What i want to do:
How my program looks like:
So currently i have a table which contains elements. I thought the right idea would be maybe work with lines and circles to draw graph? Or is there a better alternative? Also the main question here is how to set a layout, so if there's an element number one it has a circle under it and if the element is 15 it has an element under it. My thought is for every circle to has it's own row, if one has been placed the next one is 10px below etc. Although still the question remains about layout, any pointers?
E:/
I came up with a little idea to use Line Chart, but the Line Chart doesen't allow me to manipulate it with the way i want. It will just create lines in ascending order but i would like to move from point one to point five and then to point 2 (as shown in the chart above with different elements but the idea is same).
Related
This is perhaps more of a whine than a question, and I'm aware there's a workaround to the problem described in this post. But I have a situation where I have to add components to a GridLayout, possibly enlarging the grid as I go; but the components don't get created and inserted in a nice neat order; and I don't know when I'm done being handed components to insert into the grid. In other words, in a 3x3 grid I might get handed a component to put at (0,2) and then another at (1,0) and then one at (0,0). And then I might get one at (5,2) and need to enlarge the grid. And then I might get told to replace the line at (0,0) with something else.
I understand that there's no way to say "put a component at x, y". I get that I'm going to have to build a 2D array to hold my components and then empty and refill the grid from the array, each time it changes, which is going to be quite often in several large grids, so I'd rather not. I get that life is like that and the language is the language and who am I to question why.
But I'm really curious. This seems like the most basic of operations for a grid to support. Not having it feels like I'm working with a spreadsheet that only lets you enter values in order from left to right - it's simple madness.
I haven't taken apart the source code for GridLayout, but any naive understanding of how it "must work" makes me think add(component, row, col) should be trivial to implement. It must not be, because GridLayout isn't exactly new and I can't believe I'm the first to think random access to a grid is a good idea. So it must be really hard. But why?
I realize understanding why the internals of GridLayout can't support this, doesn't solve any real problems, except the problem of me unable to stop thinking about how fundamentally weird the restriction is. In the end I'm going to end up with a parallel array, or messing with the more complex GridBagLayout, unless someone knows a better way. But I just want to know why I have to.
Why not approach the problem from a different angle:
Create your grid using GridLayout
Fill the grid with empty JPanels
JPanels that each uses a BorderLayout
Keep these JPanels where they are
But swap the JPanels that they display within them in each of their BorderLayout.CENTER positions
Alternatively, you could have them use a CardLayout, but the effect would be the same
I've set up a grid of 52x52 black tiles, and now I want to create a method which will remove 52 black tiles and replace them with grey squares.
I do not want to apply these replacements purely at random, and I also do not want grey tiles to replace other grey tiles. My goal is to have an initial point which is randomly chosen to be replaced (which I have already done), then the next replaced tile is to be randomly selected from one of the 8 adjacent black tile surrounding that initial grey tile. When that is done I want one of the black tiles adjacent to the newly replaced tile to be selected and replaced, and so forth until I get 52 replacements.
I've being mulling it over for a little while now, and I can't figure out a way to pull it off. I can't lay every possibility out in a switch statement, as doing so would obviously be an impossibly lengthy feat. I considered trying to create an ArrayList to memorize the coordinates that have already been input which can be checked against whenever my program has selected a place to put a new tile, but I wasn't able to figure out how to store and compare the coordinates. Beyond that no solid solutions come to mind, just slight permutations of what I have already mentioned.
Do you have any advice on what course of action I could take here?
I'm surprised to see that this hasn't been done, or at least my research says so.
I have a Canvas with RowLayout and a bunch of Labels.
The title is pretty straight forward: I want to reorder my labels using DND.
Please don't tell me I have to engineer my own algorithm for calculating bounds and sizes and stuff like that.
Later edit:
I'm considering using Zest, but again, I can't find any example where graph nodes are snapped to eachother.
I did something like this about a year ago.
My method of solving this problem was to use a data model to hold the label information. Use the canvas.getChildren() and search for a separator composite between each object or the label that you dropped on top of. When a drag and drop operation was completed you would search for the item that you dropped on and move the reference to the appropriate position in the model. Then reset the information on each label. Only requirement to do this is to keep a data structure with the label info and a reference to the canvas.
So I'm doing the project of an introduction to Java course and it seems that I chose something that goes way beyond what I'm able to do. :P
Any help would be greatly appreciated. This is what I'm having problems with:
You have a cursor that is controlled by a player (goes forward or
turns 90°) which leaves a colored line as it goes. If you manage to go
over your own line and close a polygon of any shape (only right angles
though), its surface changes color into the color of your line.
I can detect when this situation arises but I am kind of lost as how to actually fill the correct polygon just closed. I can't seem to imagine an algorithm that would cover any case possible.
I looked at the Scanline fill algorithm but I think it would start having problems by the time there are already some polygons already filled in the map.
The Floodfill algorithm would be perfect if I had a way of finding a point inside the polygon, but, as there are many different possibilities, I can't think of a general rule for this.
I'm using an array 2x2 of integers where each color is represented by a number.
Does anyone have an idea on how to approach this problem?
If you can detect the situation then this can be solved in very simple manner. The question is which point to choose as start point for floodfill. The simple answer is: try all of them. Of course it makes a sense to start only with points adjacent to the one where your cursor is located. In this case you will have at most 8 points to check. Even better - at least 2 of them are definitely painted already if current point forms a polygon.
So you have 8 points to check. Launch floodfill 8 times starting from each of those points.
Two things which you probably should keep in mind:
You should try filling the area in cloned version of your field in order to be able to get back if floodfill will not find a polygon.
Launching floodfill second time and later you should reuse this cloned version of your field to see whether it was filled there. This will allow you to check every point at most once and this will make your 8 floodfills almost as fast as 1 floodfill.
Check this question, using Graphics2 and Polygon to fill an arbitrary polygon: java swing : Polygon fill color problem
Finding out whether a point is inside or outside a polygon: http://en.wikipedia.org/wiki/Point_in_polygon
Make sure you use double buffering. If you set individual pixels and don't use double buffering the component may redraw after every pixel was set.
I am making my own class diagram app in Swing/AWT but i stopped at this functionality:
I want to draw a line between the Class rectangle that already selected and to the target Class rectangle, but line has a feature which is whenever i move one of the rectangles the line that join them get bend in a straight fashion following the moving rectangle , i hope the following picture demonstrate what i want to achieve:
A general guideline or a sample code is highly appreciated
I don't know Java, but the steps you could follow are these:
Find the middle of each line of the rectangles (should be easy, just avarage x1+x2 and y1+y2)
Determine the edges that are closest to each other using Pythagoras formula on the points you got in the previous step.
Start drawing a line starting at xa,ya (first point you got in the step above), and draw it in the direction away from the rectangle. You should know this direction, because you can know the line segment this point is on.
Do the same for xb,yb (point on the second rectangle). If the lines are in opposite directions, you should draw them to halfway xa-xb or ya-yb (depending on if you're drawing horizontally or vertically). If they are perpendicular (is that the right word?) you should draw them to the point where they cross, so you draw the line from xa,ya to xa,yb or xa,ya to xb, ya, depending if you draw the horizontal or vertical line.
There should be some additional check to see if the rectangles overlap. You should not draw lines in the same direction for example. Maybe it would suffice for you to draw just a diagonal line between the two points in those cases where you cannot determine how to draw these straight lines.
For the implementation you could build a line class that uses the observer pattern to listen to the two rectangles it follows, so it can update itself whenever one of them moves or resizes.
http://java-sl.com/connector.html
Hope this helps.
Try with observer pattern. All lines that are connected with a moving object should be notified with new position of the object and 'bent' properly. Of course, first implement some logic that will connect 2 objects.
try creating a class named "ConnectingLine" or similar. this class will then have several segments (that's the name of these line parts in dia, which is currently my favorite uml modeling tool) which will be calculated one by one. you'll have a sepaparate class for this of course ;) called maybe "LineSegment". i think this should make it easier for you to perform the mathematical calculations required to perform this task.
this could also enable making segments "auto routed or not" easy d(^_^)b