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PODelete A Row From QGridLayout
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  1. PODelete A Row From QGridLayout
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    copied!<p>All, I am maintaining a <code>QGridLayout</code> of <code>QLabels</code> which show the coefficients of a polynomial. I represent my polynomial using <code>QList&lt;double&gt;</code>.</p> <p>Each time I update my coefficients, I update my labels. When changing the size of the list, my method <strong>does not</strong> works well. <code>QGridLayout::rowCount()</code> doesn't update correctly. I am wondering if there's a way to remove rows from a QGridLayout.</p> <hr> <p>Code follows, updating the <code>QGridLayout</code> size with more (or less) <code>QLabels</code></p> <pre><code>int count = coefficients-&gt;count(); //coefficients is a QList&lt;double&gt; * if(count != (m_informational-&gt;rowCount() - 1)) //m_information is a QGridLayout { SetFitMethod(0); for(int i = 0; i &lt; count; ++i) { QLabel * new_coeff = new QLabel(this); new_coeff-&gt;setAlignment(Qt::AlignRight); m_informational-&gt;addWidget(new_coeff, i+1, 0); QLabel * param = new QLabel(this); param-&gt;setAlignment(Qt::AlignLeft); param-&gt;setText(QString("&lt;b&gt;&lt;i&gt;x&lt;/i&gt;&lt;sup&gt;%2&lt;/sup&gt;&lt;/b&gt;").arg(count-i-1)); m_informational-&gt;addWidget(param, i+1, 1); QSpacerItem * space = new QSpacerItem(0,0,QSizePolicy::Expanding); m_informational-&gt;addItem(space, i+1, 1); } m_informational-&gt;setColumnStretch(0, 3); m_informational-&gt;setColumnStretch(1, 1); m_informational-&gt;setColumnStretch(2, 1); } </code></pre> <p>The SetFitMethod (it's an initial mockup)</p> <pre><code>void SetFitMethod(int method) { ClearInformational(); switch(method) { case 0: //Polynomial fit QLabel * title = new QLabel(this); title-&gt;setText("&lt;b&gt; &lt;u&gt; Coefficients &lt;/u&gt; &lt;/b&gt;"); title-&gt;setAlignment(Qt::AlignHCenter); m_informational-&gt;addWidget(title,0,0,1,3, Qt::AlignHCenter); } } </code></pre> <p>The Clearing Method:</p> <pre><code>void ClearInformational() { while(m_informational-&gt;count()) { QLayoutItem * cur_item = m_informational-&gt;takeAt(0); if(cur_item-&gt;widget()) delete cur_item-&gt;widget(); delete cur_item; } } </code></pre>
 

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