My main form has two panels, left docked and right docked. The right side panel has two child panels with top dock and bottom dock settings. The usercontrol is added to the right side top panel.
My usercontrol has a panel and a label. The panel is anchored on all 4 sides, the label is anchored on all except the bottom. At runtime I create this usercontrol and set it to dockstyle=fill and then I add it to my top right panel.
With everything set to "fill" I expect that when I add my usercontrol to the panel it will take on the appropriate width and height and pass that info to the child controls (labels) inside of my usercontrol.
My problem is that this stretching of the size does not happen when I create my objects during the Load event on my usercontrol. Even though initializecomponent has ran for the usercontrol the panel inside of it (4 corners anchored) has not taken the x/y values of the available space. As a result my usercontrol shows up about 50% of the width I want.
Lets say that instead of creating objects during usercontrol load that I instead start a timer and have the timer call my create routine when it raises the tick event. When I do things like this my objects are created with the full width/height that I expect. The only issue here is that this causes a delay in my interface.
Can someone help explain this behavior? My mainform is calling a "load gui" routine which is instantiating usercontrols, setting panel sizes, and then adding usercontrols to those panels. This particular user control is the last to load into the panels from that load gui routine so it does not make sense that the parent panel width/height would not be known yet. This is one of my first apps where I am purposely trying to use dockstyle=fill to keep things consistent across different main form sizes without writing all the extra size_changed code handlers. I'm sure this one is easy to work around once I know where the problem lies.
Thanks for any help provided!
this turned out to be a padding issue on the parent usercontrol. I also had to allow a bit of wiggle room to make sure that the controls didn't overflow the panel so I did a parent.width - 15 and that along with the padding made everything work much better.
Related
I have a TableLayoutPanel within a FlowLayoutPanel so that I can have a 3D border around the table, but be able to define the positions of controls within the table as I wish. I would like to have the TableLayoutPanel fill the FlowLayoutPanel but when I use the docking property, the TLP seems to bunch up at the top of the FLP.
How can I get the TLP to dock so that it will resize when the form is resized?
I generally find that Docking is more trouble than it's worth. In most cases Anchoring seems to work far better for me. Try disabling docking, then resizing the control so that it fills the panel they way you want, then setting it to anchor on left, right, top, and bottom.
Also, as others have mentioned, try using a normal panel instead of a FlowLayoutPanel. The specific layout panels have special code in them that handles resizing child elements that will probably interfere with your other resize logic.
ADDENDUM
Docking always snaps against the side of the container and forces the 2 sides on the other axis against the edges as well. Anchoring allows you to set specific positions and then tie one side of a control to it's parent so that resizing the parent keeps that side of the control the same distance from the parent. 99% of the time, in my experience, anchoring does everything that docking does and more, with far less frustration. I think that Splitterbars are the one of the few times that docking is required, but even then it can be emulated using a splitter panel. Things like ToolStrips and menus are the best use case for docking that I can think of.
I am trying to populate my windows form with new controls and data based on what is read from my database. The left side of the form is a static panel which will not need re sizing but I need to create multiple labels on the right side which requires more space. I added the vscroll control but am having trouble increasing the size of the right side of the form.
To use a scroll-bar will require a semi-low-level implementation where you need to always update the view by repositioning the elements, calculating your scroll-bar in relation to total view, what elements would be visible and so forth.
A better solution in this case will probably be to add a Panel control on the right which is docked (f.ex. Fill) and then set the AutoScroll property to True.
This way you leave all the "low level" stuff to the Panel control and you can add and position the elements you need to the Panel's Controls collection instead.
I have an application which has a tabcontrol that contains two tabpages. I have a custom made usercontrol docked to fill up each of those tabs. When I resize my main form to the minimum size allowed one tab resizes accordingly while the other seems to overflow the area and a couple ui items slip out of access/view.
One usercontrol was quite literally copied from the other and renamed and fields adjusted. The usercontrol size is the same between the two. Within the usercontrols there is a datagridview and a large panel full of textboxes and they have identical sizes and identical anchoring properties and even the same location coordinates.
I'm struggling to find a difference between the two but I really would like the resize behavior to match between the two usercontrols. I was wondering if anyone would have ideas of other things to check I did not mention here?
This should like very odd behavior.
There are a few things that I can think of to check:
1) Double-check that the user control is actually on the tab page itself and not on a different control, such as the tab or a common tab area (not sure of the tab control you are using; some controls have a common area that is available to all tabs).
2) Verify that the Dock property is indeed set to fill on the "bad" usercontrol.
3) Verify that you are not resizing or changing the Dock property on the bad usercontrol in code.
Found a minimum size on one of the usercontrols and that was the cause of my issue. Don't know how I didn't see it earlier.
Very weird situation going on with a FlowLayoutPanel...
I have been dynamically adding user controls to my panel. This user control has a height of 105. If I have my FlowLayoutPanelwidth to only show 1 "column" of controls, it will only display 296 of them. The rest of the controls are grayed out at the bottom of the flowlayoutpanel. If I widen the flp to allow 2 "columns" of controls, I can see 592 of them, with the remainder grayed out at the bottom. I have gone in and resized the user control to make it shorter in height, which works in some respects (i.e. it works when I have two columns, but not just 1), and can go forward with this work-around.
So, I guess my question is, why does the FlowLayoutPanel behave in this fashion? It seems (based on what I saw) that there is a limit to how much data the FLP will show at one time.
Your comment just reminded me that when you're adding many controls to any container it is a good idea to do this:
YourPanel.SuspendLayout();
// populate panel with controls
YourPanel.ResumeLayout(false);
This in effect stops the container (panel) from re-rendering itself every time you add a control until you're done adding controls. In the very least your panel creation will be smoother and faster. Not sure if this might fix your issue or avoid the need for a hack with PerformLayout.
If you look at your Form's designer file you will actually see this in action in the InitializeComponent function.
Sometimes, I have a picturebox lets say 100x100. But the image it will display is actually 100x400.
I don't want to increase the size of the picturebox itself. Instead, I would like to create a vertical scrollbar (or horizontal if needed).
I could not find a scrollbar in the toolbox, so I guess I have to code it. But, how?
And I still wonder if I didn't make a mistake and didn't see the scrollbar in the toolbox. My apologies then :(
I suppose you could add separate scrollbar controls and sync their Scroll events up with the offset at which the picture in the PictureBox is drawn, but that sounds like actual work. There's a better way.
Add a Panel control to your form, and set its AutoScroll property to "True". This will cause the control to automatically show scrollbars when it contains content that lies outside of its currently visible bounds. The .NET Framework will take care of everything for you under the covers, without you having to write a single line of code.
Drag and drop your PictureBox control inside of the Panel control that you just added. The Panel control will then detect that one of its child controls is larger than its visible area and show scrollbars, thanks to the AutoScroll property. When the user moves the scrollbars, the portion of the image in your PictureBox that is visible will be automatically adjusted. Magic.
(The reason you have to use a Panel control as a container is because PictureBox does not inherit directly from the ScrollableControl base class, which is what provides the AutoScroll property.)
I tried this and it worked well. But I noted that if the picturebox is docked in the panel, the picturebox is automatically set to the size of the parent panel, and can't be set larger (at least not in any way I could find). This defeats the purpose of the technique. So -- put the picturebox on the panel, but don't dock it, and it will work perfectly.
There are no automatic scroll bars on a picture box, but you can add the VScrollBar (and HScrollBar) control to the form and handle the image scrolling manually by redrawing it at a different offset each time the Scroll event is fired.