Resizing frames in Tkinter - python

I have been making a small program with the Tkinter module in python, and I was wondering whether it was possible or not to resize a frame in my program with the mouse. As in, the user can drag the frame border and it will resize itself.

Your use of terminology makes the question unclear. Windows which may be resized by the user are called Toplevel windows. These are what appear as rectangular windows on the display, with a frame around them, typically a title bar, and edges or corners that can be grabbed and resized.
The term Frame refers to a container widget that must be inside a Toplevel or one of its descendents. A Frame has the ability to be resized but you have to write the code to let you interactively resize them. For example, you could place a little grip widget in one or more corners, and writing bindings to the press, motion and release of a mouse button.
Depending on the effect you are looking for, you might want a PanedWindow which is a container that includes a sash that lets you adjust the proportion of space between two other widgets.

Related

Overlay all screens and draw rectangle with a mouse

I am working on tiny program to capture screen print, I want to do it in a similar fashion that Win Snipping Tool is working. First I need to overlay all screens with a 50% opacity layer and then, using the mouse, draw a rectangle and read vertices coordinates. Honestly, I have no idea how to bite this. I tried with win32api / gui and it is great to get mouse coordinates, but still was unable to draw a rectangle. My idea (one of many) is to (using PIL / ImageGrab) take shots of both displays, put an overlay and print them as a full screen on all windows, but I failed while doing this. Other idea is to take img grab and create two new windows using BeeWare / Toga (that is GUI framework I am using) in full screen, but I was unable to find any method to open window on second display. Any ideas and hints will be greatly appreciated, I am really counting on you, as I feel I reached dead end.
Well,It is very easy to use tkinter.
Ok,It is the principle when I make my screenshot application:
User presses the button to start.
Make a new window whose width and height should full cover all the screens,and hide the title bar(If it is had to achieve,maybe use width=9999 and height=9999).
Take a screenshot of all the desktop(You can use ImageGrab.grab((),all_screens=True)) to do that.
Make the screenshot showed in a Canvas(I know that toga have this widget).
Start your mouse listener thread and save the position of pressed.
When user moves his mouse,create a rectangle(toga's Canvas have a function rect()).Maybe use this rect(pressed_x,pressed_y,move_x,move_y).And delete the last rectangle(Then it will always show only one rectangle).
When user released his mouse,save the position of released.And use ImageGrab.grab((pressed_x,pressed_y,released_x,released_y),all_screens=True) to crop the selected area.
If you want to show it in application interface.toga has a widget called ImageView.You can put the image in it.

How to resize images in a canvas dynamically in tkinter?

In Tkinter, resizing a canvas and/or frame can be done using
canvas.pack(fill="both", expand=True)
This way I can drag the tkinter window with the mouse and the canvas and frames within will adapt to the new size.
However I have not found a solution for applying this to images within the canvas. Only solutions so far are to independently change the size of the images through event actions.
Is there any way to make images within a canvas to resize dynamically, just like the canvas does with the one-liner above?
Is there any way to make images within a canvas to resize dynamically, just like the canvas does with the one-liner above?
No, there is no way to do what you want. Images aren't like widgets which can automatically grow and shrink. You will need to set up a binding on the <Configure> event of the containing widget, and in the bound function you will have to convert the image to the desired size.

Tkinter: Resizing scrollbar without adjusting window size

I currently have a scrollbar and a canvas on the same hierarchical level. In the canvas, there is a frame created using the canvas' create_window method.
I have a binding that is called when the canvas is configured that will resize the scrollregion to fit bbox("all"). It works, but ONLY when the entire window is resized (e.g. If I add more widgets to the canvas that are now not in its visible region, I have to resize the window to be able to change the canvas' scrollregion).
Ideally, the scrollregion should change as soon as the new widget is added to a nonvisible location of the canvas (e.g. it's off the screen). What am I currently doing incorrectly? Any advice is appreciated!
If I am reading your mind correctly (you really need to include a Minimal, Complete, Verifiable Example with debugging questions!), you are recalculating the scrollregion only on receipt of a <Configure> event. That only triggers when the widget changes size - and calling .create_window() on a Canvas certainly doesn't change its size. The simplest solution would probably be to explicitly do the scrollregion recalc yourself, every time you add widgets to it (there's no event that is triggered by this action, as far as I know). You might need to call .update_idletasks() first, to give the newly-added widget a chance to calculate its own size.
You need to put a binding on the inner frame's <Configure> event to also reset the scrollregion.

Achieving a facebook-like modal dialog in GTK+ (linux)

Ideally, the transparent border.
Here's an example of what i'd like to achieve:
Notice the transparent border.
Now i suppose I could use cairo to create a rectangle with transparency, and put a borderless non-transparent window inside, mimic'ing that effect - which I would if i knew the window would have a fixed dimension. However, if the inner window grows, it'll grow out of the transparent rectangle.
How should one approach such task?
Making window frames is really the job of the window manager (at least under X11, don't know how it works on windows).
But have a look at the GtkBin, GtkBox or GtkMisc widgets. Pack the dialog inside it as a single widget, and use padding to give it a size. Read up on GTK+ drawing model. You will probably need to set a flag and define your own expose-event handler to re-draw your frame.

Widget Transparency in PyGTK?

What is the best way to have transparency of specific widgets in a PyGTK application? I do not want to use themes because the transparency of each of the widgets will be changing through animation.
The only thing I can find is to use cairo to draw widgets with an Alpha, but I can't figure out how to do this. Is there perhaps a better way to do this as well?
Thanks!
Assuming that your program runs under composition manager, you could get per-widget transparency by manipulating widget's X window. Look at gtk.gdk.Window.set_opacity().
Note, it is not gtk.Window; you can get this object by getting its window property (buttonWidget.window), but only when widget is realized and only when widget does handle events -- gtk.Label does not have its own X window for instance.
If you need to work also when you don't have composition manager, drawing your widgets by yourself is the only option -- but you don't necessarily have to use cairo; drawing pixel by pixel on the bare X window will also work.

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