node.left)
            else:
                node.left = Node(value, node.x - 50, node.y + 50)
        else:
            if node.right:
                self._insert(value, node.right)
            else:
                node.right = Node(value, node.x + 50, node.y + 50)

    def traverse(self):
        if self.root:
            self._traverse(self.root)

    def _traverse(self, node):
        if node.left:
            self._traverse(node.left)
        print(node.value)
        if node.right:
            self._traverse(node.right)

5. 定义图形场景类：

class GraphicsScene(QGraphicsScene):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.setSceneRect(0, 0, 500, 500)
        self.nodes = []

    def addNode(self, node):
        self.addItem(node)

    def drawLine(self, parent, child):
        self.addLine(parent.x + parent.width / 2, parent.y + parent.height, child.x + child.width / 2, child.y)

6. 定义主窗口类：

class MainWindow(QGraphicsView):
    def __init__(self):
        super().__init__()
        self.setWindowTitle('Binary Tree Visualization')
        self.setRenderHint(QPainter.Antialiasing)
        self.setDragMode(QGraphicsView.ScrollHandDrag)
        self.setScene(GraphicsScene())

        self.tree = BinaryTree()
        self.tree.insert(50)
        self.tree.insert(30)
        self.tree.insert(70)
        self.tree.insert(20)
        self.tree.insert(40)
        self.tree.insert(60)
        self.tree.insert(80)

        self.drawTree()

    def drawTree(self):
        self.drawNode(self.tree.root)
        self.drawLines(self.tree.root)

    def drawNode(self, node):
        scene = self.scene()
        scene.addNode(node)
        scene.nodes.append(node)
        if node.left:
            self.drawNode(node.left)
        if node.right:
            self.drawNode(node.right)

    def drawLines(self, node):
        scene = self.scene()
        if node.left:
            scene.drawLine(node, node.left)
            self.drawLines(node.left)
        if node.right:
            scene.drawLine(node, node.right)
            self.drawLines(node.right)

7. 运行主窗口：

if __name__ == '__main__':
    app = QApplication([])
    mainWindow = MainWindow()
    mainWindow.show()
    app.exec_()

以上代码可以实现一个简单的二叉树可视化，可以根据需要进行修改和扩展。