I am trying to make a program which plays video and receives user input on specific frames. i need to make a click event for the axvlc video player. Is this possible?
my program contains an instance of the VLC ActiveX Plugin in a windows form in visual studios.
I want, while the program is paused, for the user to be able to single click a point on the frame, trigger an event, add the location of the mouse to a list.
otherwise, i have considered rendering a bitmap of whatever frame it is on while paused so that i can add click events to that. but i would very much like to avoid that solution as it would complicate what i am doing.
I found a tremendously helpful control in this question.
Making a control transparent
the top answer has code for a control that supports real transparency even on top of video. this is perfect.
Related
I need to write a text recognition (from image) application. The main idea is that while my application is running, I may have the need to transform some text of an image into manageble text. So, in this case with the mouse I need to draw a square around the area that i need to capture and the software must convert the content of the extracted picture into text.
I solved the problem of image recognition. I also find a very easy way to capture from screen.
What I need to do now is be able to select with the mouse the interesting area that is over an other running opplication (for example over a webpage or over an image opened in Paint). That must be like the screencapture on windows7, you create a selection of the screen and this is saved like a picture.
By looking around, I didn't find anything and I don't knwo where to start.
Many thanks
You can achieve that using either a 'tricky' easy way or a real but difficult approach.
The tricky way
Screen Recorder applications usually use this approach:
Whenever user wants to select an area, you display a full screen border less Window with 0% opacity, then user attempts to select the screen area, and he is actually selecting your Window area, so you can receive mouse events and display/draw a rectangular shape to show the selection area to the user.
In this approach, the program needs to know when to display the Window and when to hide it. This can be done by for example defining Hotkeys for capturing:
Program registers a hot key using RegisterHotKey to Windows.
User presses and holds that hot key
Program displays the tricky Window
User selects the interested area, program receives that area using mouse events of the tricky Window
User released the hot key and program hides the Tricky window.
The real way
Using this way, you need to set a message hook in order to receive mouse and keyboard events while user is interacting with desktop not your program. This is not an easy to accomplish approach and I recommend you the first one.
I tried writing code several different times, but I came to an error with each one.
Basically, I'm trying to make "windows" similar to say Explorer, Paint, MediaPlayer, where you could drag then around, interact with them, minimize and close. Of course, if you clicked on a window, the one below it (they can overlap) shouldn't get affected.
I know how to do this, I have a list of the class I call Window, loop through it, and I only interact with the first window to contain the location of the mouse-click. This way, other windows overlap won't get affected.[1]
Next, I had to make it so that two buttons that are overlapping don't get activated when the user clicks in the "intersection of both buttons." I handled this by using the same method I used above.[2]
But the problem I'm facing now is that, if I hold the left click, but then I decide not to click a button, I drag the mouse away from the button, and release the left click, so that the button-click event won't be activated. But, when I remove the mouse from the boundaries of the button, and say, into another.. the new button get activated. Which it should not.[3]
My set up is like this:
I have a class called Window.
In Window, I have a list of the class called Interface (similar to the Control class in WinForms).
And each Interface has a struct in it that contains 4 bools, if the left/right is currently down, and if they were down in the previous processing. (prevLeft, prevRight, currLeft, currRight)
So, I'm ready to discard that (I have not yet, so I still have the source code), but I need a good structure for making an object-oriented type of application. However, I am not using WinForms. I need help with the structure alone, so no actual code is necessary, description is enough. I need to avoid the 3 problems I mentioned above.
Creating your own Window Manager is not an easy task. I know it because I'm making one too ;)
You can use an existing, though maybe not the best solution, like for example Nuclex.UI, which I personally rejected when I first saw it, but if you're not dead set on making your own WM, I suggest to use that or hybrid WinForms-XNA approach.
But if you're really dead set on implementing a custom Window Manager, you have to understand how any other WM works. Since we're talking about XNA, it means Windows, and that means Windows Explorer, which is a great thing to learn from.
You have to recognize how the simplest things work, and it's really not so hard. The hard part is figuring out what logic is updated when, and how to not spend all the CPU on only UI updates. Let me just give you a few hints on how to solve the problems you mention in your question.
To keep track of all windows, I'm using a Dictionary<string, Window>, where Window is a custom class, and the string is its unique name for rare cases where I have to call windows by name. Think of it as a window GUID or Handle. But you can just make it so that a "Form" can only appear once, and store all references in static variables.
To make WM understand what control you're clicking I use rectangles and check if they contain a Point which is at Cursor coordinates and has {1; 1} pixel size, which is probably about the same way it's done in Windows Explorer. To do that your WM needs to know in which order to update the active windows. Usually you'd want to start from the topmost window and continue towards the end of the list of active windows. For that you can just iterate through the list with a foreach loop.
But that's not all, because every window itself is a Container, which means it contains other controls, some of which may even be Containers themselves, like WinForms Panel class. This means you have to iterate through each of the Windows' Children controls. The update order should make sense too - update from the topmost child to the bottommost, recursively for Container controls, in case they also have Containers in them. This basically means you'd want to implement a recursive GetAllControls() method for your WindowManager class that would iterate through all Containers and return a list of all Controls.
Drawing all those Controls should be done in reverse order of updating them, so you can just GetAllControls().Reverse() and iterate through that in a foreach loop.
Where to draw and what to update depends on all the parent containers the current container has and their combined offset from the top-left corner of the game window. I solve this by storing a ParentContainer reference in all children controls to get the appropriate DrawRectangles and update areas via recursive properties.
When you click somewhere on the screen and a click is registered on a Control, make the WindowManager remember that (bool clickRegistered) and not run any OnClick events on any underlying Controls.
Windows Explorer remembers the control you clicked and will activate its OnRelease event if the cursor is then released in the update area of the very same control. So basically Windows Manager only does something when you release the mouse button. You can make your WindowManager and Controls to handle click events differently, like firing an event right after you press the mouse button, i.e. OnMouseDown. But remember that Microsoft aren't noobs and there's a reason for that behavior in Windows Explorer, and it's because if you accidentally press a mouse button somewhere you didn't intend, you can still fix it by moving the cursor outside the pressed control's update area and not run its action.
At this point you might be thinking "Is it really worth implementing all this?" For me the answer was "maybe", because I was a total noob in both C# and XNA at the time I started, and now I know my game, which was originally supposed to use some Window Manager, is going to benefit from my own WM implementation far more than from ready third-party solutions. And besides, it's a great exercise in logic and programming.
But if you'd like to think of yourself as a game developer, you should think in terms of reaching your goal as quickly as possible, i.e. actually making a game, and not the game engine. So in this case, better make use of existing solutions and start selling your product.
Instead of having the structure with the 4 booleans (similar to xna), how about you make a way to tell where the mouse "is." So in a sense, the mouse is in Window number 5 which is Paint, and the user is holding the mouse down on interface/control number 2 which is a button.
That sounds like it could work.
I am currently working on a desktop C# WPF application where the goal is to make it look and feel like a "real" Windows Store App.
I want to add an appbar that should be shown when the user swipes up from the bottom. To do this in a normal app you just position your finger outside the screen area, and swipe up.
But if I do that in a fullscreen WPF program I don't receive any TouchDown or TouchMove events - probably because the finger is already down when entering the actual screen area.
I have tried with the Manipulation framework also, but same result here. Even when I hook directly into the message queue using WndProc or other hooks I get no events at all.
The funny thing is that I can see the "touch cursor" move around the screen, so at least something in the underlying framework is notified.
Does anyone have an idea how to do this?
p.s. It is not an option for me just to use a windows store app instead, because of hardware connectivity issues ;-)
You will need to keep track of the cursor location coordinates, and see when the cursor (swipe) starts at the edge of the screen and moves in. When that triggers (with whatever trigger you want, distance covered most likely) you can fire up your Appbar.
There was a similar question asked on MSDN:
https://social.msdn.microsoft.com/Forums/vstudio/en-US/d85dcde7-839a-44d3-9f2a-8b47b947576c/swipe-gesture-and-page-change?forum=wpf
I need to create a application which is similar to those we will get when we buy a laptop. It will be visible only when the mouse pointer reaches the top of the window. So how can I able to do this using C# 4.0 ?
http://www.notebookcheck.net/uploads/pics/win2_12.jpg
this link u can see the application. I need to create such type
Any idea pls share. Thanks
I suppose there are several different ways to achieve this effect:
You can place part of the window of your application above the visible screen, so only a part of it is visible (let's say you can see only it's bottom). Then you need to handle events when mouse enters (MouseEnter) and leaves (MouseLeave) the form to move the form up and down.
You can use a background thread to call GetCursorPos method at a set interval (i.e. each 500ms) second to check where currently the mouse is. See this link for more information about it and a sample code: http://www.pinvoke.net/default.aspx/user32.getcursorpos.
(If you need only to check the mouse position, you can use a timer to simplify you application.)
When you hit what's possible with C#, you can always start invoking native code - such as the windows API. Since you don't ask a specific question, I'll leave you with:
Position your app where you want it to appear and hide it.
Capture mouse position with windows api (see this SO answer)
When mouse is at screen corner / top, etc; make your app visible.
Now make sure all this works with dual screen setup, and you are done.
I have a Silverlight control containing an image. I want the user to be able to drag the image out of the Silverlight application and drop it anywhere they would be able to drop an image. For example, to the Desktop or to a PowerPoint slide or Word document. Everything that I have read thus far says it cannot be done but I find that hard to believe. I'm very new to Silverlight and RIA development so any help would be much appreciated.
Below is the code sample in my WinForm Form but the drag never starts.
string[] aString = { imagePath };
DataObject data = new DataObject(DataFormats.FileDrop, aString);
data.SetData(DataFormats.StringFormat, imagePath);
DoDragDrop(data, DragDropEffects.Copy);
Well the trouble is that a drag operation in Silverlight doesn't have simple access to anything outside the browser (by design). Depending on the user's settings you even have to get explicit permission for clipboard operations and sandboxed temporary file storage. This really sounds like a task better suited to a WPF application (perhaps with web deployment?) or some other desktop application technology.
However, that being said here are some things you could try/consider:
Silverlight/Javascript/ActiveX combination hosted in Internet Explorer
Silverlight 5 "Out of Brower" & P/Invoke (I heard P/Invoke will be supported when Silverlight 5 comes out)
Silverlight connecting to a web service running on the same computer (crazy, but you didn't ask for "not crazy", you asked for possible)
I am not very familiar with drag and drop in the Win32 API so it would take a lot of research and experimentation before I could confirm that this was even possible (and I can already tell you it isn't practical).
Edit: Based on the extra information you provided about the question I suspect it is possible to do what you are attempting. First, are you using WPF or WinForms? I assume WPF but one of your comments says WinForms. I wasn't very familiar with WPF drag/drop operations, but having looked into it, I think your code is on the right path. I created a WPF application and initiated a drag during a KeyDown event. This meant that the mouse button was not necessarily pressed. If I initiated the DragDrop while the button was down it worked. If I initiated while the mouse button wasn't down, I had to push the mouse button down and the drag operation would start (this was unexpected since I assumed the mouse would have to already be down). If I pressed the mouse down outside the application, then gave the WPF app focus (ALT+Tab), then initiated the DragDrop while the mouse button was still down, it didn't work. I got a reference to the MouseDevice and checked the LeftButton property, and the state was showing as "Released" even though the button was still being held down. It seems the key here is the way drag/drop interacts with internal mouse state. You might have to find a way to set the mouse state (maybe with the UI Automation API?). At this point it should be painfully obvious that this whole thing is a hack (even though it is probably possible to get it to work somehow).
The solution we came up with was as follows. The RIA i.e. Silverlight sends a message to our Desktop application WinForms with the path of the image to drag along with the bounding rectangle in screen coordinates that we want to start the drag from. The Desktop code creates and places a Panel over the area that we want to drag from. This panel is where we use DoDragDrop to initiate the native drag when the user left clicks. Since this panel is placed outside and above the silverlight control, everything works perfect. Sandbox defeated.
I have been working on some Silverlight apps for the past few months and fully investigated your exact requirements only to find it was not possible. I believe you can drag from the file system, from Silverlight control to control, but not to the file system.
Does Silverlight 4 support drag and drop from app to desktop?
http://msdn.microsoft.com/en-us/library/dd772166%28v=vs.95%29.aspx