这里是我想要的描述:在tkinter画布中绘制几何对象(在此为矩形)的集合,然后蜜蜂通过鼠标探索该画布。单击并拖动以移动画布,滚动放大和缩小。
使用本主题,我找到了单击和拖动部分:使用Mousewith-mouse 移动tkinter画布
我设法写了一些滚动缩放。移动和缩放都可以很好地分开工作。
问题 :如果移动然后放大,则变焦的焦点不再是光标所在的位置。
有什么建议吗?
这是一段要测试的代码
[ 编辑 :现在应该适用于linux和Windows]
import Tkinter as tk import random class Example(tk.Frame): def __init__(self, root): tk.Frame.__init__(self, root) self.canvas = tk.Canvas(self, width=400, height=400, background="bisque") self.xsb = tk.Scrollbar(self, orient="horizontal", command=self.canvas.xview) self.ysb = tk.Scrollbar(self, orient="vertical", command=self.canvas.yview) self.canvas.configure(yscrollcommand=self.ysb.set, xscrollcommand=self.xsb.set) self.canvas.configure(scrollregion=(0,0,1000,1000)) self.xsb.grid(row=1, column=0, sticky="ew") self.ysb.grid(row=0, column=1, sticky="ns") self.canvas.grid(row=0, column=0, sticky="nsew") self.grid_rowconfigure(0, weight=1) self.grid_columnconfigure(0, weight=1) #Plot some rectangles for n in range(50): x0 = random.randint(0, 900) y0 = random.randint(50, 900) x1 = x0 + random.randint(50, 100) y1 = y0 + random.randint(50,100) color = ("red", "orange", "yellow", "green", "blue")[random.randint(0,4)] self.canvas.create_rectangle(x0,y0,x1,y1, outline="black", fill=color, activefill="black", tags=n) self.canvas.create_text(50,10, anchor="nw", text="Click and drag to move the canvas\nScroll to zoom.") # This is what enables using the mouse: self.canvas.bind("<ButtonPress-1>", self.move_start) self.canvas.bind("<B1-Motion>", self.move_move) #linux scroll self.canvas.bind("<Button-4>", self.zoomerP) self.canvas.bind("<Button-5>", self.zoomerM) #windows scroll self.canvas.bind("<MouseWheel>",self.zoomer) #move def move_start(self, event): self.canvas.scan_mark(event.x, event.y) def move_move(self, event): self.canvas.scan_dragto(event.x, event.y, gain=1) #windows zoom def zoomer(self,event): if (event.delta > 0): self.canvas.scale("all", event.x, event.y, 1.1, 1.1) elif (event.delta < 0): self.canvas.scale("all", event.x, event.y, 0.9, 0.9) self.canvas.configure(scrollregion = self.canvas.bbox("all")) #linux zoom def zoomerP(self,event): self.canvas.scale("all", event.x, event.y, 1.1, 1.1) self.canvas.configure(scrollregion = self.canvas.bbox("all")) def zoomerM(self,event): self.canvas.scale("all", event.x, event.y, 0.9, 0.9) self.canvas.configure(scrollregion = self.canvas.bbox("all")) if __name__ == "__main__": root = tk.Tk() Example(root).pack(fill="both", expand=True) root.mainloop()
鼠标事件在“屏幕坐标”中报告。当您使用滚动画布时,通常需要将这些数字转换为“画布(即,滚动区域)坐标”。
例如。为您的变焦焦点:
true_x = canvas.canvasx(event.x) true_y = canvas.canvasy(event.y)