QT QIcon properties for custom widget in designer - c++

I have been working for a little while now on creating a QT custom designer widget for GUI menus. The idea being that you simply drag it into the designer, select the number of frames you'd like, how many buttons per frame, etc. and it generates and sizes everything for you.
The way the widget is structured there are properties to configure each button for the frame you are in. For example, you would use the button0Text field to enter text under Button0 while editing in frame 0, then use it again to edit Button0 which is in frame 1. Both buttons would retain the individual changes for each frame.
The Problem
Normally when I switch frames all of my properties are updated to reflect the status of the frame. The exception being QIcon. The correct icon is retained in the actual graphical representation and builds correctly, however the file path in the property list is always of the last edited for that property. I think this will be extremely confusing to an end user and I have found no way to fix it. So for example, if I set text and icons in frame 0 then switch to frame 1 the text in the property list will update to reflect the state of frame 1 but the icon path names will still show my last edit in frame 0 and not the actual icon in frame 1.
I have tried things as simple as:
setProperty("button0Icon", getButton0Icon());
That code works on properties like text, but not for the icon. I try executing it immediately after changing frames.
I have also tried:
#ifndef Q_WS_QWS
QDesignerFormWindowInterface *form = QDesignerFormWindowInterface::findFormWindow(this);
if(form){
QDesignerFormEditorInterface *editor = form->core();
QExtensionManager *manager = editor->extensionManager();
QDesignerPropertySheetExtension *sheet;
sheet = qt_extension<QDesignerPropertySheetExtension*>(manager, this);
int propertyIndex = sheet->indexOf("button0Icon");
sheet->setChanged(propertyIndex, true);
sheet->setProperty(propertyIndex, getButton0Icon());
}
#endif
And:
int propertyIndex = this->metaObject()->indexOfProperty("button0Icon");
QMetaProperty property = this->metaObject()->property(propertyIndex);
property.write(this, QIcon());
Nothing seems to update the property list in the designer.
I have all properties, including all QIcon properties properly declared in the header file with Q_PROPERTY and assigned getter and setter functions.
To be clear, the icon values are indeed retained through each frame when compiled. So it is functioning, just unclear for most users.
If anyone has any experience with this or any ideas please let me know. Thanks.

I have discovered that QIcon does not store file names/paths. The file names are only used for the creation of the QIcon. I think this is most likely the reason I do not get any feedback in the Property Browser for my QIcon properties.
Instead I have chosen to hide this property in the designer and add three new ones. Three QUrl properties, each of which is used to supply an image file. I use three because I want to construct a QIcon that contains Modes/States for normal, disabled, and pressed operations.
I take each of these QUrls and save them in QStringLists behind the scenes so their values are stored. I then construct my QIcon using the file names provided from the QUrls.
I would much prefer to be using the native QIcon in the designer for this, any thoughts or feedback are appreciated.

Related

QTextEdit change font of individual paragraph/block

Using a QTextEdit, I need to change the font attributes of each paragraph individually. This is similar to how many word processors change the font of a paragraph when the user select a style from a menu (not a specific formatting).
Ideally, I would like to apply a QTextCharFormat (or equivalent) to a block (paragraph) just before it is laid out and rendered, but I would prefer that no font attribute be actually inserted in the text, as I don't want this information in the file but I need to preserve any bold/italic/underline attributes that the user might have set to words within paragraphs (I intend to save the needed information in a QTextBlock::userData). However, I can't figure where I would need to insert a function to perform this task.
I figured I could not change the QTextCharFormat of a paragraph from either QTextBlock nor QTextCursor as this only applies to new blocks, it doesn't affect blocks with existing text.
I checked out QTextLayout but I don't think my answer is there.
I have been looking for a solution to this problem for a few days now. I would be really gracious for any pointer in the right direction.
I have years of experience with C++, but I'm somewhat new to Qt. Using Qt 4.8.
Edit:
I added emphasize (bold) above to an important part of what I'm trying to do. In other word, what I'd really like to do is be able to apply the font attributes to the block of text (perhaps a temporary copy) just before it is displayed. I'm totally comfortable with deriving and modifying (even reimplement) any class that I need to in order to achieve that goal, but I need to be pointed to the right direction as to what I actually need to change. As a last resort, I could also modify some Qt class directly if that is necessary for the task, but again would need to know what class I need to touch. I hope this is clearer. I find it difficult to explain this without being allowed to tell you what the application will do exactly.
[Required Libraries]
#include <QTextEdit> // not needed if using the designer
#include <QTextDocument>
#include <QTextBlock>
#include <QTextCursor>
[Strategy]
QTextDocument
I need it to manage the blocks. The function QTextDocument::findBlockByNumber is quite handy to locate the previous blocks, and I think it is what you are after.
QTextBlock
Container for block texts. A nice and handy class.
QTextCursor
Surprisingly, there is no format-setter in QTextBlock class. Therefore I use QTextCursor as a workaround since there are four format-setters in this class.
[Code for formatting]
// For block management
QTextDocument *doc = new QTextDocument(this);
ui->textEdit->setDocument(doc); // from QTextEdit created by the Designer
//-------------------------------------------------
// Locate the 1st block
QTextBlock block = doc->findBlockByNumber(0);
// Initiate a copy of cursor on the block
// Notice: it won't change any cursor behavior of the text editor, since it
// just another copy of cursor, and it's "invisible" from the editor.
QTextCursor cursor(block);
// Set background color
QTextBlockFormat blockFormat = cursor.blockFormat();
blockFormat.setBackground(QColor(Qt::yellow));
cursor.setBlockFormat(blockFormat);
// Set font
for (QTextBlock::iterator it = cursor.block().begin(); !(it.atEnd()); ++it)
{
QTextCharFormat charFormat = it.fragment().charFormat();
charFormat.setFont(QFont("Times", 15, QFont::Bold));
QTextCursor tempCursor = cursor;
tempCursor.setPosition(it.fragment().position());
tempCursor.setPosition(it.fragment().position() + it.fragment().length(), QTextCursor::KeepAnchor);
tempCursor.setCharFormat(charFormat);
}
Reference:
How to change current line format in QTextEdit without selection?
[DEMO]
Building Environment: Qt 4.8 + MSVC2010 compiler + Windows 7 32 bit
The demo is just for showing the concept of setting the format on a specific block.
Plain text input
Format 1 (notice that it won't bother the current cursor in view)
Format 2
You can use QTextCursor to modify existing blocks.
Just get a cursor and move it to the beginning of the block. Then move it with anchor to create a selection.
Set this cursor to be the current cursor for the text edit and apply your changes.
QTextEdit accepts HTML so all you have to do is to format your paragraphs as HTML. See example below:
QString text = "<p><b>Paragraph 1</b></p><p><i>Paragraph 2</i></p>";
QTextCursor cursor = ui->textEdit->textCursor();
cursor.insertHtml(text);
That will create something like this:
Paragraph 1
Paragraph 2
Having said that, there is only a subset of HTML that is supported in Qt. See Supported HTML Subset

Use a pointer to switch between two other pointers in Qt Creator Ui

i do have two Labels in my applications. They are both in each tab. Now i want to witch between those labels by using an pointer that switchs between those labels when tab was changed.
my ui_mainwindow.h defines:
ProLabel *imageLabel;
ProLabel *imageLabel_1;
ProLabel *imageLabel_2;
but only imageLabel_1 and imageLabel_2 are shown in the GUI. I added a third Label (imageLabel) to use it as a variable to switch between the Labels (1/2). So I wrote follwing code in a slot which proves tab changed. So if tab is changed, the other imageLabel_1/2 (pointer) should be used in the hole code, when it says: imageLabel.
my slot when tab changed:
if(tab == 0)
{
this->ui->imageLabel = this->ui->imageLabel_1;
}
else{
this->ui->imageLabel = this->ui->imageLabel_2;
}
I also set the imageLabel_1 whe MainWindow is created. The Window disapear like normal. But if I try to load an image (than it should display the image in the imageLabel) it crashes.
Don't know if it was understandable. Does anybody has an idea if i can handle the pointers like that.. or how to do it different?
Thank you!
Two simpler ways: 1) Change the label contents, either the image or the text it contains, or 2) set the label to hidden with ui->label2->isVisible(false).

Taking data from a Dialog in Qt and using it in a Ui

So I'm making a text editor using Qt and right now I have a button that opens a dialog called "Format text". I want it to work kind of like the dialog in notepad called "font" where you select a few text attributes from some drop down lists and it shows you what your text will look like. Right now I have it working where you can select the font style, font color, and font size and hit preview and it shows you in a box in the dialog what your text will look like. However, I have a button called "okay" which is supposed to change the highlighted text or the text you are about to type, but I can't figure out how to display those changes on the main window. The .ui files are private and a lot of the already made functions and pointers are the same in every ui file so if I change the ui file to pubic I have to change a whole bunch of things. Can anyway give me a simple answer? I'm trying to do this with as little confusion as possible. More coding and less confusion is better than less coding and more confusion for someone of my skill level. Sorry that this is all one giant paragraph and that I didn't provide any code, but I didn't think the code was necessary, however if you do need some of the code i'd be happy to share it.
Thank you for your help and your time. I hope you all have a nice evening.
QDialog have a signal called finished(), you can connect this signal with your slot. To accomplish your work, pass a QSettings or for simplicity QStringList to dialog settings (responsible for changing font, color ...), the QStringList will save user defined settings, after closing the dialog, iterate through QStringList member to alert Main window.
A pseudo code will look like this
Class Editor:
Editor::Editor()
{
TextSettings textSettings;
textSettings.setSettings(settings); // settings is a member
connect(textSettings, &finished(int)), this, SLOT(alertEditor(int)))
}
Editor::alertEditor(int s)
{
if(s == 0)
{
for (int i = 0; i < settings.size(); ++i)
settings.at(i).toLocal8Bit().constData(); // extract various user settings
}
}
Class TextSettings:
TextSettings::TextSettings(QStringList settings)
{
settings << ui->combobox->currentItem(); // font name as example
}

Using images in QListWidget, is this possible?

I am using QT to create a chat messenger client. To display the list of online users, I'm using a QListWidget, as created like this:
listWidget = new QListWidget(horizontalLayoutWidget);
listWidget->setObjectName("userList");
QSizePolicy sizePolicy1(QSizePolicy::Preferred, QSizePolicy::Expanding);
sizePolicy1.setHorizontalStretch(0);
sizePolicy1.setVerticalStretch(0);
sizePolicy1.setHeightForWidth(listWidget->sizePolicy().hasHeightForWidth());
listWidget->setSizePolicy(sizePolicy1);
listWidget->setMinimumSize(QSize(30, 0));
listWidget->setMaximumSize(QSize(150, 16777215));
listWidget->setBaseSize(QSize(100, 0));
listWidget->setContextMenuPolicy(Qt::CustomContextMenu);
Users are shown by constantly refreshing the list, like this: (Note: There are different channels, with different userlists, so refreshing it is the most efficient thing to do, as far as I know.)
void FMessenger::refreshUserlist()
{
if (currentPanel == 0)
return;
listWidget = this->findChild<QListWidget *>(QString("userList"));
listWidget->clear();
QList<FCharacter*> charList = currentPanel->charList();
QListWidgetItem* charitem = 0;
FCharacter* character;
foreach(character, charList)
{
charitem = new QListWidgetItem(character->name());
// charitem->setIcon(QIcon(":/Images/status.png"));
listWidget->addItem(charitem);
}
}
This has always worked perfectly. The line that I commented out is the one I have problems with: my current goal is to be able to display a user's online status with an image, which represents whether they are busy, away, available, etc. Using setIcon() does absolutely nothing though, apparently; the items still show up as they used to, without icons.
I'm aware that this is probably not the way this function needs to be used, but I have found little documentation about it online, and absolutely no useful examples of implementations. My question is, can anybody help me with fixing this problem?
This is how you may conduct your debugging:
Try the constructor that has both icon and text as arguments.
Try to use that icon in another context to ensure it is displayable (construct a QIcon with same argument and use it elsewhere, e.g. QLabel!).
Use icon() from the QListWidgetItem to receive back the icon and then look at that QIcon.
Create a new QListWidget, change nothing, and ordinarily add some stock items in your MainWidget's constructor. See if the icons show up there.

MFC: Displaying a tabulated display of text items

This should be simple it seems but I can't quite get it to work. I want a control (I guess CListBox or CListCtrl) which displays text strings in a nice tabulated way.
As items are added, they should be added along a row until that row is full, and then start a new row. Like typing in your wordprocessor - when the line is full, items start being added to the next line, and the control can scroll vertically.
What I get when trying with a list-mode CListCtrl is a single row which just keeps growing, with a horizontal scroll bar. I can't see a way to change that, there must be one?
You probably need a list control wth LVS_REPORT. If you expect the user to add items interactively using a keyboard, you probably need a data grid, not a list. Adding editing to list control subitems is not easy, and it would be easier to start from CWnd. Search "MFC Data Grid" to find some open source class libraries that implemented the feature.
If you can afford adding /clr to your program, you can try the data grid classes in Windows Forms using MFC's Windows Form hosting support. You will find a lot more programming resources on data grid classes in Windows Forms than any other third-party MFC data grid class library.
If you use CRichEditCtrl you can set it to word-wrap, take a look at this snippet extracted from:
http://www.tech-archive.net/Archive/Development/microsoft.public.win32.programmer.ui/2004-03/0111.html
(I've derived my own QRichEditCtrl from the MFC CRichEditCtrl,
and here's the relevant code:)
void QRichEditCtrl::SetWordWrap(bool bWrap)
{
RECT r;
GetWindowRect(&r);
CDC * pDC = GetDC();
long lLineWidth = 9999999; // This is the non-wrap width
if (bWrap)
{
lLineWidth = ::MulDiv(pDC->GetDeviceCaps(PHYSICALWIDTH),
1440, pDC->GetDeviceCaps(LOGPIXELSX));
}
SetTargetDevice(*GetDC(), lLineWidth);
}