Apex Reference Guide
j
No Results
Search Tips:
- Please consider misspellings
- Try different search keywords
Canvas Exceptions
The Canvas namespace contains exception
classes.
All exception classes support built-in methods for returning the error message and exception type. See Exception Class and Built-In Exceptions.
The Canvas namespace contains this exception:
| Exception | Description |
|---|---|
| Canvas.CanvasRenderException | Use this class in your implementation of Canvas.CanvasLifecycleHandler.onRender(renderContext). To show an error to the user in your onRender() implementation, throw a Canvas.CanvasRenderException, and the canvas framework will render the error message to the user. This exception will be managed only within the onRender() method. |
Example
The following example implementation of onRender() catches a CanvasException that was thrown because a canvas
URL was set with a string that exceeded the maximum length. A CanvasRenderException
is created and thrown to display the error to the
user.
public class MyCanvasListener
implements Canvas.CanvasLifecycleHandler {
public void onRender(Canvas.RenderContext renderContext) {
Canvas.ApplicationContext app = renderContext.getApplicationContext();
// Code to generate a URL string that is too long
// ...
// Try to set the canvas app URL using the invalid URL string
try {
app.setCanvasUrlPath(aUrlPathThatIsTooLong);
} catch (CanvasException e) {
// Display error to user by throwing a new CanvasRenderException
throw new Canvas.CanvasRenderException(e.getMessage());
}
}
}