Qt validating user input

Here are some examples: For an editable combobox that accepts URLs, any well-formed URL is Acceptable, " is Intermediate (it might be a cut and paste operation that accidentally took in a comma at the end), the empty string is Intermediate (the user might select and delete all of the text in preparation for entering a new URL), and " is Invalid.fixup() is provided for validators that can repair some user errors. QLine Edit, for example, will call fixup() if the user presses Enter (or Return) and the content is not currently valid.

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The values the user enters in the wizard are assigned field names.

Field name and value pairs are then passed to the file creation process.

Q_ASSERT(res); // Attach the validator to the text field and add the label and text field to // the top-level container my Text Field-// Create the UI controls Page *root = new Page(); Container *top Container = new Container(); Label *my Label = new Label("Type a username (10 characters maximum)."); Text Field *my Text Field = new Text Field(); Button *validate Button = new Button("Validate"); // Create the validator Validator *my Validator = Validator::create() .error Message("Your username must be 10 characters or fewer.") .mode(Validation Mode:: Custom); // Connect the validator's validate() signal to a slot function.

Q_ASSERT(connect Result); // Connect the button's clicked() signal to a slot function.

When the user taps Enter on the virtual keyboard, your app updates the list with the new entry.

You can use the input property (and its associated class, Depending on the text that your app is designed to handle, you might want to make sure that the text conforms to a certain set of criteria.

For example, an ISBN validator might want to delete every character except digits and “-”, even if the result is still not a valid ISBN; a surname validator might want to remove whitespace from the start and end of the string, even if the resulting string is not in the list of accepted surnames.

The QValidator class provides validation of input text. Two subclasses, QInt Validator and QDouble Validator, provide basic numeric-range checking, and QReg Exp Validator provides general checking using a custom regular expression.

For example, you could ensure that a username contains only letters and numbers, or you could enforce a minimum length requirement for a password.

If you use a // Create the UI controls Page *root = new Page(); Container *top Container = new Container(); Label *my Label = new Label("Type a username (10 characters maximum)."); Text Field *my Text Field = new Text Field(); // Create the validator Validator *my Validator = Validator::create() .error Message("Your username must be 10 characters or fewer.") .mode(Validation Mode:: Immediate); // Connect the validator's validate() signal to a slot function.

File creation can happen in the following ways: determines whether the script module is added.