如何从 Tkinter 画布文本项中删除 icursor? [英] How to remove icursor from Tkinter canvas text item?

问题描述

我正在关注 Effbot 的 Tkinter 页面:http://effbot.org/zone/editing-canvas-text-items.htm

我遇到的问题是插入光标后，我似乎无法让它消失！

我如何停止完全编辑?

至于示例，链接页面中的那个将起作用:

# 文件:canvas-editing-example-1.py## 编辑画布项目## fredrik lundh，1998 年 12 月## [e-mail]# http://www.pythonware.com#从 tkinter 导入 *#改成Tkinter使用python 2.x系列类 MyCanvas(框架):def __init__(self, root):Frame.__init__(self, root)self.canvas = Canvas(self)self.canvas.pack(fill=BOTH, expand=1)# 标准绑定self.canvas.bind("", self.set_focus)self.canvas.bind("", self.set_cursor)self.canvas.bind("", self.handle_key)# 向画布添加一些项目self.canvas.create_text(50, 50, text="你好")self.canvas.create_text(50, 100, text="world")定义突出显示(自我，项目):# 标记重点项目.请注意，此代码重新创建了# 每次更新的矩形，但这对于# 这个案例.bbox = self.canvas.bbox(item)self.canvas.delete("突出显示")如果 bbox:i = self.canvas.create_rectangle(bbox，填充=白色"，标签=突出显示")self.canvas.lower(i, item)def has_focus(self):返回 self.canvas.focus()def has_selection(self):# hack 以解决 Tkinter 1.101 (Python 1.5.1) 中的错误返回 self.canvas.tk.call(self.canvas._w, 'select', 'item')def set_focus(self, event):如果 self.canvas.type(CURRENT) != "text":返回self.highlight(当前)# 将焦点移到项目self.canvas.focus_set() # 将焦点移到画布上self.canvas.focus(CURRENT) # 设置焦点到文本项self.canvas.select_from(CURRENT, 0)self.canvas.select_to(当前，结束)def set_cursor(self, event):# 移动插入光标item = self.has_focus()如果不是项目:返回 # 或做其他事情# 转换到画布坐标系x = self.canvas.canvasx(event.x)y = self.canvas.canvasy(event.y)self.canvas.icursor(item, "@%d,%d" % (x, y))self.canvas.select_clear()def handle_key(self, event):# 小部件范围的密钥调度程序item = self.has_focus()如果不是项目:返回插入 = self.canvas.index(item, INSERT)如果 event.char >= " ":# 可打印字符如果 self.has_selection():self.canvas.dchars(项目，SEL_FIRST，SEL_LAST)self.canvas.select_clear()self.canvas.insert(item, "insert", event.char)self.highlight(item)elif event.keysym == "BackSpace":如果 self.has_selection():self.canvas.dchars(项目，SEL_FIRST，SEL_LAST)self.canvas.select_clear()别的:如果插入 >0:self.canvas.dchars(item, insert-1, insert)self.highlight(item)# 导航elif event.keysym ==家":self.canvas.icursor(item, 0)self.canvas.select_clear()elif event.keysym ==结束":self.canvas.icursor(项目，结束)self.canvas.select_clear()elif event.keysym ==对":self.canvas.icursor(项目，插入+1)self.canvas.select_clear()elif event.keysym ==左":self.canvas.icursor(item, insert-1)self.canvas.select_clear()别的:pass # 打印 event.keysym# 尝试一下(双击文本以启用编辑)c = MyCanvas(Tk())c.pack()主循环()

双击要编辑的项目之一后，我无法使光标消失；我试过移动焦点并将索引设置为 -1，但似乎都不起作用.

解决方案

self.canvas.focus("")

<块引用>

要从项目中移除焦点，请使用空字符串调用此方法.参考

<小时>

您可以添加以下内容

self.canvas.focus_set() # 将焦点移动到画布窗口self.canvas.focus("") # 从当前拥有它的项目中移除焦点

到

def set_focus(self, event):如果 self.canvas.type(CURRENT) != "text":#这里返回

因此，当用户双击画布上不是由 canvas.create_text 创建的任何部分或项目时，焦点将从当前文本"项目中移除，从而停止编辑.

<小时>

另外你可以添加

self.canvas.delete("highlight")

移除焦点时移除文本周围的白色矩形.

I'm following along with Effbot's Tkinter page here: http://effbot.org/zone/editing-canvas-text-items.htm

The trouble I'm having is that after inserting the icursor, I can't seem to get it to go away!

How do I stop editing altogether?

As for examples, the one from the linked page will work:

# File: canvas-editing-example-1.py
#
# editing canvas items
#
# fredrik lundh, december 1998
#
# [e-mail]
# http://www.pythonware.com
#

from tkinter import *
#Change to Tkinter to use python 2.x series
class MyCanvas(Frame):

    def __init__(self, root):
        Frame.__init__(self, root)

        self.canvas = Canvas(self)
        self.canvas.pack(fill=BOTH, expand=1)

        # standard bindings
        self.canvas.bind("<Double-Button-1>", self.set_focus)
        self.canvas.bind("<Button-1>", self.set_cursor)
        self.canvas.bind("<Key>", self.handle_key)

        # add a few items to the canvas
        self.canvas.create_text(50, 50, text="hello")
        self.canvas.create_text(50, 100, text="world")

    def highlight(self, item):
        # mark focused item.  note that this code recreates the
        # rectangle for each update, but that's fast enough for
        # this case.
        bbox = self.canvas.bbox(item)
        self.canvas.delete("highlight")
        if bbox:
            i = self.canvas.create_rectangle(
                bbox, fill="white",
                tag="highlight"
                )
            self.canvas.lower(i, item)

    def has_focus(self):
        return self.canvas.focus()

    def has_selection(self):
        # hack to work around bug in Tkinter 1.101 (Python 1.5.1)
        return self.canvas.tk.call(self.canvas._w, 'select', 'item')

    def set_focus(self, event):
        if self.canvas.type(CURRENT) != "text":
            return

        self.highlight(CURRENT)

        # move focus to item
        self.canvas.focus_set() # move focus to canvas
        self.canvas.focus(CURRENT) # set focus to text item
        self.canvas.select_from(CURRENT, 0)
        self.canvas.select_to(CURRENT, END)

    def set_cursor(self, event):
        # move insertion cursor
        item = self.has_focus()
        if not item:
            return # or do something else

        # translate to the canvas coordinate system
        x = self.canvas.canvasx(event.x)
        y = self.canvas.canvasy(event.y)

        self.canvas.icursor(item, "@%d,%d" % (x, y))
        self.canvas.select_clear()

    def handle_key(self, event):
        # widget-wide key dispatcher
        item = self.has_focus()
        if not item:
            return

        insert = self.canvas.index(item, INSERT)

        if event.char >= " ":
            # printable character
            if self.has_selection():
                self.canvas.dchars(item, SEL_FIRST, SEL_LAST)
                self.canvas.select_clear()
            self.canvas.insert(item, "insert", event.char)
            self.highlight(item)

        elif event.keysym == "BackSpace":
            if self.has_selection():
                self.canvas.dchars(item, SEL_FIRST, SEL_LAST)
                self.canvas.select_clear()
            else:
                if insert > 0:
                    self.canvas.dchars(item, insert-1, insert)
            self.highlight(item)

        # navigation
        elif event.keysym == "Home":
            self.canvas.icursor(item, 0)
            self.canvas.select_clear()
        elif event.keysym == "End":
            self.canvas.icursor(item, END)
            self.canvas.select_clear()
        elif event.keysym == "Right":
            self.canvas.icursor(item, insert+1)
            self.canvas.select_clear()
        elif event.keysym == "Left":
            self.canvas.icursor(item, insert-1)
            self.canvas.select_clear()

        else:
            pass # print event.keysym

# try it out (double-click on a text to enable editing)
c = MyCanvas(Tk())
c.pack()

mainloop()

After you double click on one of the items to be edited, I cannot make the cursor go away; I've tried moving focus and setting the index to -1, but neither seems to work.

解决方案

self.canvas.focus("")

To remove focus from the item, call this method with an empty string. Reference

---

you can add the following

self.canvas.focus_set() # move focus to canvas window
self.canvas.focus("") # remove focus from the current item that has it

To

def set_focus(self, event):
    if self.canvas.type(CURRENT) != "text":
        #Here
        return

So when the user double-clicks on any part or item of the canvas that isn't created by canvas.create_text the focus is removed from the current "text" item, hence stopping the edit.

---

Plus you can add

self.canvas.delete("highlight")

to remove the white rectangle around the text, when focus is removed.

这篇关于如何从 Tkinter 画布文本项中删除 icursor?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！