QGraphicsLinearLayout

Synopsis

Functions

• def addItem (item)
• def addStretch ([stretch=1])
• def alignment (item)
• def dump ([indent=0])
• def insertItem (index, item)
• def insertStretch (index[, stretch=1])
• def itemSpacing (index)
• def orientation ()
• def removeItem (item)
• def setAlignment (item, alignment)
• def setItemSpacing (index, spacing)
• def setOrientation (orientation)
• def setSpacing (spacing)
• def setStretchFactor (item, stretch)
• def spacing ()
• def stretchFactor (item)

Detailed Description

The 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 (such as 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() . Calling PySide.QtGui.QGraphicsLinearLayout.removeAt() or PySide.QtGui.QGraphicsLinearLayout.removeItem() will remove an item from the layout, without destroying it.

Size Hints and Size Policies in QGraphicsLinearLayout

PySide.QtGui.QGraphicsLinearLayout respects each item’s size hints and size policies, and when the layout contains more space than the items can fill, each item is arranged according to the layout’s alignment for that item. You can set an alignment for each item by calling PySide.QtGui.QGraphicsLinearLayout.setAlignment() , and check the alignment for any item by calling PySide.QtGui.QGraphicsLinearLayout.alignment() . By default, items are aligned to the top left.

Spacing within QGraphicsLinearLayout

Between the items, the layout distributes some space. The actual amount of space depends on the managed widget’s current style, but the common spacing is 4. You can also set your own spacing by calling PySide.QtGui.QGraphicsLinearLayout.setSpacing() , and get the current spacing value by calling PySide.QtGui.QGraphicsLinearLayout.spacing() . If you want to configure individual spacing for your items, you can call PySide.QtGui.QGraphicsLinearLayout.setItemSpacing() .

Stretch Factor in QGraphicsLinearLayout

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 instead.

QGraphicsLinearLayout Compared to Other Layouts

PySide.QtGui.QGraphicsLinearLayout is very similar to 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 instead of PySide.QtGui.QWidget and PySide.QtGui.QLayout .

See also

PySide.QtGui.QGraphicsGridLayout PySide.QtGui.QGraphicsWidget

class PySide.QtGui.QGraphicsLinearLayout([parent=None])

class PySide.QtGui.QGraphicsLinearLayout(orientation[, parent=None])

Parameters:

• parent – PySide.QtGui.QGraphicsLayoutItem
• orientation – PySide.QtCore.Qt.Orientation

Constructs a PySide.QtGui.QGraphicsLinearLayout instance using Qt.Horizontal orientation. parent is passed to PySide.QtGui.QGraphicsLayout ‘s constructor.

PySide.QtGui.QGraphicsLinearLayout.addItem(item)

Parameters:item – PySide.QtGui.QGraphicsLayoutItem

This convenience function is equivalent to calling insertItem(-1, item ).

PySide.QtGui.QGraphicsLinearLayout.addStretch([stretch=1])

Parameters:stretch – PySide.QtCore.int

This convenience function is equivalent to calling insertStretch(-1, stretch ).

PySide.QtGui.QGraphicsLinearLayout.alignment(item)

Parameters:item – PySide.QtGui.QGraphicsLayoutItem Return type:PySide.QtCore.Qt.Alignment

Returns the alignment for 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.

See also

PySide.QtGui.QGraphicsLinearLayout.setAlignment()

PySide.QtGui.QGraphicsLinearLayout.dump([indent=0])

Parameters:indent – PySide.QtCore.int

PySide.QtGui.QGraphicsLinearLayout.insertItem(index, item)

Parameters:

• index – PySide.QtCore.int
• item – PySide.QtGui.QGraphicsLayoutItem

Inserts item into the layout at index , or before any item that is currently at index .

See also

PySide.QtGui.QGraphicsLinearLayout.addItem() PySide.QtGui.QGraphicsLinearLayout.itemAt() PySide.QtGui.QGraphicsLinearLayout.insertStretch() PySide.QtGui.QGraphicsLinearLayout.setItemSpacing()

PySide.QtGui.QGraphicsLinearLayout.insertStretch(index[, stretch=1])

Parameters:

• index – PySide.QtCore.int
• stretch – PySide.QtCore.int

Inserts a stretch of stretch at index , or before any item that is currently at index .

See also

PySide.QtGui.QGraphicsLinearLayout.addStretch() PySide.QtGui.QGraphicsLinearLayout.setStretchFactor() PySide.QtGui.QGraphicsLinearLayout.setItemSpacing() PySide.QtGui.QGraphicsLinearLayout.insertItem()

PySide.QtGui.QGraphicsLinearLayout.itemSpacing(index)

Parameters:index – PySide.QtCore.int Return type:PySide.QtCore.qreal

Returns the spacing after item at index .

See also

PySide.QtGui.QGraphicsLinearLayout.setItemSpacing()

PySide.QtGui.QGraphicsLinearLayout.orientation()

Return type:PySide.QtCore.Qt.Orientation

Returns the layout orientation.

See also

PySide.QtGui.QGraphicsLinearLayout.setOrientation()

PySide.QtGui.QGraphicsLinearLayout.removeItem(item)

Parameters:item – PySide.QtGui.QGraphicsLayoutItem

Removes item from the layout without destroying it. Ownership of item is transferred to the caller.

See also

PySide.QtGui.QGraphicsLinearLayout.removeAt() PySide.QtGui.QGraphicsLinearLayout.insertItem()

PySide.QtGui.QGraphicsLinearLayout.setAlignment(item, alignment)

Parameters:

• item – PySide.QtGui.QGraphicsLayoutItem
• alignment – PySide.QtCore.Qt.Alignment

PySide.QtGui.QGraphicsLinearLayout.setItemSpacing(index, spacing)

Parameters:

• index – PySide.QtCore.int
• spacing – PySide.QtCore.qreal

Sets the spacing after item at index to spacing .

See also

PySide.QtGui.QGraphicsLinearLayout.itemSpacing()

PySide.QtGui.QGraphicsLinearLayout.setOrientation(orientation)

Parameters:orientation – PySide.QtCore.Qt.Orientation

PySide.QtGui.QGraphicsLinearLayout.setSpacing(spacing)

Parameters:spacing – PySide.QtCore.qreal

Sets the layout’s spacing to spacing . Spacing refers to the vertical and horizontal distances between items.

See also

PySide.QtGui.QGraphicsLinearLayout.spacing() PySide.QtGui.QGraphicsLinearLayout.setItemSpacing() PySide.QtGui.QGraphicsLinearLayout.setStretchFactor() QGraphicsGridLayout.setSpacing()

PySide.QtGui.QGraphicsLinearLayout.setStretchFactor(item, stretch)

Parameters:

• item – PySide.QtGui.QGraphicsLayoutItem
• stretch – PySide.QtCore.int

Sets the stretch factor for item to stretch . If an item’s stretch factor changes, this function will invalidate the layout.

Setting stretch to 0 removes the stretch factor from the item, and is effectively equivalent to setting stretch to 1.

See also

PySide.QtGui.QGraphicsLinearLayout.stretchFactor()

PySide.QtGui.QGraphicsLinearLayout.spacing()

Return type:PySide.QtCore.qreal

Returns the layout’s spacing. Spacing refers to the vertical and horizontal distances between items.

See also

PySide.QtGui.QGraphicsLinearLayout.setSpacing()

PySide.QtGui.QGraphicsLinearLayout.stretchFactor(item)

Parameters:item – PySide.QtGui.QGraphicsLayoutItem Return type:PySide.QtCore.int

Returns the stretch factor for item . The default stretch factor is 0, meaning that the item has no assigned stretch factor.

See also

PySide.QtGui.QGraphicsLinearLayout.setStretchFactor()