I am creating a QTabWidget that has a number of tabs and each tab contains a different number of push buttons. Because some of these tabs may include many push buttons, I would like to make each tab scrollable.
I have an implementation that sort of works except no matter what I try I can't get the darn QTabWidget to be of a particular vertical size - it always wants to size itself based on the maximum height used by one of its pages. I've tried changing size policies, layout strategies and nothing works.
Here is exact widget structure I am using:
QFrame
QSplitter
QTabWidget
QFrame
I populate the QTabWidget with QWidget instances that serve as pages. These instances are wrapped around with a QScrollArea and use a QGridLayout so that I can populate the tab with push buttons in a grid.
Here is the actual code that populates the tab widget:
for (const std::string &tabName : tabs) {
// Grid layout for each tab
QGridLayout *gridLayout = new QGridLayout();
// The tab widget itself
QWidget *page = new QWidget(tabWidget);
page->setLayout(gridLayout);
// Wrap tab with a scroll area so that it's scrollable when the tab widget
// is resized to be smaller than the page size
QScrollArea *scrollArea = new QScrollArea(tabWidget);
scrollArea->setWidgetResizable(true);
scrollArea->setWidget(page);
tabWidget->addTab(scrollArea, tabName.c_str());
// Populate tab with push buttons
const std::vector<std::string> &buttons = GetButtons(tabName);
for (const std::string &buttonName : buttons) {
QPushButton *button = new QPushButton(buttonName.c_str());
button->setSizePolicy(QSizePolicy(QSizePolicy::Fixed, QSizePolicy::Fixed));
QSize buttonSize(130, 20);
button->setFixedSize(buttonSize); // <=== this does work
int row = i / numColumns;
int col = i % numColumns;
gridLayout->addWidget(button, row, col, Qt::AlignLeft | Qt::AlignTop);
}
}
// This does not work
const int fixedVerticalSize = 120;
tabWidget->resize(tabWidget->size().width(), fixedVerticalSize);
BTW, I am using Qt 5.0.2 on Mac OS X 10.8.2.
Related
I've created a a widget in which I've placed two buttons using a layout and placed it inside a table widget's cell. The thing is that I'm changing the size of the table and I want to shift the placement of the widget without deleting them and re-initializing them from the beginning because I already assigned them actions on click (I think that the application would crash in this situation)
Code:
btn = new QPushButton[horzHeaders.size()];
btn[j].setParent(ui->tableWidget);
btn[j].setIcon(QIcon("./save.png"));
btn[j].setVisible(true);
btn_Load = new QPushButton[horzHeaders.size()];
btn_Load[j].setParent(ui->tableWidget);
btn_Load[j].setIcon(QIcon("./upload.png"));
btn_Load[j].setVisible(true);
lay = new QHBoxLayout[horzHeaders.size()];
lay[j].addWidget(&btn[j]);
lay[j].addWidget(&btn_Load[j]);
QWidget *w = new QWidget[horzHeaders.size()];
w[j].setLayout(&lay[j]);
ui->tableWidget->setCellWidget(j,vertHeaders.size() - 1, &w[j]);
You can add and remove widgets from a layout anytime you want
QWidget *widget = new QWidget();
QPushButton *button = new QPushButton();
QHBoxLayout *Hbox = new QHBoxLayout();
QVBoxLayout *Vbox= new QVBoxLayout();
Hbox->addWidget(button);
// use it till the window is resized
//and then check with an if-statement if the window is resized or not
Hbox->removeWidget(button); // remove from the button from layout
layout()->removeAt(widget); //remove the widget's current layout
Vbox->addWidget(button); // add button widget to vertical layout
widget->setLayout(Vbox); // Give it a new layout
widget->setLayout(Vbox);
If this didn't answer your question then ask in the comments.
A qDockWidget containing a qCustomPlot always starts with zero height. I am able to catch the qDockWidget resize event and change the qCustomPlot geometry using these answers, but the qCustomPlot is always hidden until it is manually stretched. Should this happen automatically, or do I need to calculate and set the dock height at startup?
This sample code creates a new qCustomPlot widget, places it in a layout, places that layout in another widget, and sets it to the dock. I have also tried placing the qCustomPlot widget directly into the dock. qCustomPlot setGeometry, setMinimumSize, and setSizePolicy seem to have no effect on the dock height.
#include <QMainWindow>
#include "qcustomplot.h"
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(){
QCustomPlot *m_customPlot;
QDockWidget *dock;
resize(1200, 600);
//create the plot
QWidget *plot_frame_temp= new QWidget();
plot_frame_temp->setSizePolicy(QSizePolicy::MinimumExpanding,QSizePolicy::MinimumExpanding);
m_customPlot = new QCustomPlot(plot_frame_temp);
m_customPlot->axisRect()->setupFullAxesBox(true);
m_customPlot->setBackground(Qt::black);
//size and margin settings
m_customPlot->setGeometry(QRect(0, 0, 500, 400));
m_customPlot->axisRect()->setMinimumSize(500,400);
m_customPlot->axisRect()->setAutoMargins(QCP::msLeft|QCP::msBottom|QCP::msRight|QCP::msTop);
// zoom and drag only on horrizontal axis
m_customPlot->axisRect()->setRangeZoomAxes(m_customPlot->xAxis,nullptr);
m_customPlot->axisRect()->setRangeDragAxes(m_customPlot->xAxis,nullptr);
//setup the top axis and labels
m_customPlot->xAxis->setVisible(false);
m_customPlot->xAxis2->setVisible(true);
m_customPlot->xAxis2->setTicks(true);
m_customPlot->xAxis2->setTickLabels(true);
m_customPlot->xAxis2->setTickPen(QColor(136, 136, 136));
m_customPlot->xAxis2->setTickLength(0,10);
m_customPlot->xAxis2->setTickLabelColor(QColor(136, 136, 136));
m_customPlot->xAxis2->setSubTickPen(Qt::NoPen);
m_customPlot->xAxis2->setBasePen(Qt::NoPen);
QFont font;
font.setStyleStrategy(QFont::PreferOutline);
m_customPlot->xAxis2->setTickLabelFont(font);
//setup the left axis and hide
m_customPlot->yAxis->setVisible(false);
m_customPlot->yAxis->setRangeReversed(true);
m_customPlot->yAxis2->setVisible(false);
//first graph
m_customPlot->addGraph();
m_customPlot->graph()->setPen(QPen(QColor(165, 165, 165)));
m_customPlot->graph()->setLineStyle((QCPGraph::lsStepLeft));
//second graph
m_customPlot->addGraph();
m_customPlot->graph()->setPen(QPen(QColor(165, 165, 165)));
m_customPlot->graph()->setLineStyle((QCPGraph::lsStepLeft));
// make some data
QVector<double> x(500), y0(500), y1(500);
for (int i=0; i<500; ++i)
{
x[i] = i;
y0[i] = (rand() % 2 + 0.2)/2;
y1[i] = (rand() % 2 + 1.4)/2;
}
//add data to graph
m_customPlot->graph(0)->setData(x, y0);
m_customPlot->graph(1)->setData(x, y1);
// set some options
m_customPlot->setNotAntialiasedElements(QCP::aeAll);
m_customPlot->setInteractions(QCP::iRangeDrag | QCP::iRangeZoom);
//add plot widget to layout
QHBoxLayout *laLayout = new QHBoxLayout();
laLayout->addWidget(plot_frame_temp);
//add layout to another widget
QWidget *laWidget=new QWidget();
laWidget->setLayout(laLayout);
//add second widget to dock
dock = new QDockWidget(tr("qcustomplot"), this);
dock->setAllowedAreas(Qt::TopDockWidgetArea | Qt::BottomDockWidgetArea);
dock->setWidget(laWidget);
addDockWidget(Qt::BottomDockWidgetArea, dock);
QWidget *centralWidget=new QWidget();
setCentralWidget(centralWidget);
}
};
Here is a minimum example done directly in mainwindow.h. A dock with a central widget and a QDockWidget with a qCustomPlot. I am using the compiled DLL version of qCustomPlot
Image: dock starts with zero height:
Initially the dock looks like this. The plot is hidden and the dock is claiming no height in an otherwise empty layout.
Image: dock stretched to show the plot
The plot is visible when the user stretches the dock.
I strongly suspect there is a way for the dock to adjust to the height of the qCustomPlot automatically. I can set the dock height from code, but that seems like a hack.
The most direct approach to solve your issue might be to define a minimum size for your QCustomPlot Widget. This can easily achieved with the following reduced example. Actually, the problems has nothing to do with QCustomPlot at all. It could have been any kind of widget with minimum size (0,0).
#include <QMainWindow>
#include "qcustomplot.h"
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(){
auto m_customPlot = new QCustomPlot();
m_customPlot->axisRect()->setupFullAxesBox(true);
auto dock = new QDockWidget(tr("qcustomplot"), this);
dock->setAllowedAreas(Qt::TopDockWidgetArea | Qt::BottomDockWidgetArea);
dock->setWidget(m_customPlot);
m_customPlot->setMinimumSize(QSize(500,500));
dock->setMinimumSize(m_customPlot->minimumSize());
addDockWidget(Qt::DockWidgetArea::BottomDockWidgetArea, dock);
setCentralWidget(new QWidget);
}
};
A better solution might to save and to restore the geometry of your dock widget configuration in the registry. This leaves the user with just the dock widget configuration that he finds desirable.
void MainWindow::closeEvent(QCloseEvent *event)
{
QSettings settings("MyCompany", "MyApp");
settings.setValue("geometry", saveGeometry());
QMainWindow::closeEvent(event);
}
QSettings settings("MyCompany", "MyApp");
dock->restoreGeometry(settings.value("myWidget/geometry").toByteArray());
I pragrammaticaly create a QTreeWidget.
Then I pragrammaticaly add some items.
Then I add two QLabel widgets to two items (QTreeWidgetItem) by
myTree->setItemWidget(item1, 0, myLabel1);
myTree->setItemWidget(item2, 0, myLabel2);
And then I try to resize the row of the item pragrammaticaly.
If I use an
item1->setSizeHint(0, QSize(myWidth, myHeight) );
the row chaged. But myLabel1 is not.
If I use an
item1->setSizeHint(0, QSize(myWidth, myHeight) );
myLabel->resize(myWidth, myHeight);
everething is ok but the row of myLabel2 mis adjusting to label by position.
Can I do something to auto-adjusting a widget (by size and position) to a cell of QTreeWidget?
P.S. After any resizing of tree (resize by width or expand/collapse node) widgets updates correctly.
In view of the fact that autofit start after resizing QTreeWidget, there is some method inside that resize widgets in cells.
So I opened QTreeWidget description (https://doc.qt.io/qt-5/qtreewidget.html) and red all of Public Functions and Public Slots. When I did not find any useful function I looked at a parent class (QTreeView). And found
myTree->resizeColumnToContent(0);
Call resizeColumnToContent after resizing any row in a QTreeWidget and widgets will be always fit to cells.
P.S. I am the OP.
you can try adding/updating a widget as an item, for example:
QWidget* wdg = new QWidget;
QPushButton* btIcon = new QPushButton();
QLabel* lb = new QLabel();
QHBoxLayout* layout = new QHBoxLayout(wdg);
layout->addWidget(btIcon);
layout->addWidget(lb);
layout->setAlignment( Qt::AlignCenter );
wdg->setLayout(layout);
myTree->setItemWidget(item1, 0, wdg);
Or just fill the tree with widgets
Making my way up the Qt learning curve, I've seen many questions about dynamic layouts but the solutions aren't working for me or I don't quite understand them.
Reference questions:: Qt Scroll Area does not add in scroll bars, How can i make widgets overflow to make a scrollbar appear in Qt?
Question:: I want to have a dynamic layout of a set of widgets within a QScrollArea. I've been able to do this manually in Qt Creator and now I am trying to do it through code.
How do I prevent the widgets from stretching/force the area to scroll?
How do I have the added widgets start from the top? I have a vertical spacer in my QVBoxLayout but that pushes everything to the bottom.
Simple test code::
void MainWindow::on_pushButton_clicked()
{
ui->myScroll->setWidgetResizable(true); //making sure this is set
QPushButton *b = new QPushButton(this);
b->setText(QString("Hello Button"));
QHBoxLayout *h = new QHBoxLayout();
h->addWidget(b,0);
ui->myVBoxLayout->addLayout(h,0);
}
Result:: Left side squished (dynamic) – Right side Ok (set up manually)
Qt Creator Setup:: Left side: dynamic – Right side set up manually
Properties::
You can set use setMinimumHeight() on your buttons for preventing squished buttons. The layout can be configured with setContentsMargin() for space between item-border and item-content (QtDesigner has all four directions set to 9 IIRC) and setSpacing() for space between items (QtDesigner uses a default of 6). Also setWidgetResizable(true) allows your scrollarea to resize the view widgeth inside the area (this is where your layout and children are being placed).
This works for me:
In constructor or code set scrollArea->widget() to hold the QVBoxLayout:
v = new QVBoxLayout;
ui->scrollArea->widget()->setLayout(v);
In Button Slot:
void MainWindow::pushButtonPressed()
{
ui->scrollArea->setWidgetResizable(true);
QPushButton *b = new QPushButton(this);
b->setText(QString("Hello Button"));
QHBoxLayout *h = new QHBoxLayout();
h->addWidget(b,0);
v->addLayout(h);
}
My purpose is to create a scrollable control with a QVBoxLayout inside of it that has various controls (say buttons) on it. That control is put on a *.ui form. In the constructor for that control I write the following code:
MyScrollArea::MyScrollArea(QWidget *parent) :
QScrollArea(parent)
{
// create the scrollable container
this->container = new QWidget(); // container widget member
this->container->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
this->container->setContentsMargins(QMargins(0,0,0,0));
this->content = new QVBoxLayout(); // layout member
this->content->setMargin(0);
this->content->setSpacing(0);
for (int i=0; i<100; i++)
{
QPushButton * widget = new QPushButton();
widget->setText("button");
widget->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed);
this->content->addWidget(widget);
}
this->container->setLayout(this->content);
this->content->layout();
this->setWidget(this->container);
}
My problem: the buttons have a fixed size and do not expand horizontally. they have a fixed size. i'd like them to expand horizontally to fill the row they're in. How can I get them expanding horizontally across their parent container?
Try calling this->setWidgetResizable(true);