#  React Native Navigation v2 (WIP)
We are rebuilding react-native-navigation

- [Why?](#why-rebuild-react-native-navigation)
- [Where is it standing now?](#where-is-it-standing-now)
- [Getting Started](#getting-started-with-v2)
- [Usage](#usage)

## Why Rebuild react-native-navigation? 

### A New Improved Core Architecture
react-native-navigation has a few issues which are unsolvable in it’s current architecture. <br>
These issue originate from the same problem: you cannot specify on which screen you wish to make an action. Whenever you want to push, show modal or any other action, the action defaults to originate from your current screen. This covers most use cases but there are some edge cases: <br>
* What if you want to update your navbar icons and the user pops the screen? Your icons might update on the wrong screen.
* What if you want to push a screen as a result of a redux action? 

There are ways to solve some of these problems in v1 but they are not straightforward. We want to change that. 

#### New API
To solve this problem in v2, every screen receives as a prop it’s containerId. Whenever you want to perform an action from that screen you need to pass the containerId to the function: 
```js
Navigator.pop(this.props.containerId)
```   
### Built for Contributors 
Currently, it requires a lot of work to accept pull requests. We need to manually make sure that everything works before we approve them because v1 is not thoroughly tested. <br>
v2 is written with contributors in mind from day one.

#### Written In TDD
v2 is written in Test Driven Development. We have a test for every feature including features that are not implemented yet. This makes accepting pull requests extremely easy: If our tests pass, your pull request is accepted.


## Where is it standing now?
v2 currently supports most of react-native-navigation’s basic functions but it is still behind v1.
Here is the full comparison of features between v1 and v2 (will be updated regulary):
### Top Level API

|    API              | v1  | v2 |
|--------------------|-----|----|
| startTabBasedApp   |   ✅    |   ✅  |
| startSinglePageApp |   ✅   |  ✅   |
| registerScreen     |   ✅   |  ✅   |
| drawer             |    ✅  |    ✅ |
### Screen API

|  API              | v1     | v2         |
|---------------------|--------|------------|
| push                |  ✅     |   ✅       |
| pop                 |  ✅     |  ✅        |
| showModal           |  ✅     |  ✅ Only iOS [Contribute](CONTRIBUTING.md)   |
| popToRoot           |   ✅     |   ✅         |
| resetTo             |   ✅     |    [Contribute](CONTRIBUTING.md)      |
| dismissModal        |   ✅     |     ✅  Only iOS [Contribute](CONTRIBUTING.md)     |
| dismissAllModals    |   ✅     |      ✅   Only iOS  [Contribute](CONTRIBUTING.md)  |
| showLightBox        |   ✅     |      [Contribute](CONTRIBUTING.md)      |
| dismissLightBox     |   ✅     |       [Contribute](CONTRIBUTING.md)       |
| handleDeepLink      |   ✅     |       [Contribute](CONTRIBUTING.md)       |
| setOnNavigatorEvent |   ✅     |       [Contribute](CONTRIBUTING.md)       |
| setButtons          |   ✅     |         [Contribute](CONTRIBUTING.md)     |
| setTitle            |   ✅     |         [Contribute](CONTRIBUTING.md)     |
| toggleDrawer        |   ✅     |        [Contribute](CONTRIBUTING.md)   |
| toggleTabs          |   ✅     |        [Contribute](CONTRIBUTING.md)     |
| setTabBadge         |    ✅    |       [Contribute](CONTRIBUTING.md)     |
| switchToTab         |    ✅    |        [Contribute](CONTRIBUTING.md)    |
| toggleNavBar        |   ✅     |      [Contribute](CONTRIBUTING.md)      |
| Screen Visibility   |   ✅     |       ✅     |

Element tranisitions, adding buttons and styles are not yet implemented. [Contribute](CONTRIBUTING.md) 

## Getting started with v2
If v2 supports everything you need for your app we encourage you to use it.

### Installation 
1. Download react-native-navigation v2
```bash
yarn add react-native-navigation@alpha
```
##### iOS 
2. In Xcode, in Project Navigator (left pane), right-click on the `Libraries` > `Add files to [project name]`. Add `./node_modules/react-native-navigation/lib/ios/ReactNativeNavigation.xcodeproj` ([screenshots](https://facebook.github.io/react-native/docs/linking-libraries-ios.html#step-1))

3. In Xcode, in Project Navigator (left pane), click on your project (top) and select the `Build Phases` tab (right pane). In the `Link Binary With Libraries` section add `libReactNativeNavigation.a` ([screenshots](https://facebook.github.io/react-native/docs/linking-libraries-ios.html#step-2))

4. In Xcode, in Project Navigator (left pane), click on your project (top) and select the `Build Settings` tab (right pane). In the `Header Search Paths` section add `$(SRCROOT)/../node_modules/react-native-navigation/lib/ios`. Make sure on the right to mark this new path `recursive` ([screenshots](https://facebook.github.io/react-native/docs/linking-libraries-ios.html#step-3))

5. In Xcode, under your project files, modify `AppDelegate.m`. add:

`#import <ReactNativeNavigation/ReactNativeNavigation.h>`

remove everything in the method didFinishLaunchingWithOptions and add:

```
NSURL *jsCodeLocation = [[RCTBundleURLProvider sharedSettings] jsBundleURLForBundleRoot:@"index.ios" fallbackResource:nil];
[ReactNativeNavigation bootstrap:jsCodeLocation launchOptions:launchOptions];
```

##### Android
2. Add the following in `android/settings.gradle`.

	```groovy
	include ':react-native-navigation'
	project(':react-native-navigation').projectDir = new File(rootProject.projectDir, '../node_modules/react-native-	navigation/lib/android/app/')
	```

3. Update project dependencies in `android/app/build.gradle`.
	```groovy
	android {
		compileSdkVersion 25
		buildToolsVersion "25.0.1"
		...
	}

	dependencies {
		compile fileTree(dir: "libs", include: ["*.jar"])
		compile "com.android.support:appcompat-v7:23.0.1"
		compile "com.facebook.react:react-native:+"
		compile project(':react-native-navigation')
	}
	```

4. In `MainActivity.java` it should extend `com.reactnativenavigation.controllers.SplashActivity` instead of `ReactActivity`.

	This file can be located in `android/app/src/main/java/com/yourproject/`.

	```java
	import com.reactnativenavigation.controllers.SplashActivity;

	public class MainActivity extends SplashActivity {

	}
	```

	If you have any **react-native** related methods, you can safely delete them.

5. In `MainApplication.java`, add the following
	```java
	import com.reactnativenavigation.NavigationApplication;

	public class MainApplication extends NavigationApplication {

		@Override
		public boolean isDebug() {
			// Make sure you are using BuildConfig from your own application
			return BuildConfig.DEBUG;
		}

		protected List<ReactPackage> getPackages() {
			// Add additional packages you require here
			// No need to add RnnPackage and MainReactPackage
			return Arrays.<ReactPackage>asList(
				// eg. new VectorIconsPackage()
			);
		}

		@Override
		public List<ReactPackage> createAdditionalReactPackages() {
			return getPackages();
		}
	}
	```

	Make sure that `isDebug` and `createAdditionalReactPackages` methods are implemented.

6. Update `AndroidManifest.xml` and set **android:name** value to `.MainApplication`
	```xml
	<application
		android:name=".MainApplication"
		...
	/>
## Usage
### Top Screen API

#### Navigation
```js
import Navigation from 'react-native-navigation';
```
#### Events - On App Launched
How to initiate your app.

```js
Navigation.events().onAppLaunched(() => {
    Navigation.setRoot({
      container: {
        name: 'navigation.playground.WelcomeScreen'
      }
    });
  });
```

#### registerContainer(screenID, generator)
Every screen component in your app must be registered with a unique name. The component itself is a traditional React component extending React.Component.
```js
Navigation.registerContainer(`navigation.playground.WelcomeScreen`, () => WelcomeScreen);
```

#### setRoot({params})
Start a Single page app with two side menus: 
```js
Navigation.setRoot({
      container: {
        name: 'navigation.playground.WelcomeScreen'
      },
      sideMenu: {
        left: {
          container: {
            name: 'navigation.playground.TextScreen',
            passProps: {
              text: 'This is a left side menu screen'
            }
          }
        },
        right: {
          container: {
            name: 'navigation.playground.TextScreen',
            passProps: {
              text: 'This is a right side menu screen'
            }
          }
        }
      }
    });
```
Start a tab based app: 
```js
Navigation.setRoot({
      tabs: [
        {
          container: {
            name: 'navigation.playground.TextScreen',
            passProps: {
              text: 'This is tab 1',
              myFunction: () => 'Hello from a function!'
            }
          }
        },
        {
          container: {
            name: 'navigation.playground.TextScreen',
            passProps: {
              text: 'This is tab 2'
            }
          }
        }
      ]
    });
```
### Screen API

#### push(params)
Push a new screen into this screen's navigation stack.
```js
Navigation.push(this.props.containerId, {
      name: 'navigation.playground.PushedScreen',
      passProps: {}
    });
```
#### pop(containerId)
Pop the top screen from this screen's navigation stack.
```js
Navigation.pop(this.props.containerId);
```
#### popTo(params)
```js
Navigation.popTo(this.props.containerId, this.props.previousScreenIds[0]);
```
#### popToRoot()
Pop all the screens until the root from this screen's navigation stack
```js
Navigation.popToRoot(this.props.containerId);
```
#### showModal(params = {})
Show a screen as a modal.
```js
Navigation.showModal({
      container: {
        name: 'navigation.playground.ModalScreen',
        passProps: {
            key: 'value'
        }
      }
    });
```
#### dismissModal(containerId)
Dismiss modal.
```js
Navigation.dismissModal(this.props.containerId);
```
#### dismissAllModals()
Dismiss all the current modals at the same time.
```js
Navigation.dismissAllModals();
```
#### Screen Lifecycle - onStop() and onStart()

the onStop() and onStart() function are lifecycle functions that are added to the screen and run when a screen apears and disappears from the screen. to use them simply add them to your component like any other react lifecycle function: 

```js
class LifecycleScreen extends Component {
  constructor(props) {
    super(props);
    this.state = {
      text: 'nothing yet'
    };
  }

  onStart() {
    this.setState({ text: 'onStart' });
  }

  onStop() {
    alert('onStop'); //eslint-disable-line
  }

  componentWillUnmount() {
    alert('componentWillUnmount'); //eslint-disable-line
  }

  render() {
    return (
      <View style={styles.root}>
        <Text style={styles.h1}>{`Lifecycle Screen`}</Text>
	<Text style={styles.h1}>{this.state.text}</Text>
      </View>
    );
  }
}
```