I want to achieve the following with a WPF application (in a certain area/defined area):
When clicking and holding on the app, you can draw a square
You can do this as many times, but not overlap any squares
You can drag squares around the application
What do I need to achieve this, I assume a bunch of onclick/onmove's. Is there an easier way, such as using canvas? Any insight would be great.
You will have to use a canvas if you want the squares to appear where the user clicks and drags.
The mouse down event would define one corner and the mouse up the second. You'd have to constrain the movement of the cursor so that the x and y dimensions of the rectangle were the same.
On each mouse move event you'd have to check if the cursor were over one of the existing squares and prevent the square growing any further.
For the dragging of existing squares modify the mouse down event to check what's under the cursor. If it's the canvas start the square drawing mode, if it's a rectangle (square) then start the dragging mode. Again you'd need to use the mouse move event to check that the square doesn't intersect with any existing squares.
There's a code project article describing how to drag elements inside a Canvas: Dragging Elements in a Canvas
Speaking of ChrisF's mentioning of using a Canvas, I would suggest you use DragCanvas (found in the article)
Related
In WPF, I have a custom "toolbox" which consists of Label controls and some vector icons docked to the left of the screen.
In the center, I have a Canvas control which I eventually am going to need to serialize out the relative coordinates (for other platforms) for this "designer surface".
Basic question, I can drag/drop controls from this psuedo-control box onto a Canvas but I need to know how to place this WPF control properly in the canvas, under where the mouse pointer is, realtive to the Canvas and not the screen or main Window.
What are the functions that needed to be called so that I can ensure that if I drop a Button control at 10%, 20% of the canvas, I get an actual location back and the button drops where expected?
Mouse events provide a Point structure.
Converting of positions can be done by Control.PointToScreen and TargetControl.PointToClient.
I want to write a GUI editor in C# for AutoIt, but I am not good enough with C#. I want to draw a square (focused) around an object when any object in the GUI is pressed. Like this:
Is there any library to make easier to write this kind of thing?
Square is drawn with one of DrawRectangle functions. Each of them requires a pen. Usually we use ordinary solid pen, but you need a pen with changed DashStyle property. For dotted lines change this property to DashStyle.Dot. You can also experiment with DashPattern property.
To draw little squares around the big square you need one of FillRectangle functions. Each of them requires a brush. You need a white brush, which is conveniently predefined for you to use. After filling a rectangle, you have to draw a rectangle over it with the same dimensions. These two functions together give an impression of empty and lined rectangle.
To make little squares a little rounded, like they are in the image, you have to change a pen parameter used when calling DrawRectangle. Experiment with LineJoin, and other properties of the Pen class.
This is very hard for a simple question that you posted. There are a lot of things that you need to take care of.
First I would suggest to make a class that will have a Rectangle property since you can't subclass Rectangle because it is a structure.
You will need to handle the drawing, that is the simplest task as mentioned in the other answers so I'm not going to be specific about that.
Since you have small squares that indicate that the rectangle can be resized, you will have to implement method that checks whether the mouse point is within the big rectangle or some of the small suqares. In this case you should change your cursor to indicate the possibility of resizing.
To handle moving (but not resizing) of the rectangle you will have either to make a new small square with the sign for moving in all directions or you will handle that using cursor when the mouse position is within the Big Rectangle.
The main problem is identifying what to change when resizing, you have two options:(1) to change Location and Size properties or to change X, Y, Width and (2)Height properties of the rectangle. For instance, when you are moving top-right corner you should change both Location and Size in first case or Y and Width is you are using second option.
When you move the mouse while it is clicked, you should watch out in which direction mouse moves. If you split the viewport in quadrants where the center of your rectangle is the center of the Decartes coordinate system, by identifying in which quadrant is the mouse you will know which corner (or edge) of the quadrant you need to move.
Each mouse move will have to call Invalidate() because you can't use Xor like in C++. Therefore, when your Rectangle is displayed, you should be in a special mode where everything that not moves (not changes, everything except Rectangle and selected control) should be drawn to the Bitmap that is used between two redraws and you should only draw what is moving.
As you can see, there is a lot of things that should be taken care of. You should start with this only after you are sure that you have already implemented other parts of your program.
I just want to know how can i drag and drop a line which was created dynamically at runtime (mouse draw line) in c# . The dynamic line was placed over a panel.
I have used two ways in the past:
On MouseDown calculate the distance between the line and the mouse cursor. If it is within a couple of pixels start dragging. While the MouseButton is down respond to the MouseMove by translating the startpoint and the endpoint of the line over the same vector (current mouse position - start dragging mouse position)
On MouseDown test the color of the pixel under the mouse cursor to see if it is over the line. If so do the same dragging as above.
The tricky thing is that option 1 is hard when there are multiple lines that are close and you need to find out which line needs to be dragged
Option 2 is hard when the line is very thin.
Another way is to draw a thicker line on an invisible bitmap when a line is drawn and test the pixel on the invisible bitmap. That way you can give a bit more tolerance AND you could give each invisible line a color that is distinct so it is easier to identify what line has been clicked.
Does this make sense?
I am creating shapes on a wpf using a Canvas. I have created by C# code some Rectangles, each one of which is assigned with three circles and a TextBlock. I want now to make them move on the Canvas by a mouseEvent , in other words to drag them with the mouse and to move them on the Canvas. How is it possible to manipulate each Rectangle with the circles and the TextBlock as a compact group?
It is required, when the user clicks on the Rectangle to transfer it with its contents. However, the circles and the textBlock have their own coordinates, so if not grouped they stand still. How can I get over this?
Put the rectangle and everything else in a grid or another canvas, as described in this related question of yours: Drawing circles on a Rectangle
This is basically a user control composed of the rectangles, circles, and textbox, and you just allow that whole user control to be moved around, rather than the constituent parts.
If you don't want to add another layout panels try to apply the same transform to all elements you want to move, it's not so heavy solution.
The scenario is that i want the user to create a shape in a small panel that opens (the added shape can later be placed on the canvas), but for a better reference, i want the user to be able to move the semi-transparent panel somewhere on the canvas and then draw with the accurate reference.
Please tell me:
Which panel type to use
How to make it moving by clicking the mouse on the move button (not the whole panel as dragging will be used for drawing lines) and move it around.
How to make it semi transparent.
How to make it appear and disappear (this should be pretty simple)
How to somehow limit its movement inside the canvas so it cannot move on the ribbon
And I really really hope there will be something built-in in WPF that i'll be able to use, and i will not have to do it the hard way i.e. create a rectangle, and do customized hit testing on it to allow the user to draw on top of that rectangle, make that rectangle transparent, and add graphics items for the buttons and controls on that rectangle "panel".
I am asking this because i have never seen such feature in any Windows application and i have no idea what to use for this purpose and how to implement it. The closest thing to what i want is in Adobe Acrobat Pro, which is the small preview of the page that appears when i double click with the middle mouse button. It doesn't move, nor it is transparent or can be drawn upon, but scale and shape wise i want something similar.
You should be able to place a second Canvas inside of your main canvas, and place whatever UserControl you'd like with your "view" inside of it.
You'll have to handle the mouse click/drag for moving it around yourself, but otherwise, it should be very straightforward.