qt grow-only size policy

Question

I have QLabel and this width shrink to content size. How can I set size policy to grow-only policy? for example, I set text to "12345" and QLabel should grow to minimal size to show this content, but when I set "12" this wouldnt shrink and stay old size.

Answer 1

Well, unless you don't need to use the space you want to recover for others widgets, you can use a QtGui.QSpacerItem; see QSpacerItem Class Reference.

You can set the size policy to the spacer item.

Note: This gets done automatically when you're using QtDesigner.

In QtDesigner, it should look like this:

The label has a cyan background for ilustrative purposes.

Here, you have some code sample:

Warning: the code has been written in Python. I don't know your lenguage preferences. But the interface is pretty much the same. Goog luck.

import PyQt4.QtGui as gui
import PyQt4.QtCore as core

import sys

if __name__ == "__main__":

    app =  gui.QApplication(sys.argv)

    widget = gui.QWidget(None)
    label = gui.QLabel(widget)

    label.setStyleSheet("background-color: cyan;")

    label.setMinimumWidth(10)
    label.setText("Write some text above")

    text = gui.QLineEdit(widget)

    layout = gui.QVBoxLayout(widget)

    hlayout = gui.QHBoxLayout(widget)   # This layout will contains
                                        # the label and a sacer item.

    layout.addWidget(text)

    hlayout.addWidget(label)            # Add the label.        
    # Create the spacer.
    spacerItem = gui.QSpacerItem(40, 20, gui.QSizePolicy.Expanding, gui.QSizePolicy.Minimum)
    hlayout.addItem(spacerItem)         # Add the spacer.
    layout.addItem(hlayout)


    # Slot for change the text of the label. 
    @core.pyqtSlot()
    def on_textChanged():
        label.setText(text.text())

    text.textChanged.connect(on_textChanged)

    widget.show()
    sys.exit(app.exec_())