如何将固定标头添加到QScrollArea?

时间:2012-02-21 14:03:52

标签: python header pyqt pyside qscrollarea

我目前有一个由以下人员定义的QScrollArea:

self.results_grid_scrollarea = QScrollArea()
self.results_grid_widget = QWidget()
self.results_grid_layout = QGridLayout()
self.results_grid_layout.setSizeConstraint(QLayout.SetMinAndMaxSize)
self.results_grid_widget.setLayout(self.results_grid_layout)
self.results_grid_scrollarea.setWidgetResizable(True)
self.results_grid_scrollarea.setWidget(self.results_grid_widget)
self.results_grid_scrollarea.setViewportMargins(0,20,0,0)

非常愉快地嵌套在其他布局/窗口小部件中,按预期调整大小等。

要为网格列提供标题,我正在使用另一个位于滚动区域正上方的QGridLayout - 这可以工作......但看起来有点奇怪,即使样式设置得当,尤其是当按需(垂直)滚动条时根据需要显示或消失,标题不再与网格列正确对齐。这是我认识的美学事物......但我有点挑剔;)

其他小部件以编程方式在其他地方添加/删除到self.results_grid_layout。我最近刚刚添加的最后一行,因为我认为使用创建的边距区域很容易,docs用于setViewportMargins状态:

  
    
      

设置滚动区域周围的边距。这对于具有“锁定”行和列的电子表格等应用程序非常有用。边际空间是空白的; 将小部件放在未使用的区域。

    
  

但我不能为我的生活找到如何实现这一点,而且我的GoogleFu今天已经抛弃了我,或者关于如何实现这一目标的信息/示例很少。

我的脑袋告诉我,我只能分配一个小部件,由布局控制(包含任意数量的其他小部件)到滚动区域 - 正如我所做的那样。如果我添加一个QHeaderview作为例如gridlayout的第0行,它将只显示在视口的边缘下方并滚动其余的布局?或者我错过了什么,只是看不到树木的木头?

我只是在学习Python / Qt,所以任何帮助,指针和/或示例(最好使用Python但不是必需的)都将不胜感激!


编辑:按照目前给出的建议(我认为),我想出了以下小测试程序来尝试:

import sys
from PySide.QtCore import *
from PySide.QtGui import *

class MainWindow(QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.setMinimumSize(640, 480)

        self.container_widget = QWidget()
        self.container_layout = QVBoxLayout()
        self.container_widget.setLayout(self.container_layout)
        self.setCentralWidget(self.container_widget)

        self.info_label = QLabel(
            "Here you can see the problem.... I hope!\n"
            "Once the window is resized everything behaves itself.")
        self.info_label.setWordWrap(True)

        self.headings_widget = QWidget()
        self.headings_layout = QGridLayout()
        self.headings_widget.setLayout(self.headings_layout)
        self.headings_layout.setContentsMargins(1,1,0,0)

        self.heading_label1 = QLabel("Column 1")
        self.heading_label1.setContentsMargins(16,0,0,0)
        self.heading_label2 = QLabel("Col 2")
        self.heading_label2.setAlignment(Qt.AlignCenter)
        self.heading_label2.setMaximumWidth(65)
        self.heading_label3 = QLabel("Column 3")
        self.heading_label3.setContentsMargins(8,0,0,0)
        self.headings_layout.addWidget(self.heading_label1,0,0)
        self.headings_layout.addWidget(self.heading_label2,0,1)
        self.headings_layout.addWidget(self.heading_label3,0,2)
        self.headings_widget.setStyleSheet(
            "background: green; border-bottom: 1px solid black;" )

        self.grid_scrollarea = QScrollArea()
        self.grid_widget = QWidget()
        self.grid_layout = QGridLayout()
        self.grid_layout.setSizeConstraint(QLayout.SetMinAndMaxSize)
        self.grid_widget.setLayout(self.grid_layout)
        self.grid_scrollarea.setWidgetResizable(True)
        self.grid_scrollarea.setWidget(self.grid_widget)
        self.grid_scrollarea.setViewportMargins(0,30,0,0)
        self.headings_widget.setParent(self.grid_scrollarea)
        ### Add some linedits to the scrollarea just to test
        rows_to_add = 10
        ## Setting the above to a value greater than will fit in the initial
        ## window will cause the lineedits added below to display correctly,
        ## however - using the 10 above, the lineedits do not expand to fill
        ## the scrollarea's width until you resize the window horizontally.
        ## What's the best way to fix this odd initial behaviour?
        for i in range(rows_to_add):
            col1 = QLineEdit()
            col2 = QLineEdit()
            col2.setMaximumWidth(65)
            col3 = QLineEdit()
            row = self.grid_layout.rowCount()
            self.grid_layout.addWidget(col1,row,0)
            self.grid_layout.addWidget(col2,row,1)
            self.grid_layout.addWidget(col3,row,2)
        ### Define Results group to hold the above sections
        self.test_group = QGroupBox("Results")
        self.test_layout = QVBoxLayout()
        self.test_group.setLayout(self.test_layout)
        self.test_layout.addWidget(self.info_label)
        self.test_layout.addWidget(self.grid_scrollarea)
        ### Add everything to the main layout
        self.container_layout.addWidget(self.test_group)


    def resizeEvent(self, event):
        scrollarea_vpsize = self.grid_scrollarea.viewport().size()
        scrollarea_visible_size = self.grid_scrollarea.rect()
        desired_width = scrollarea_vpsize.width()
        desired_height = scrollarea_visible_size.height()
        desired_height =  desired_height - scrollarea_vpsize.height()
        new_geom = QRect(0,0,desired_width+1,desired_height-1)
        self.headings_widget.setGeometry(new_geom)


def main():
    app = QApplication(sys.argv)
    form = MainWindow()
    form.show()
    app.exec_()

if __name__ == '__main__':
   main()

这些方面的内容是您指向的方法吗?一切都按预期工作,正如我所追求的那样,除了用户调整窗口大小之前的一些奇怪的初始行为,一旦调整大小,所有内容都排成一行并且很好。 我可能会再次过度思考或者至少忽视某些事情......任何想法?

2 个答案:

答案 0 :(得分:1)

你可能会略微过度思考。

您需要做的就是使用scrollarea视口的几何和当前边距来计算要放在边距中的任何小部件的几何。

这些小部件的几何图形也需要在滚动区域的resizeEvent中更新。

如果您查看QTableView的源代码,我认为您会发现它使用此方法来管理其标头视图(或类似的东西)。

修改

为了处理测试用例中的小调整大小问题,我建议您阅读QRect文档中的Coordinates部分(特别是第三段开始)。

通过重写这样的测试用例,我能够更准确地调整大小:

import sys
from PySide.QtCore import *
from PySide.QtGui import *

class MainWindow(QMainWindow):
    def __init__(self, parent=None):
        super(MainWindow, self).__init__(parent)
        self.setMinimumSize(640, 480)
        self.container_widget = QWidget()
        self.container_layout = QVBoxLayout()
        self.container_widget.setLayout(self.container_layout)
        self.setCentralWidget(self.container_widget)
        self.grid_scrollarea = ScrollArea(self)
        self.test_group = QGroupBox("Results")
        self.test_layout = QVBoxLayout()
        self.test_group.setLayout(self.test_layout)
        self.test_layout.addWidget(self.grid_scrollarea)
        self.container_layout.addWidget(self.test_group)

class ScrollArea(QScrollArea):
    def __init__(self, parent=None):
        QScrollArea.__init__(self, parent)
        self.grid_widget = QWidget()
        self.grid_layout = QGridLayout()
        self.grid_widget.setLayout(self.grid_layout)
        self.setWidgetResizable(True)
        self.setWidget(self.grid_widget)
        # save the margin values
        self.margins = QMargins(0, 30, 0, 0)
        self.setViewportMargins(self.margins)
        self.headings_widget = QWidget(self)
        self.headings_layout = QGridLayout()
        self.headings_widget.setLayout(self.headings_layout)
        self.headings_layout.setContentsMargins(1,1,0,0)
        self.heading_label1 = QLabel("Column 1")
        self.heading_label1.setContentsMargins(16,0,0,0)
        self.heading_label2 = QLabel("Col 2")
        self.heading_label2.setAlignment(Qt.AlignCenter)
        self.heading_label2.setMaximumWidth(65)
        self.heading_label3 = QLabel("Column 3")
        self.heading_label3.setContentsMargins(8,0,0,0)
        self.headings_layout.addWidget(self.heading_label1,0,0)
        self.headings_layout.addWidget(self.heading_label2,0,1)
        self.headings_layout.addWidget(self.heading_label3,0,2)
        self.headings_widget.setStyleSheet(
            "background: green; border-bottom: 1px solid black;" )
        rows_to_add = 10
        for i in range(rows_to_add):
            col1 = QLineEdit()
            col2 = QLineEdit()
            col2.setMaximumWidth(65)
            col3 = QLineEdit()
            row = self.grid_layout.rowCount()
            self.grid_layout.addWidget(col1,row,0)
            self.grid_layout.addWidget(col2,row,1)
            self.grid_layout.addWidget(col3,row,2)

    def resizeEvent(self, event):
        rect = self.viewport().geometry()
        self.headings_widget.setGeometry(
            rect.x(), rect.y() - self.margins.top(),
            rect.width() - 1, self.margins.top())
        QScrollArea.resizeEvent(self, event)

if __name__ == '__main__':

    app = QApplication(sys.argv)
    form = MainWindow()
    form.show()
    sys.exit(app.exec_())

答案 1 :(得分:1)

我遇到了类似的问题并且解决了一些不同的问题。而不是使用一个QScrollArea我使用两个并将下滚动区域的移动向前移动到顶部。以下代码的作用是

  1. 它在QVBoxLayout中创建了两个QScrollArea小部件。
  2. 它会禁用顶部QScrollArea滚动条的可见性,并为其指定固定高度。
  3. 使用较低QScrollArea的水平滚动条的valueChanged信号,可以将水平滚动条值从较低QScrollArea“转发”到顶部,从而在窗口顶部生成固定标题
  4. class MainWindow(QMainWindow):
        def __init__(self, parent=None):
            super(MainWindow, self).__init__(parent)
    
            widget = QWidget()
            self.setCentralWidget(widget)
    
            vLayout = QVBoxLayout()
            widget.setLayout(vLayout)
    
            # TOP
            scrollAreaTop = QScrollArea()
            scrollAreaTop.setWidgetResizable(True)
            scrollAreaTop.setFixedHeight(30)
            scrollAreaTop.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
            scrollAreaTop.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
            scrollAreaTop.setWidget(QLabel(" ".join([str(i) for i in range(100)])))
    
            # BOTTOM
            scrollAreaBottom = QScrollArea()
            scrollAreaBottom.setWidgetResizable(True)
            scrollAreaBottom.setWidget(QLabel("\n".join([" ".join([str(i) for i in range(100)]) for _ in range(10)])))
            scrollAreaBottom.horizontalScrollBar().valueChanged.connect(lambda value: scrollAreaTop.horizontalScrollBar().setValue(value))
    
            vLayout.addWidget(scrollAreaTop)
            vLayout.addWidget(scrollAreaBottom)
    

    Window resulting from above code.