如何在Matlab App Designer中通过独立图形窗口获取鼠标点击点

Absolutely, you can totally create a standalone, non-UI figure window in MATLAB App Designer to display graphics and capture mouse click positions—let’s sort out that blank window issue you’re facing right now.

The Core Issue #

Your current code is probably creating the blank standalone figure but not directing your plot to it; instead, the graph is defaulting to App Designer’s built-in UI axes. The fix is straightforward: explicitly create a traditional figure() window, then draw your graphics onto that window, and attach the mouse click callback to it.

Step-by-Step Code Example #

Here’s how to implement this in your App Designer app:

1. First, add a property to your app (go to the "Code View" > "Properties" tab) to store the standalone figure—this prevents it from being automatically garbage-collected:

properties (Access = private)
    StandaloneFig % Stores the standalone figure handle
end

2. Add a button callback (or trigger this logic from any UI event) to create the figure, plot your data, and set up the mouse click handler:

function OpenInteractivePlotButtonPushed(app, event)
    % Create a standalone figure window (not a uifigure)
    app.StandaloneFig = figure(...
        'Name', 'Interactive Plot Window', ...
        'NumberTitle', 'off', ...
        'Position', [100 100 800 600]); % Set window position/size

    % Plot your data DIRECTLY onto this standalone figure
    x = linspace(0, 2*pi, 200);
    y = sin(x) + 0.1*randn(size(x)); % Example data
    ax = axes(app.StandaloneFig); % Get the axes of the standalone figure
    plot(ax, x, y, 'LineWidth', 1.5);
    xlabel(ax, 'X Axis');
    ylabel(ax, 'Y Axis');
    title(ax, 'Click Anywhere to Capture Coordinates');

    % Attach the mouse click callback to the figure
    set(app.StandaloneFig, 'WindowButtonDownFcn', @(src, evt) app.CaptureMouseClick(src, evt));
end

3. Create the mouse click callback function to handle clicks and retrieve coordinates:

function CaptureMouseClick(app, src, evt)
    % Get the exact click coordinates from the figure
    clickPoint = get(src, 'CurrentPoint');
    xClick = clickPoint(1, 1);
    yClick = clickPoint(1, 2);

    % Option 1: Display coordinates in your App Designer UI (e.g., a text field)
    app.ClickCoordinatesEditField.Value = sprintf('Clicked at (%.2f, %.2f)', xClick, yClick);

    % Option 2: Mark the click position on the standalone plot
    ax = src.CurrentAxes;
    hold(ax, 'on');
    plot(ax, xClick, yClick, 'ro', 'MarkerSize', 8, 'MarkerFaceColor', 'r');
    hold(ax, 'off');
end

Key Fixes Explained #

• By creating a figure() (not uifigure()), you get the traditional MATLAB graphics window that supports full interactive operations.
• Explicitly specifying the figure/axes as the parent for your plot() command ensures your graph renders in the standalone window, not the App Designer UI.
• Storing the figure handle in an app property keeps the window open and accessible for callbacks.

Bonus Tips #

• If you want to handle window closure cleanly, add a CloseRequestFcn to the figure to reset the app property:

  set(app.StandaloneFig, 'CloseRequestFcn', @(src, evt) app.CloseStandaloneFig(src, evt));
  

  Then define the closure callback:

  function CloseStandaloneFig(app, src, evt)
      delete(src);
      app.StandaloneFig = [];
  end
  

• Avoid mixing UI axes and standalone figure axes—always specify the parent object for plots to prevent unexpected behavior.

内容的提问来源于stack exchange，提问作者Qiana Curcuru