Usage

Using this library boils down to this steps

• Create a validator object

Validator validator = new Validator();

• Add validation checks to the validator

// the editText objects to validate
EditText nameEditText = (EditText) editText.findViewById(R.id.name);
Spinner ageSpinner = (Spinner) editText.findViewById(R.id.spinner);

// ... using check objects
validator.addCheck(new NotEmptyCheck(nameEditText, "name cannot be blank");
validator.addCheck(new NotEmptyCheck(ageSpinner, "age cannot be blank");

Learn more about available checks

• Validate

To run the validations involve the validators validate() method.

validator.validate()

This method returns true if the validation passed or false if the validations failed.

Handle the errors

Incase of validation failure, the validation errors can be accessed via the getErrors() method.

This library comes with a convenience class ErrorRenderer, which can be used to easily display the validation errors.

• Displaying errors.

// the layout where we display any validation errors
LinearLayout errorSpace = (LinearLayout) findViewById(R.id.error_base);
errorSpace.removeAllViews();// clear space first

if (validator.validate()) {
    // .. code to perform if validation passes
} else {

    // show the errors if validation failed
    // we use the renderer class to handle the display
    ErrorRenderer errorRenderer = new ErrorRenderer(this, validator);
    errorRenderer.render(errorSpace);
}

• Using ValidationListener to handle errors.

This version of validate() accepts a ValidationListener which has onValidationSuccess invoked when validation is a success. onValidationFailed invoked when validation fails methods.

// the layout where we display any validation errors
LinearLayout errorSpace = (LinearLayout) findViewById(R.id.error_base);
errorSpace.removeAllViews();// clear space first

validator.validate(new ValidationListener() {
    @Override
    public void onValidationSuccess(ValidatorInterface validatorInterface) {
        // on success code
    }

    @Override
    public void onValidationFailed(ValidatorInterface validatorInterface) {
        // show the errors if validation failed
        // we use the renderer class to handle the display
        ErrorRenderer errorRenderer = new ErrorRenderer(MainActivity.this,
                validatorInterface);
        errorRenderer.render(errorSpace);
    }
});