Python xlib更改光标 [英] Python xlib change cursor

问题描述

如何使用Xlib在python应用程序中为根窗口(或任何其他窗口)设置光标?

How can I set the cursor for the root window (or any other window) in a python application using Xlib?

我有一个display和window(根窗口)的实例. 使用C绑定；我可以将 XDefineCursor 与我用 XCreatePixmapCursor .我该如何使用python绑定做同样的事情?

I have an instance of display and window (the root window). Using the C bindings; I could use XDefineCursor with a cursor I have created with XCreatePixmapCursor. How do I do the same with the python bindings?

我希望能够使用默认光标或自定义光标.

I want to be able to use a default cursor, or a custom cursor.

推荐答案

当您需要找到与任何libX11函数等效的python-xlib时，要记住两点:

There are two things you want to keep in mind when you need to find the python-xlib equivalent of any libX11 function:

1. 与libX11不同，python-xlib是面向对象的.在这种情况下，XCreatePixmapCursor()会转换为pixmap.create_cursor().
2. 大多数python-xlib方法直接映射到X11消息，即.大多数辅助功能未实现；如果找不到匹配的python-xlib方法，则通常需要查看 libX11源代码确定该函数是否只是在后台调用其他函数的助手.在这种情况下，如果您查看 XDefineCursor() <<的源代码/a>，您会看到它实际上是在调用XChangeWindowAttributes()，这意味着您将要在python-xlib中使用win.change_attributes().

1. Unlike libX11, python-xlib is object-oriented; In this case, XCreatePixmapCursor() translates to pixmap.create_cursor().
2. Most python-xlib methods map directly to X11 messages, ie. most helper functions aren't implemented; If you can't find a matching python-xlib method, you'll often want to look at the libX11 source code to figure out if the function is just a helper that calls some other function under the hood. In this case, if you look at the source code of XDefineCursor(), you'll see it's actually calling XChangeWindowAttributes(), meaning you'll want to use win.change_attributes() in python-xlib.

如果要使用XCreateFontCursor()来使用光标字体中的光标，则第二条准则再次适用:它在幕后调用XCreateGlyphCursor()，与font.create_glyph_cursor()相对应.

If you want to use XCreateFontCursor() to use a cursor from the cursor font, the second guideline again applies: It's calling XCreateGlyphCursor() under the hood, which corresponds to font.create_glyph_cursor().

将所有内容放在一起，您将获得以下内容:

Putting all of that together, here's what you'll get:

# Create font cursor
font = display.open_font('cursor')
cursor = font.create_glyph_cursor(font, Xlib.Xcursorfont.crosshair, Xlib.Xcursorfont.crosshair+1, (65535, 65535, 65535), (0, 0, 0))


# Use PIL to load a cursor image and ensure that it's 1-bit as required
im = Image.open('cursor.png').convert('1')
w, h = im.size

# Create pixmap cursor
mask = win.create_pixmap(w, h, 1)
gc = mask.create_gc(foreground=0, background=1)
mask.put_pil_image(gc, 0, 0, im)
cursor = mask.create_cursor(mask, (0, 0, 0), (65535, 65535, 65535), 0, 0)


# Change cursors for given windows
win.change_attributes(cursor=cursor)

如果您想知道+1在调用font.create_glyph_cursor()中的重要性，请在

If you're wondering about the significance of the +1 in the call to font.create_glyph_cursor(), that's explained in the source code of XCreateFontCursor().

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