Julia gui display an image gtk.jl - julia

How can I display an image using Gtk with Julia?
In my GUI, I have a button set up so when I click the button, my program will show the image in the GUI? I haven't found any documentation about it on the official Gtk.jl Docs.

this should do the trick!
using Gtk
win = GtkWindow("My First Gtk.jl Program", 400, 200)
a = GtkImage("path_to_image_file")
push!(win,a)
showall(win)
Note that I am not sure if it can render in the same window as the button you mentioned since I get the following error when I have a button and then push the image:
(<unknown>:69811): Gtk-WARNING **: 15:34:18.724: Attempting to add a widget with type GtkImage to a GtkWindow, but as a GtkBin subclass a GtkWindow can only contain one widget at a time; it already contains a widget of type GtkButton

This uses ImageView to do the image display, which gives you control of aspect ratio, zoom, pan, contrast-settings, and movie-player widgets "for free":
using Gtk, ImageView, TestImages
b = GtkButton("Click Me")
frame, c = ImageView.frame_canvas(:auto)
bx = GtkBox(:v)
push!(bx, frame)
push!(bx, b)
win = GtkWindow("My First Gtk.jl Program", 400, 200)
push!(win, bx)
Gtk.showall(win)
img = testimage("lighthouse")
imshow(c, img)
with result
The dictionary that imshow returns allows you to interact programmatically with what's on the screen.
If you want to learn more, see the documentation at ImageView and GtkReactive.
That said, the suggestion to try Makie may be a very good one.

Related

Animating a frame to pop out of the bottom of the app without shrinking the height of other elements

I'm working on a desktop application for windows using PyQt and Qt creator.
What I want
I want to display messages to the user only when the user gave an input. I also wanted the message to draw the eye, so I'm going for the following animated solution:
A frame that's hidden when not required (with height = 0 and width = the app's width), 'grows' from the bottom of the app when needed, stays visible for 5-6 seconds, then retracts back to the bottom.
The app kind of looks like this without the message:
And kind of like this when the message IS displayed (note how the bottom gray element is 'covered' by the message):
What I tried
So the way I did this was to create what I called "footer frame", which contains another frame that I call "message frame". The message frame contains a label that will hold, in time, the message for the user. Everything has pre-determined height, so to hide the whole thing I set the message frame to have a maximum height of 0.
So for the 'growing' animation I animated the message frame's maximumHeight property.
The current problem
THING IS - since I wanted the app to be responsive I put everything in layouts... and because of that, whenever the message is displayed, the rest of the components are 'compressed' in height.
kind of like this (note how the bottom gray element is not covered by the message, but all the elements' heights shrink a little):
Instead, I wanted the messsage to 'cover' whatever is located under the message's coordinates.
I tried to animate the geometry of the message frame, but nothing really happened - probably because the minimum height is still 0. So I tried to change the minimum height right before the animation begins; But that led to that compression again.
Tried to do the same with the footer frame, with the same results.
My question is : What is the best / preferred way of achieving the result I intend with Qt?
Layout managers always try to show all widgets they're managing. If you want a widget to overlap others, you cannot put it inside a layout, you just create the widget with a parent, and that parent will probably be the widget containing the layout above or the top level window.
This cannot be done in Designer/Creator, as it's assumed that once a layout has been set for a parent widget, all child widgets will be managed by that layout. The only solution is to do this programmatically.
In the following example I'm assuming a QMainWindow is used, so the reference parent widget is actually the central widget, not the QMainWindow: that's because the alert should not cover other widgets that are part of a main window's layout, like the status bar or a bottom placed tool bar or dock).
The animation is actually a QSequentialAnimationGroup that shows the rectangle, waits a few seconds, and hides it again. Since the window could be resized while the animation is running, a helper function is used to properly update the start and end values of the warning and eventually update the geometry when in the "paused" state (which is actually a QPauseAnimation); in order to do so, an event filter is installed on the central widget.
from random import randrange
from PyQt5 import QtCore, QtWidgets, uic
class MyWindow(QtWidgets.QMainWindow):
def __init__(self):
super().__init__()
uic.loadUi('overlay.ui', self)
self.alerts = []
self.centralWidget().installEventFilter(self)
self.pushButton.clicked.connect(self.showAlert)
QtCore.QTimer.singleShot(2000, self.showAlert)
def showAlert(self, message=None, timeout=250):
# create an alert that is a child of the central widget
alert = QtWidgets.QLabel(message or 'Some message to the user',
self.centralWidget(), wordWrap=True,
alignment=QtCore.Qt.AlignCenter,
styleSheet='background: rgb({}, {}, {});'.format(
randrange(192, 255), randrange(192, 255), randrange(192, 255)))
self.alerts.append(alert)
alert.animation = QtCore.QSequentialAnimationGroup(alert)
alert.animation.addAnimation(QtCore.QPropertyAnimation(
alert, b'geometry', duration=timeout))
alert.animation.addAnimation(QtCore.QPauseAnimation(3000))
alert.animation.addAnimation(QtCore.QPropertyAnimation(
alert, b'geometry', duration=timeout))
# delete the alert when the animation finishes
def deleteLater():
self.alerts.remove(alert)
alert.deleteLater()
alert.animation.finished.connect(deleteLater)
# update all animations, including the new one; this is not very
# performant, as it also updates all existing alerts; it is
# just done for simplicity;
self.updateAnimations()
# set the start geometry of the alert, show it, and start
# the new animation
alert.setGeometry(alert.animation.animationAt(0).startValue())
alert.show()
alert.animation.start()
def updateAnimations(self):
width = self.centralWidget().width() - 20
y = self.centralWidget().height()
margin = self.fontMetrics().height() * 2
for alert in self.alerts:
height = alert.heightForWidth(width) + margin
startRect = QtCore.QRect(10, y, width, height)
endRect = startRect.translated(0, -height)
alert.animation.animationAt(0).setStartValue(startRect)
alert.animation.animationAt(0).setEndValue(endRect)
alert.animation.animationAt(2).setStartValue(endRect)
alert.animation.animationAt(2).setEndValue(startRect)
def eventFilter(self, obj, event):
if obj == self.centralWidget() and event.type() == event.Resize and self.alerts:
self.updateAnimations()
for alert in self.alerts:
ani = alert.animation
# if the animation is "paused", update the geometry
if isinstance(ani.currentAnimation(), QtCore.QPauseAnimation):
alert.setGeometry(ani.animationAt(0).endValue())
return super().eventFilter(obj, event)
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
w = MyWindow()
w.show()
sys.exit(app.exec())

Get Geometry of widgets with variable size

Situation
I have a pop_up widget (say a textbox), which I can place arbitrarily on the screen by setting the properties x and y accordingly.
On the other hand I use the prompt, which is located in the default wibar.
I would like to place the pop_up widget directly below the prompt
Problem
I was not yet able to gather any useful information about the geometry of the prompt. With geometry I mean its x and y values together with its height and width. I solved the y-positioning by using the height of the wibar itself.
But I am stuck with x-positioning.
Is there a way to get the width of the widgets within the toolbar?
Notice
I read something about forced_width, but in this situation it sounds like a hack to me. So I would prefer to avoid forcing any widths.
I'm currently running awesome WM 4.2 on Fedora 26
Part of a problem is that "a" widget does not have a position and size since awesome allows widgets to be shown in multiple places at once. However, if we just ignore this problem, something like the following could work (to be honest: I did not test this):
function find_widget_in_wibox(wb, widget)
local function find_widget_in_hierarchy(h, widget)
if h:get_widget() == widget then
return h
end
local result
for _, ch in ipairs(h:get_children()) do
result = result or find_widget_in_hierarchy(ch, widget)
end
return result
end
local h = wb._drawable._widget_hierarchy
return h and find_widget_in_hierarchy(h, widget)
end
However, I have to warn you that the above could break in newer versions of awesome since it access non-public API (the part with wb._drawable._widget_hierarchy). There is a way to work with just the public API using :find_widgets(), but I am too lazy for that for now.
The above function gets the wibox.hierarchy instance representing a widget which allows to get the geometry of the prompt via something like the following (in the default config of awesome 4.2):
local s = screen.primary -- Pick a screen to work with
local h = find_widget_in_wibox(s.mywibox, s.mypromptbox)
local x, y, width, height = h:get_matrix_to_device()
:transform_rectangle(0, 0, h:get_size())
local geo = s.mywibox:geometry()
x, y = x + geo.x, y + geo.y
print(string.format("The widget is inside of the rectangle (%d, %d, %d, %d) on the screen", x, y, width, height)
Finally, note that the widget hierarchy is only updated during repaints. So, during startup the code above will fail to find the widget at all and right after something changed (e.g. you entered another character into the promptbox), the above will still "figure out" the old geometry.

Windows Small System Icon Height Incorrect

I'm running on Windows 10, but using Delphi 7 (yes, I know it's quite old).
I want to use the system icons in Windows and have gone about this by defining a TImageList called SystemIcons which I initialize as follows:
var
fileInfo: TSHFileInfo;
begin
SystemIcons.Handle := ShGetFileInfo('', 0, fileInfo, SizeOf(fileInfo),
SHGFI_ICON or SHGFI_SMALLICON or SHGFI_SYSICONINDEX);
...
I have SystemIcons properties set statically as a TImageList component with width and height set to 16.
Elsewhere, I wish to retrieve an icon from this image list given a valid shell object's image index. Because these are "small system icons", I expect them to be 16x16. The result of calling GetSystemMetrics(SM_CYSMICON) yields 16. Oddly, the dimensions depend upon whether I retrieve them as a bitmap or an icon.
...
var
icon: TIcon;
bm: TBitmap;
begin
...
icon := TIcon.Create;
SystemIcons.GetIcon(imgIndex, icon);
bm := TBitmap.Create;
SystemIcons.GetBitmap(imgIndex, bm);
The imgIndex is correct and the same in both cases. The image retrieved is the same in each case, as expected. The dimensions of the bitmap (bm.Width and bm.Height) are also as expected: 16x16. However, the dimensions of the icon (icon.Width and icon.Height) are not. They are 32x32.
When I paint the icon on a canvas it appears as 16x16. So it's only its Height and Width values that appear incorrect. Very odd.
Why are these different?
The images are likely actually 32x32 to begin with.
Internally, TImageList.GetIcon() simply retrieves an HICON for the chosen image directly from the underlying Win32 ImageList API, using ImageList_GetIcon(), and assigns that to the TIcon.Handle property.
TImageList.GetBitmap(), on the other hand, is a bit different. It sizes the TBitmap to the dimensions of the TImageList (16x16), and then stretch draws the chosen image onto the TBitmap.Canvas using TImageList.Draw(), which in turn uses ImageList_DrawEx().

Squish test for clicking exit/minimize/maximize button for QT application

I have an application that is suppose to run in full screen and not allow the user to minimize or exit with the use of the minimize and exit buttons that usually appear on the corner of the window. Essentially the title bar or whatever it is called is not visible.
I'm trying to make a test where squish checks whether the exit/minimize buttons can be pressed or is visible. Is there a way to do this?
When I try to use Spy or record function all I get is the window commands for minimize/exit a window but no clickbutton or a way to verify the visibility of the buttons.
Thanks!
I asked squish tech support and they recommended using the qt window flags such as:
def logWindowFlags(flags):
test.log("Qt::WindowMinimizeButtonHint = %s" % flags.testFlag(Qt.WindowMinimizeButtonHint))
test.log("Qt::WindowMaximizeButtonHint = %s" % flags.testFlag(Qt.WindowMaximizeButtonHint))
test.log("Qt::WindowCloseButtonHint = %s" % flags.testFlag(Qt.WindowCloseButtonHint))
test.log("Qt::WindowOkButtonHint = %s" % flags.testFlag(Qt.WindowOkButtonHint))
def main:
logWindowFlags(widgetObject.windowFlags())

Using PyQt and Qt4, is this the proper way to get a throbber in a QTabWidget tab?

I have some code creating a QTabWidget from Python using PyQt4. I want to get a 'throbber' animated gif in the tab. The /only way/ I have found how to do this is the following convoluted method.
tabBar = self.tabReports.tabBar()
lbl = QtGui.QLabel(self.tabReports)
movie = QtGui.QMovie(os.path.join(self.basedir, "images\\throbber.gif"))
lbl.setMovie(movie)
QtCore.QObject.connect(movie, QtCore.SIGNAL("frameChanged(int)"), lambda i: movie.jumpToFrame(i))
movie.start()
log.debug("valid = %s"%(movie.isValid()))
tabBar.setTabButton(idxtab, QtGui.QTabBar.LeftSide, lbl)
The debugging call always returns true, but the throbber sometimes works, sometimes is blank, and sometimes has a large ugly delay between frames. In particular, I can't help but think connecting the frameChanged signal from the movie to a function that simply calls jumpToFrame on the same movie is not correct.
Even more distressing, if I simply drop the lambda (That is, make the line say QtCore.QObject.connect(movie, QtCore.SIGNAL("frameChanged(int)"), movie.jumpToFrame) it never renders even the first frame.
So, what am I doing wrong?
PS: I realize .tabBar() is a protected member, but I assumed (apparently correctly) that PyQt unprotects protected members :). I'm new to Qt, and i'd rather not subclass QTabWidget if I can help it.
I believe the problem with the code I initially posted was that the QMovie didn't have a parent, and thus scoping issues allowed the underlying C++ issue to be destroyed. It is also possible I had had threading issues - threading.thread and QThread do not play nice together. The working code I have now is below - no messing with signals nor slots needed.
def animateTab(self, tab_widget, enable):
tw = tab_widget
tabBar = tw.tabBar()
if enable:
lbl = QtGui.QLabel(tw)
movie = QtGui.QMovie("images\\throbber.gif"), parent=lbl)
movie.setScaledSize(QtCore.QSize(16, 16))
lbl.setMovie(movie)
movie.start()
else:
lbl = QtGui.QLabel(tw)
lbl.setMinimumSize(QtCore.QSize(16, 16))
tabBar.setTabButton(tab_section.index, QtGui.QTabBar.LeftSide, lbl)
I faced the same problem and this posting helped to make it work:
http://www.daniweb.com/forums/printthread.php?t=191210&pp=40
For me this seems to make the difference: QMovie("image.gif", QByteArray(), self)

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