I was wondering if there is a way to setup a level indicator inside the track of the .NET TrackBar?
My usage scenario is this. I need an audio squelch control. So I want to use a TrackBar where the user drags between 0 and 100 squelch. But at the same time I want to show the current audio level in the track of the TrackBar. So that the user knows where the current audio level is relation to the squelch.
Any suggestions? Is this something were I need to override the paint method of the TrackBar? Or is there a free control somewhere I could use?
This will not be as easy as it might seem. One cannot simply augment the appearance of the TrackBar control. You have to trigger UserPaint by adding the following line to the constructor of a class that derives from TrackBar:
SetStyle(ControlStyles.UserPaint, true);
This will, however, force you to own all of the painting. Meaning that you will then need to override both OnPaint and OnPaintBackground and use the methods in TrackBarRenderer to paint the entire control.
Having said that, the methods given to you are pretty straightforward, and drawing the control is relatively easy.
Note: this Code Project article is bound to have lots of good pointers if you decide to pursue full-on custom drawing. Perhaps could even serve as your replacement control.
There are others. Just do a Google search for "C# TrackBar custom draw".
Related
I have created a custom control of my own and i am in a need of making this custom control as a ToolTip for the Labels or Buttons.
But i could not find a way to set the Custom control as ToolTip.
Anyone please help me on setting the Custom control as ToolTip.
Note:
I don't need solution with showing the Custom Control in mouse_hover events of controls.
Please suggest me ideas to make the custom control as default ToolTip in standard way.
Regards,
Amal Raj
I assume that you already know about overriding the paint event, so I won't go into that. If you want anything a bit more complicated, deriving from the ToolTip control to extend it for your purposes won't make much sense since you'll run into restrictions quite fast.
What you should do is implement your own ToolTip control by reusing some important bits from the original one. If you're feeling adventurous you could follow these steps to get started. I'm going to refer to your custom control as tooltip from now on:
If you want to show custom text or something else for each control that uses your tooltip, you need to implement IExtenderProvider in your class. Here's more about it.
You need to keep track of controls that are using your tooltip and the custom values you've set for them. Internally, Windows Forms tooltip uses a HashTable for that purpose. Key is the control showing your tooltip and value is the tooltip text (or something else you want to tie to your tooltip).
If you want to have more than just one string to show (title, description, image etc), you can have multiple HashTables.
When adding the tooltip to a control, subscribe to mouse events (enter, move, leave) to keep track of when to show the tooltip. If you want to have a delay before showing the control, you need to use an internal timer to keep track of time.
You'll most likely want the tooltip to extend outside the main form's boundaries. You could wrap your tooltip inside a headerless form or an alpha blended form to allow other shapes than rectangle.
Those are the very generalized first steps. In reality, there's quite a bit more to be done. It's been a few years since I implemented my custom ToolTip control so I might be forgetting something crucial. However, if you spend some time poking around the code of Windows Forms's ToolTip class, you'll get quite a good idea of what's going on behind the curtains.
I haven't reviewed the code myself but judging from the ratings, this article will give you a good starting point too: A ToolTip with Title, Multiline Contents, and Image. It's in VB.NET but you can easily convert it to C# by using Telerik's converter or any other.
At this point, I almost never want to design a control with rich design-time support again. That said...
I am already overriding the SnapLines property in my ControlDesigner-derived class to manually forward out various snaplines from the child controls of my control -- the text baseline (pink) snap from the labels and comboboxes; the text inset snap from the labels; the top, bottom, left and right snaplines from the comboboxes. Those snaplines activate when the control itself is moved around on the form and when other controls are moved around it.
What I need is the ability to tell the designer to activate the snaplines and then deactivate them while I'm doing an internal move or resize of the underlying controls.
My comboboxes are resizable through overrides of OnMouseDragBegin, OnMouseDragMove, and OnMouseDragEnd in my control designer. The magic bullet I'm looking for is something I can call in Begin to tell the designer to show the snaplines and something in End to tell it to stop.
Allowing people to resize and move the internal controls at design time is kind of useless if they don't show snaplines for each other or for external controls.
As with stuff like this, it's incredibly hard to search for. I've found one post on a forum where someone asked this exact question that had (of course) no responses. That's about it.
Obviously the issue of actually snapping to the snaplines when/if they're shown remains. Just being able to see them would be a nice start.
Any ideas?
The best way to do what you want todo is to create a Design Surface MSDN Reference
I've used this to create my own design surface for my application so that the clients can customize the forms.
Hope this helps,
Johan J v Rensburg
I have a User Control that has some WinForm Controls inside. I want to be able to paint those inner controls myself (for scrolling purposes, some of them will remain, others will move).
Even when I override the OnPaint and the OnPaintBackground method, those controls keeps showing on my usercontrol which is completely black now because there is no painting methods on it.
Is there a way I can suppress those controls from been painted and then paint them by myself with the DrawToBitmap method of each control?
Yes. Remove them from (or better yet, never add them to) the UserControl's set of child controls. Simulating interaction with the controls is going to be a PITA, though.
Do you just need the controls to "look" like they're there. Or do they need to actually be there? If its the latter, you would be better off faking the scrolling somehow by just repositioning the controls manually.
Trying to re-invent the windowing system is an exercise in pain. You will be better off if you learn and work within its paradigms.
If you don't need interaction, just set every child control .Visible = false.
Otherwise, have you tried WM_SETREDRAW?
I would like to learn about creating a program that I could draw simple shapes and be able to select them for editing - like resizing, order of display, color change. Is there an online resource that someone knows of that would help me reach my goals.
thanks
"GDI+" is what you are looking for. You can start here: http://msdn.microsoft.com/en-us/library/da0f23z7.aspx
A sneaky way I used to do it was to create a custom control, remove the background from it and paint my shapes and sizes on it. Then, you can easily implement selection (override OnClick), dragging and resizing (OnMouseDown, OnMouseMove, OnMouseUp). You can then implement options like color, etc. by means of a property (see Browsable attribute and property get/setters) and a PropertyGrid control.
Anything beyond that, though - Bezier curves and such - would need something a tad more advanced, though.
The alternative is to only use such controls for the sizing handles, and do all the drawing on one central canvas - the only drawback then is figuring out how to select a shape on the canvas.
What would be the best WPF control in C# (VS 2008) that you can place on a form that would allow you to do drawing similar to the "Paint" function for the CWnd class in C++? Also, that could display bitmaps, have a scroll bar, and the ability to accept user inputs (ie. MouseMove, Button Clicks, etc...). Basically all the functionality of a CWnd in a control on a WPF form?
The UIElement is the lowest level element that supports input and drawing. Although, using WPF, you really have to do a lot less manual drawing. Are you sure that you need to do this? Also, the scroll bar will never be inherit in your element. If you need scrolling behavior, just wrap your element in a ScrollViewer.
UIElement is the place to start and OnRender is the method to override.
Be warned that WPF is heavily geared toward composing UI as opposed to the WM_PAINT ways of Win32. Unless you are creating new low level primitives there is almost always a more productive alternative.