from flask import Flask, render_template
app = Flask(__name__)
@app.route('/')
def index():
return render_template('index.html')
@app.route('/hello/<name>')
def hello(name):
return render_template('page.html', name=name)
if __name__ == '__main__':
app.run(debug=True, host='0.0.0.0')
当用户按下屏幕上的href链接时,我目前可以使用html a href导航到下一页。
index.html:
<html>
<head>
<link rel="stylesheet" href='/static/style3.css' />
</head>
<body>
<h1>Hello from a template!</h1>
<p><a href='/hello/test'>Go to hello link</a> is a link to a page on this website.</p>
</body>
</html>
但是,我有一个条形码扫描仪(使用evdev),它将在扫描条形码时触发事件。如何使用此事件导航到下一页?
import evdev
from evdev import InputDevice, categorize, ecodes
dev = InputDevice('/dev/input/event1')
# Provided as an example taken from my own keyboard attached to a Centos 6 box:
scancodes = {
# Scancode: ASCIICode
0: None, 1: u'ESC', 2: u'1', 3: u'2', 4: u'3', 5: u'4', 6: u'5', 7: u'6', 8: u'7', 9: u'8',
10: u'9', 11: u'0', 12: u'-', 13: u'=', 14: u'BKSP', 15: u'TAB', 16: u'q', 17: u'w', 18: u'e', 19: u'r',
20: u't', 21: u'y', 22: u'u', 23: u'i', 24: u'o', 25: u'p', 26: u'[', 27: u']', 28: u'CRLF', 29: u'LCTRL',
30: u'a', 31: u's', 32: u'd', 33: u'f', 34: u'g', 35: u'h', 36: u'j', 37: u'k', 38: u'l', 39: u';',
40: u'"', 41: u'`', 42: u'LSHFT', 43: u'\\', 44: u'z', 45: u'x', 46: u'c', 47: u'v', 48: u'b', 49: u'n',
50: u'm', 51: u',', 52: u'.', 53: u'/', 54: u'RSHFT', 56: u'LALT', 57: u' ', 100: u'RALT'
}
capscodes = {
0: None, 1: u'ESC', 2: u'!', 3: u'@', 4: u'#', 5: u'$', 6: u'%', 7: u'^', 8: u'&', 9: u'*',
10: u'(', 11: u')', 12: u'_', 13: u'+', 14: u'BKSP', 15: u'TAB', 16: u'Q', 17: u'W', 18: u'E', 19: u'R',
20: u'T', 21: u'Y', 22: u'U', 23: u'I', 24: u'O', 25: u'P', 26: u'{', 27: u'}', 28: u'CRLF', 29: u'LCTRL',
30: u'A', 31: u'S', 32: u'D', 33: u'F', 34: u'G', 35: u'H', 36: u'J', 37: u'K', 38: u'L', 39: u':',
40: u'\'', 41: u'~', 42: u'LSHFT', 43: u'|', 44: u'Z', 45: u'X', 46: u'C', 47: u'V', 48: u'B', 49: u'N',
50: u'M', 51: u'<', 52: u'>', 53: u'?', 54: u'RSHFT', 56: u'LALT', 57: u' ', 100: u'RALT'
}
#setup vars
x = ''
caps = False
#grab provides exclusive access to the device
dev.grab()
#loop
for event in dev.read_loop():
if event.type == ecodes.EV_KEY:
data = categorize(event) # Save the event temporarily to introspect it
if data.scancode == 42:
if data.keystate == 1:
caps = True
if data.keystate == 0:
caps = False
if data.keystate == 1: # Down events only
if caps:
key_lookup = u'{}'.format(capscodes.get(data.scancode)) or u'UNKNOWN:[{}]'.format(data.scancode) # Lookup or return UNKNOWN:XX
else:
key_lookup = u'{}'.format(scancodes.get(data.scancode)) or u'UNKNOWN:[{}]'.format(data.scancode) # Lookup or return UNKNOWN:XX
if (data.scancode != 42) and (data.scancode != 28):
x += key_lookup
if(data.scancode == 28):
print x # Print it all out!
x = ''
# need to trigger an event to switch pages