qtextedit - resize to fit

问题

I have a QTextEdit which act as "displayer" (editable to false). The text it displays is wordwrapped. Now I do wish to set the height of this textbox so that the text fits exactly (while also respecting a maximum height).

Basically the widget (in the same vertical layout) below the layout should get as much space as possible.

How can this be achieved most easily?

回答1:

I found a pretty stable, easy solution using QFontMetrics!

from PyQt4 import QtGui

text = ("The answer is QFontMetrics\n."
        "\n"
        "The layout system messes with the width that QTextEdit thinks it\n"
        "needs to be.  Instead, let's ignore the GUI entirely by using\n"
        "QFontMetrics.  This can tell us the size of our text\n"
        "given a certain font, regardless of the GUI it which that text will be displayed.")

app = QtGui.QApplication([])

textEdit = QtGui.QPlainTextEdit()
textEdit.setPlainText(text)
textEdit.setLineWrapMode(True)      # not necessary, but proves the example

font = textEdit.document().defaultFont()    # or another font if you change it
fontMetrics = QtGui.QFontMetrics(font)      # a QFontMetrics based on our font
textSize = fontMetrics.size(0, text)

textWidth = textSize.width() + 30       # constant may need to be tweaked
textHeight = textSize.height() + 30     # constant may need to be tweaked

textEdit.setMinimumSize(textWidth, textHeight)  # good if you want to insert this into a layout
textEdit.resize(textWidth, textHeight)          # good if you want this to be standalone

textEdit.show()

app.exec_()

(Forgive me, I know your question is about C++, and I'm using Python, but in Qt they're pretty much the same thing anyway).

回答2:

Unless there is something particular to the capabilities of a QTextEdit that you need, a QLabel with word wrap turned on will do exactly what you want.

回答3:

Current size of the underlying text can be available via

QTextEdit::document()->size();

and I believe that using this we could resize the widget accordingly.

#include <QTextEdit>
#include <QApplication>
#include <iostream>
using namespace std;

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QTextEdit te ("blah blah blah blah blah blah blah blah blah blah blah blah");
    te.show();
    cout << te.document()->size().height() << endl;
    cout << te.document()->size().width() << endl;
    cout <<  te.size().height() << endl;
    cout <<  te.size().width() << endl;
// and you can resize then how do you like, e.g. :
    te.resize(te.document()->size().width(), 
              te.document()->size().height() + 10);
    return a.exec();    
}

回答4:

Speaking of Python, I actually found .setFixedWidth( your_width_integer ) and .setFixedSize( your_width, your_height ) quite useful. Not sure if C has similar widget attributes.

回答5:

In my case, I put my QLabel inside a QScrollArea. And if you are keen, you combine both and make your own widget.

来源：https://stackoverflow.com/questions/9506586/qtextedit-resize-to-fit

标签

c++

qtextedit