Kubwa
An Annotation based validation library for use with Android's DataBinding library in an MVVM architecture.
- Quick and easily add validation rules to ViewModels by annotating the class
- Annotation Processing to elimate reflection and generate boilerplate validation classes
Usage
- Simply annotate your ViewModel class with the validation rules need:
@Email(errorMessage = R.string.email_error) @Password(errorMessage = R.string.password_error, scheme = PasswordRule.Scheme.ALPHA_NUMERIC_SYMBOLS) public class LoginViewModel extends BaseObservable {
LoginViewModelValidator validator; // Generated when project is built
public LoginViewModel(Context contex) {
validator = new LoginViewModelValidator(context);
// Instantiate the validator with a Context
}
}
Note: Each validation rule ( @Email, @Password, etc) requires an errorMessage String resource parameter
For a list of annotation rules, check out the Annotations
- Make sure your layout and ViewModel are setup for DataBinding Layout.xml:
<layout>
<data>
<variable name="viewModel" type="com.wesleyelliott.kubwa.LoginViewModel" />
</data>
<LinearLayout>
<EditText
...
android:text="@={
viewModel.email
}
"
app:error="@{
viewModel.emailError
}
"/>
<EditText
...
android:text="@={
viewModel.password
}
"
app:error="@{
viewModel.passwordError
}
"/>ViewModel:
public String getEmailError() {
return validator.getEmailErrorMessage();
}
public String getPasswordError() {
return validator.getPasswordErrorMessage();
}
- Validate each rule independantly, or all together (in the same order as the annotations):
private void login() {
// Either
validator.validateEmail(getEmail());
validator.validatePassword(getPassword());
// Or
validator.validateAll(getEmail(), getPassword());
notifyChange();
if (validator.isValid()) {
// Todo: Log user in
}
}
And thats it! notifyChange() will ensure the errors (if any) are shown on the correct EditText's
Download
Your project level gradle config ( build.gradle) needs to have the android-apt plugin setup, as well as the jcenter repository:
buildscript {
repositories {
mavenCentral()
jcenter()
}
dependencies {
classpath 'com.neenbedankt.gradle.plugins:android-apt:1.8'
}
}
Apply the android-apt plugin to your module's build file, add the kubwa-compiler and kubwa-annotations dependancies and make sure Android DataBinding is setup:
apply plugin: 'android-apt' android {
...
dataBinding {
enabled = true
}
}
dependencies {
compile 'com.wesleyelliott:kubwa-annotations:1.0.1'
apt 'com.wesleyelliott:kubwa-compiler:1.0.1'
}
License
Copyright 2016 Wesley Elliott Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.