PySide.QtGui.QGraphicsLinearLayout class provides a horizontal or vertical layout for managing widgets in Graphics View.
The default orientation for a linear layout is Qt.Horizontal . You can choose a vertical orientation either by calling PySide.QtGui.QGraphicsLinearLayout.setOrientation() , or by passing Qt.Vertical to PySide.QtGui.QGraphicsLinearLayout ‘s constructor.
The most common way to use PySide.QtGui.QGraphicsLinearLayout is to construct an object on the heap with no parent, add widgets and layouts by calling PySide.QtGui.QGraphicsLinearLayout.addItem() , and finally assign the layout to a widget by calling QGraphicsWidget.setLayout() .
scene = QGraphicsScene()
textEdit = scene.addWidget(QTextEdit())
pushButton = scene.addWidget(QPushButton())
layout = QGraphicsLinearLayout()
layout.addItem(textEdit)
layout.addItem(pushButton)
form = QGraphicsWidget()
form.setLayout(layout)
scene.addItem(form)
You can add widgets, layouts, stretches ( PySide.QtGui.QGraphicsLinearLayout.addStretch() , PySide.QtGui.QGraphicsLinearLayout.insertStretch() or PySide.QtGui.QGraphicsLinearLayout.setStretchFactor() ), and spacings ( PySide.QtGui.QGraphicsLinearLayout.setItemSpacing() ) to a linear layout. The layout takes ownership of the items. In some cases when the layout item also inherits from PySide.QtGui.QGraphicsItem (譬如 PySide.QtGui.QGraphicsWidget ) there will be a ambiguity in ownership because the layout item belongs to two ownership hierarchies. See the documentation of QGraphicsLayoutItem.setOwnedByLayout() how to handle this. You can access each item in the layout by calling PySide.QtGui.QGraphicsLinearLayout.count() and PySide.QtGui.QGraphicsLinearLayout.itemAt() 。调用 PySide.QtGui.QGraphicsLinearLayout.removeAt() or PySide.QtGui.QGraphicsLinearLayout.removeItem() will remove an item from the layout, without destroying it.
You can assign a stretch factor to each item to control how much space it will get compared to the other items. By default, two identical widgets arranged in a linear layout will have the same size, but if the first widget has a stretch factor of 1 and the second widget has a stretch factor of 2, the first widget will get 1/3 of the available space, and the second will get 2/3.
PySide.QtGui.QGraphicsLinearLayout calculates the distribution of sizes by adding up the stretch factors of all items, and then dividing the available space accordingly. The default stretch factor is 0 for all items; a factor of 0 means the item does not have any defined stretch factor; effectively this is the same as setting the stretch factor to 1. The stretch factor only applies to the available space in the lengthwise direction of the layout (following its orientation). If you want to control both the item's horizontal and vertical stretch, you can use PySide.QtGui.QGraphicsGridLayout 代替。
PySide.QtGui.QGraphicsLinearLayout 非常类似 PySide.QtGui.QVBoxLayout and PySide.QtGui.QHBoxLayout , but in contrast to these classes, it is used to manage PySide.QtGui.QGraphicsWidget and PySide.QtGui.QGraphicsLayout 而不是 PySide.QtGui.QWidget and PySide.QtGui.QLayout .
| 参数： |
|
|---|
构造 PySide.QtGui.QGraphicsLinearLayout instance using Qt.Horizontal orientation. parent 会被传递给 PySide.QtGui.QGraphicsLayout ‘s constructor.
| 参数： | item – PySide.QtGui.QGraphicsLayoutItem |
|---|
This convenience function is equivalent to calling insertItem(-1, item ).
| 参数： | stretch – PySide.QtCore.int |
|---|
This convenience function is equivalent to calling insertStretch(-1, stretch ).
| 参数： | item – PySide.QtGui.QGraphicsLayoutItem |
|---|---|
| 返回类型： | PySide.QtCore.Qt.Alignment |
返回对齐方式为 item . The default alignment is Qt.AlignTop | Qt.AlignLeft .
The alignment decides how the item is positioned within its assigned space in the case where there's more space available in the layout than the widgets can occupy.
| 参数： | indent – PySide.QtCore.int |
|---|
| 参数： |
|
|---|
插入 item into the layout at index , or before any item that is currently at index .
另请参阅
PySide.QtGui.QGraphicsLinearLayout.addItem() PySide.QtGui.QGraphicsLinearLayout.itemAt() PySide.QtGui.QGraphicsLinearLayout.insertStretch() PySide.QtGui.QGraphicsLinearLayout.setItemSpacing()
| 参数： |
|
|---|
Inserts a stretch of stretch at index , or before any item that is currently at index .
| 参数： | index – PySide.QtCore.int |
|---|---|
| 返回类型： | PySide.QtCore.qreal |
Returns the spacing after item at index .
| 返回类型： | PySide.QtCore.Qt.Orientation |
|---|
Returns the layout orientation.
| 参数： | item – PySide.QtGui.QGraphicsLayoutItem |
|---|
移除 item from the layout without destroying it. Ownership of item is transferred to the caller.
另请参阅
PySide.QtGui.QGraphicsLinearLayout.removeAt() PySide.QtGui.QGraphicsLinearLayout.insertItem()
| 参数： |
|
|---|
| 参数： |
|
|---|
Sets the spacing after item at index to spacing .
| 参数： | orientation – PySide.QtCore.Qt.Orientation |
|---|
| 参数： | spacing – PySide.QtCore.qreal |
|---|
Sets the layout's spacing to spacing . Spacing refers to the vertical and horizontal distances between items.
| 参数： |
|
|---|
设置拉伸因子为 item to stretch . If an item's stretch factor changes, this function will invalidate the layout.
设置 stretch to 0 removes the stretch factor from the item, and is effectively equivalent to setting stretch to 1.
| 返回类型： | PySide.QtCore.qreal |
|---|
Returns the layout's spacing. Spacing refers to the vertical and horizontal distances between items.
| 参数： | item – PySide.QtGui.QGraphicsLayoutItem |
|---|---|
| 返回类型： | PySide.QtCore.int |
Returns the stretch factor for item . The default stretch factor is 0, meaning that the item has no assigned stretch factor.