Article Outline
Python pyqt (gui) example 'NinePatch'
NinePatch
Python pyqt example: NinePatch
#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
Created on 2018年10月25日
@author: Irony
@site: https://pyqt5.com , https://github.com/892768447
@email: [email protected]
@file: NinePatch
@description:
"""
from math import fabs
from PyQt5.QtCore import QRect
from PyQt5.QtGui import QImage, QColor, QPainter, qRed, qGreen, qBlue, qAlpha
__Author__ = """By: Irony
QQ: 892768447
Email: [email protected]"""
__Copyright__ = "Copyright (c) 2018 Irony"
__Version__ = "Version 1.0"
class _Exception(Exception):
def __init__(self, imgW, imgH):
self.imgW = imgW
self.imgH = imgH
class NinePatchException(Exception):
def __str__(self):
return "Nine patch error"
class ExceptionIncorrectWidth(_Exception):
def __str__(self):
return "Input incorrect width. Mimimum width = :{imgW}".format(imgW=self.imgW)
class ExceptionIncorrectWidthAndHeight(_Exception):
def __str__(self):
return "Input incorrect width width and height. Minimum width = :{imgW} . Minimum height = :{imgH}".format(imgW=self.imgW, imgH=self.imgH)
class ExceptionIncorrectHeight(_Exception):
def __str__(self):
return "Input incorrect height. Minimum height = :{imgW}".format(imgW=self.imgW)
class ExceptionNot9Patch(Exception):
def __str__(self):
return "It is not nine patch image"
class NinePatch:
def __init__(self, fileName):
self.CachedImage = None # 缓存图片
self.OldWidth = -1
self.OldHeight = -1
self.ResizeDistancesX = []
self.ResizeDistancesY = [] # [(int,int)]数组
self.setImage(fileName)
def width(self):
return self.Image.width()
def height(self):
return self.Image.height()
def setImage(self, fileName):
self.Image = QImage(fileName)
if self.Image.isNull():
return
self.ContentArea = self.GetContentArea()
self.GetResizeArea()
if not self.ResizeDistancesX or not self.ResizeDistancesY:
raise ExceptionNot9Patch
def __del__(self):
if hasattr(self, "CachedImage"):
del self.CachedImage
if hasattr(self, "Image"):
del self.Image
def Draw(self, painter, x, y):
painter.drawImage(x, y, self.CachedImage)
def SetImageSize(self, width, height):
resizeWidth = 0
resizeHeight = 0
for i in range(len(self.ResizeDistancesX)):
resizeWidth += self.ResizeDistancesX[i][1]
for i in range(len(self.ResizeDistancesY)):
resizeHeight += self.ResizeDistancesY[i][1]
if (width < (self.Image.width() - 2 - resizeWidth) and height < (self.Image.height() - 2 - resizeHeight)):
raise ExceptionIncorrectWidthAndHeight(
self.Image.width() - 2, self.Image.height() - 2)
if (width < (self.Image.width() - 2 - resizeWidth)):
raise ExceptionIncorrectWidth(
self.Image.width() - 2, self.Image.height() - 2)
if (height < (self.Image.height() - 2 - resizeHeight)):
raise ExceptionIncorrectHeight(
self.Image.width() - 2, self.Image.height() - 2)
if (width != self.OldWidth or height != self.OldHeight):
self.OldWidth = width
self.OldHeight = height
self.UpdateCachedImage(width, height)
@classmethod
def GetContentAreaRect(self, width, height):
# print("GetContentAreaRect : width:%d height:%d" % (width, height))
return (QRect(self.ContentArea.x(), self.ContentArea.y(), (width - (self.Image.width() - 2 - self.ContentArea.width())),
(height - (self.Image.height() - 2 - self.ContentArea.height()))))
def DrawScaledPart(self, oldRect, newRect, painter):
if (newRect.width() and newRect.height()):
# print("DrawScaledPart newRect.width:%d newRect.height:%d" % (newRect.width() , newRect.height()))
img = self.Image.copy(oldRect)
img = img.scaled(newRect.width(), newRect.height())
painter.drawImage(newRect.x(), newRect.y(), img,
0, 0, newRect.width(), newRect.height())
def DrawConstPart(self, oldRect, newRect, painter):
# print("DrawConstPart oldRect:{oldRect} newRect:{newRect}".format(oldRect = oldRect, newRect = newRect))
img = self.Image.copy(oldRect)
painter.drawImage(newRect.x(), newRect.y(), img, 0,
0, newRect.width(), newRect.height())
def IsColorBlack(self, color):
r = qRed(color)
g = qGreen(color)
b = qBlue(color)
a = qAlpha(color)
if a < 128:
return False
return r < 128 and g < 128 and b < 128
def GetContentArea(self):
j = self.Image.height() - 1
left = 0
right = 0
for i in range(self.Image.width()):
if (self.IsColorBlack(self.Image.pixel(i, j)) and left == 0):
left = i
else:
if (left != 0 and self.IsColorBlack(self.Image.pixel(i, j))):
right = i
if (left and not right):
right = left
left -= 1
i = self.Image.width() - 1
top = 0
bot = 0
for j in range(self.Image.height()):
if (self.IsColorBlack(self.Image.pixel(i, j)) and top == 0):
top = j
else:
if (top and self.IsColorBlack(self.Image.pixel(i, j))):
bot = j
if (top and not bot):
bot = top
top -= 1
# print("GetContentArea left: %d top:%d %d %d" % (left, top, right - left, bot - top))
return (QRect(left, top, right - left, bot - top))
def GetResizeArea(self):
j = 0
left = 0
right = 0
for i in range(self.Image.width()):
if (self.IsColorBlack(self.Image.pixel(i, j)) and left == 0):
left = i
if (left and self.IsColorBlack(self.Image.pixel(i, j)) and not self.IsColorBlack(self.Image.pixel(i + 1, j))):
right = i
left -= 1
# print("ResizeDistancesX.append ", left, " ", right - left)
self.ResizeDistancesX.append((left, right - left))
right = 0
left = 0
i = 0
top = 0
bot = 0
for j in range(self.Image.height()):
if (self.IsColorBlack(self.Image.pixel(i, j)) and top == 0):
top = j
if (top and self.IsColorBlack(self.Image.pixel(i, j)) and not self.IsColorBlack(self.Image.pixel(i, j + 1))):
bot = j
top -= 1
# print("ResizeDistancesY.append ", top, " ", bot - top)
self.ResizeDistancesY.append((top, bot - top))
top = 0
bot = 0
# print(self.ResizeDistancesX, len(self.ResizeDistancesX))
# print(self.ResizeDistancesY, len(self.ResizeDistancesY))
def GetFactor(self, width, height, factorX, factorY):
topResize = width - (self.Image.width() - 2)
leftResize = height - (self.Image.height() - 2)
for i in range(len(self.ResizeDistancesX)):
topResize += self.ResizeDistancesX[i][1]
factorX += self.ResizeDistancesX[i][1]
for i in range(len(self.ResizeDistancesY)):
leftResize += self.ResizeDistancesY[i][1]
factorY += self.ResizeDistancesY[i][1]
factorX = float(topResize) / factorX
factorY = float(leftResize) / factorY
return factorX, factorY
def UpdateCachedImage(self, width, height):
# print("UpdateCachedImage: ", width, " " , height)
self.CachedImage = QImage(
width, height, QImage.Format_ARGB32_Premultiplied)
self.CachedImage.fill(QColor(0, 0, 0, 0))
painter = QPainter(self.CachedImage)
factorX = 0.0
factorY = 0.0
factorX, factorY = self.GetFactor(width, height, factorX, factorY)
# print("after GetFactor: ", width, height, factorX, factorY)
lostX = 0.0
lostY = 0.0
x1 = 0 # for image parts X
y1 = 0 # for image parts Y
# widthResize # width for image parts
# heightResize # height for image parts
resizeX = 0
resizeY = 0
offsetX = 0
offsetY = 0
for i in range(len(self.ResizeDistancesX)):
y1 = 0
offsetY = 0
lostY = 0.0
for j in range(len(self.ResizeDistancesY)):
widthResize = self.ResizeDistancesX[i][0] - x1
heightResize = self.ResizeDistancesY[j][0] - y1
self.DrawConstPart(QRect(x1 + 1, y1 + 1, widthResize, heightResize),
QRect(x1 + offsetX, y1 + offsetY, widthResize, heightResize), painter)
y2 = self.ResizeDistancesY[j][0]
heightResize = self.ResizeDistancesY[j][1]
resizeY = round(float(heightResize) * factorY)
lostY += resizeY - (float(heightResize) * factorY)
if (fabs(lostY) >= 1.0):
if (lostY < 0):
resizeY += 1
lostY += 1.0
else:
resizeY -= 1
lostY -= 1.0
self.DrawScaledPart(QRect(x1 + 1, y2 + 1, widthResize, heightResize),
QRect(x1 + offsetX, y2 + offsetY, widthResize, resizeY), painter)
x2 = self.ResizeDistancesX[i][0]
widthResize = self.ResizeDistancesX[i][1]
heightResize = self.ResizeDistancesY[j][0] - y1
resizeX = round(float(widthResize) * factorX)
lostX += resizeX - (float(widthResize) * factorX)
if (fabs(lostX) >= 1.0):
if (lostX < 0):
resizeX += 1
lostX += 1.0
else:
resizeX -= 1
lostX -= 1.0
self.DrawScaledPart(QRect(x2 + 1, y1 + 1, widthResize, heightResize),
QRect(x2 + offsetX, y1 + offsetY, resizeX, heightResize), painter)
heightResize = self.ResizeDistancesY[j][1]
self.DrawScaledPart(QRect(x2 + 1, y2 + 1, widthResize, heightResize),
QRect(x2 + offsetX, y2 + offsetY, resizeX, resizeY), painter)
y1 = self.ResizeDistancesY[j][0] + self.ResizeDistancesY[j][1]
offsetY += resizeY - self.ResizeDistancesY[j][1]
x1 = self.ResizeDistancesX[i][0] + self.ResizeDistancesX[i][1]
offsetX += resizeX - self.ResizeDistancesX[i][1]
x1 = self.ResizeDistancesX[len(
self.ResizeDistancesX) - 1][0] + self.ResizeDistancesX[len(self.ResizeDistancesX) - 1][1]
widthResize = self.Image.width() - x1 - 2
y1 = 0
lostX = 0.0
lostY = 0.0
offsetY = 0
for i in range(len(self.ResizeDistancesY)):
self.DrawConstPart(QRect(x1 + 1, y1 + 1, widthResize, self.ResizeDistancesY[i][0] - y1),
QRect(x1 + offsetX, y1 + offsetY, widthResize, self.ResizeDistancesY[i][0] - y1), painter)
y1 = self.ResizeDistancesY[i][0]
resizeY = round(float(self.ResizeDistancesY[i][1]) * factorY)
lostY += resizeY - (float(self.ResizeDistancesY[i][1]) * factorY)
if (fabs(lostY) >= 1.0):
if (lostY < 0):
resizeY += 1
lostY += 1.0
else:
resizeY -= 1
lostY -= 1.0
self.DrawScaledPart(QRect(x1 + 1, y1 + 1, widthResize, self.ResizeDistancesY[i][1]),
QRect(x1 + offsetX, y1 + offsetY, widthResize, resizeY), painter)
y1 = self.ResizeDistancesY[i][0] + self.ResizeDistancesY[i][1]
offsetY += resizeY - self.ResizeDistancesY[i][1]
y1 = self.ResizeDistancesY[len(
self.ResizeDistancesY) - 1][0] + self.ResizeDistancesY[len(self.ResizeDistancesY) - 1][1]
heightResize = self.Image.height() - y1 - 2
x1 = 0
offsetX = 0
for i in range(len(self.ResizeDistancesX)):
self.DrawConstPart(QRect(x1 + 1, y1 + 1, self.ResizeDistancesX[i][0] - x1, heightResize),
QRect(x1 + offsetX, y1 + offsetY, self.ResizeDistancesX[i][0] - x1, heightResize), painter)
x1 = self.ResizeDistancesX[i][0]
resizeX = round(float(self.ResizeDistancesX[i][1]) * factorX)
lostX += resizeX - (float(self.ResizeDistancesX[i][1]) * factorX)
if (fabs(lostX) >= 1.0):
if (lostX < 0):
resizeX += 1
lostX += 1.0
else:
resizeX -= 1
lostX += 1.0
self.DrawScaledPart(QRect(x1 + 1, y1 + 1, self.ResizeDistancesX[i][1], heightResize),
QRect(x1 + offsetX, y1 + offsetY, resizeX, heightResize), painter)
x1 = self.ResizeDistancesX[i][0] + self.ResizeDistancesX[i][1]
offsetX += resizeX - self.ResizeDistancesX[i][1]
x1 = self.ResizeDistancesX[len(
self.ResizeDistancesX) - 1][0] + self.ResizeDistancesX[len(self.ResizeDistancesX) - 1][1]
widthResize = self.Image.width() - x1 - 2
y1 = self.ResizeDistancesY[len(
self.ResizeDistancesY) - 1][0] + self.ResizeDistancesY[len(self.ResizeDistancesY) - 1][1]
heightResize = self.Image.height() - y1 - 2
self.DrawConstPart(QRect(x1 + 1, y1 + 1, widthResize, heightResize),
QRect(x1 + offsetX, y1 + offsetY, widthResize, heightResize), painter)
Useful links
- Learn PyQt: https://pythonbasics.org/pyqt-hello-world/
- Install PyQt: https://pythonbasics.org/install-pyqt/