Draw a rectangle on an image in gui with mouse hover

5 次查看（过去 30 天）
Abdulllah
Abdulllah 2019-1-11
评论： Abdulllah 2019-1-14
This question has two parts.
First I want to draw a rectangle on an image in gui only when the mouse hovers on the image. Secondly, if the user clicks the image execute some statements. Right now, I can only draw the rectangle on the image in following manner,
axes(handles.axes1);
[r,c,~]=size(Image);
rectangle('Position', [-2,-2,c+4,r+4],'EdgeColor','r');
  3 个评论
显示 1更早的评论
Abdulllah
Abdulllah 2019-1-11
Thank you for reply. I want to draw the rectangle when mouse hovers on the image and when the mouse is out of image then rectangle should get removed. Like mouse on image, draw rectangle on image, mouse not on image no rectangle.
Then when the mouse is on the image and there is a left click on the image then I want to execute some other set of statements. May be you can call it a function
call_when_image_clicked()
Abdulllah
Abdulllah 2019-1-11
I am sorry, I forget to reply second question. These statemens drawing the rectangle on image ver well.
[r,c,~]=size(Image);
rectangle('Position', [-2,-2,c+4,r+4],'EdgeColor','r');
New Bitmap Image.bmp

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

Kevin Phung
Kevin Phung 2019-1-11
编辑：Kevin Phung 2019-1-11
Hello,
You can use the 'WindowButtonMotionFcn' property of your figure,
f = figure;
set(f,'WindowButtonMotionFcn',@cursorPos)
with the callback function retrieving the position of your cursor:
function cursorPos(my_fig,event)
pos = get(my_fig,'CurrentPoint');
You know the position of your image with:
image_pos = get(image_handle,'Position')
so you can add the logic where if the position is within the bounds of the image: draw a rectangle; else, delete existing rectangle.
If you call the handle of your figure and see all the properties, you can see the various types of callbacks your function can trigger, for example:
WindowButtonDownFcn: ''
WindowButtonMotionFcn: ''
WindowButtonUpFcn: ''
WindowKeyPressFcn: ''
WindowKeyReleaseFcn: ''
WindowScrollWheelFcn: ''
------
The 'WindowButtonDownFcn' should be used for:
set(f,'WindowButtonDownFcn',@call_when_image_clicked)
Hope this helps!
  1 个评论
Abdulllah
Abdulllah 2019-1-14
Hello, Thank you for your reply. I can now WindowButtonMotionFcn and can draw the rectangle. but I am I unable to find the postions of the image. If I find position of the image using
get(eventdata.axes1,'Position')
I get values in points (). and if I use
image_pos = get(eventdata.figure1,'Position')
I get value in even -ve (1084.2 -55.8 2033.6 1115.2). I dont know why negative,
I am using this logic now to draw the rectangle under the WindowButtonMotionFcn.
pos1 = getpixelposition(eventdata.axes1,true)
currentp=src.CurrentPoint
image_pos = get(eventdata.figure1,'Position')
x1=680;
y1=1046;
matlabImage = imread(strcat(num2str(randArr(3)),'.tif'));
[r,c,~]=size(matlabImage);
x2=1397;
y2=512;
if ((currentp(1)<x2&&currentp(1)>x1)&&currentp(2)>y2&&currentp(2)<y1)
% axes(hObject.figure1);
rectangle('Position', [-2,-2,c+4,r+4],'EdgeColor','r','LineWidth',3);
else
rectangle('Position', [-2,-2,c+4,r+4],'EdgeColor',[0,0,0]','LineWidth',3);
end
I need to determine the values of x1,y1,x2,y2.

请先登录，再进行评论。

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Images 的更多信息

标签

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by