2

我目前有一个 QScrollArea 定义为:

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)

它非常高兴地嵌套在其他布局/小部件中,按预期调整大小等。

为了为网格列提供标题,我使用了位于滚动区域正上方的另一个 QGridLayout - 这很有效……但看起来有点奇怪,即使样式设置得当,尤其是当按需(垂直)滚动条出现或消失时根据需要,标题不再与网格列正确对齐。这是我所知道的美学问题……但我有点挑剔;)

self.results_grid_layout其他小部件以编程方式添加/删除到其他地方。上面的最后一行我最近刚刚添加,因为我认为使用创建的边距区域很容易,setViewportMargins 的文档状态:

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很有用。边缘空间留空;将小部件放在未使用的区域。

但是我一辈子都无法弄清楚如何真正实现这一目标,而且我的 GoogleFu 今天已经抛弃了我,或者几乎没有关于如何真正实现这一目标的信息/示例。

我的头脑告诉我,我可以只分配一个小部件,由布局(包含任意数量的其他小部件)控制到滚动区域 - 正如我所做的那样。如果我将 QHeaderview 例如添加到网格布局的第 0 行,它只会出现在视口的边距下方并与布局的其余部分一起滚动?还是我错过了一些东西,只是看不到树木的树木?

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)将不胜感激!


编辑:遵循到目前为止给出的建议(我认为),我想出了以下小测试程序来尝试一下:

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()

沿着这些思路的东西是你所指的方法吗?一切都按预期工作,这正是我所追求的,除了在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,一切都排好了。我可能又想多了,或者至少忽略了一些东西……有什么想法吗?

4

2 回答 2

3

我有一个类似的问题,并以不同的方式解决了它。而不是使用一个QScrollArea我使用两个并将下部滚动区域的移动向前移动到顶部。下面的代码所做的是

  1. 它在 QVBoxLayout 中创建了两个 QScrollArea 小部件。
  2. 它禁用顶部 QScrollArea 的滚动条的可见性并为其分配一个固定的高度。
  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的 QScrollArea “转发”到顶部,从而在窗口顶部产生一个固定的标题。

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)

由上述代码产生的窗口。

于 2017-09-29T14:29:14.117 回答
2

你可能会稍微多想一些事情。

您需要做的就是使用滚动区域视口的几何形状和当前边距来计算要放置在边距中的任何小部件的几何形状。

这些小部件的几何形状也需要在滚动区域中更新resizeEvent

如果您查看 的源代码QTableView,我想您会发现它使用这种方法来管理其标题视图(或非常类似的东西)。

编辑

为了处理测试用例中的小问题,我建议您阅读文档中的坐标QRect部分(特别是从第三段开始)。

通过像这样重写您的测试用例,我能够获得更准确的调整大小:

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_())
于 2012-02-21T20:02:45.593 回答