com.facebook.react.bridge

Class BaseJavaModule

java.lang.Object

com.facebook.react.bridge.BaseJavaModule

All Implemented Interfaces:

NativeModule

Direct Known Subclasses:

AndroidInfoModule, ExceptionsManagerModule, ReactContextBaseJavaModule, SourceCodeModule

public abstract class BaseJavaModule
extends java.lang.Object
implements NativeModule

Base class for Catalyst native modules whose implementations are written in Java. Default implementations for initialize() and onCatalystInstanceDestroy() are provided for convenience. Subclasses which override these don't need to call super in case of overriding those methods as implementation of those methods is empty. BaseJavaModules can be linked to Fragments' lifecycle events, CatalystInstance creation and destruction, by being called on the appropriate method when a life cycle event occurs. Native methods can be exposed to JS with ReactMethod annotation. Those methods may only use limited number of types for their arguments: 1/ primitives (boolean, int, float, double 2/ String mapped from JS string 3/ ReadableArray mapped from JS Array 4/ ReadableMap mapped from JS Object 5/ Callback mapped from js function and can be used only as a last parameter or in the case when it express success & error callback pair as two last arguments respecively. All methods exposed as native to JS with ReactMethod annotation must return void. Please note that it is not allowed to have multiple methods annotated with ReactMethod with the same name.

Nested Class Summary

Nested classes/interfaces inherited from interface com.facebook.react.bridge.NativeModule

NativeModule.NativeMethod

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	METHOD_TYPE_REMOTE
static java.lang.String	METHOD_TYPE_REMOTE_ASYNC

Constructor Summary

Constructors

Constructor and Description
BaseJavaModule()

Method Summary

Methods

Modifier and Type	Method and Description
java.util.Map<java.lang.String,java.lang.Object>	getConstants()
java.util.Map<java.lang.String,NativeModule.NativeMethod>	getMethods()
void	initialize() This is called at the end of CatalystApplicationFragment#createCatalystInstance() after the CatalystInstance has been created, in order to initialize NativeModules that require the CatalystInstance or JS modules.
void	onCatalystInstanceDestroy() Called before {CatalystInstance#onHostDestroy}
void	writeConstantsField(com.fasterxml.jackson.core.JsonGenerator jg, java.lang.String fieldName) Append a field which represents the constants this module exports to JS.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.facebook.react.bridge.NativeModule

getName

Field Detail

METHOD_TYPE_REMOTE

public static final java.lang.String METHOD_TYPE_REMOTE

See Also:

Constant Field Values

METHOD_TYPE_REMOTE_ASYNC

public static final java.lang.String METHOD_TYPE_REMOTE_ASYNC

See Also:

Constant Field Values

Constructor Detail

BaseJavaModule

public BaseJavaModule()

Method Detail

getMethods

public final java.util.Map<java.lang.String,NativeModule.NativeMethod> getMethods()

Specified by:

getMethods in interface NativeModule

Returns:

methods callable from JS on this module

getConstants

@Nullable
public java.util.Map<java.lang.String,java.lang.Object> getConstants()

Returns:

a map of constants this module exports to JS. Supports JSON types.

writeConstantsField

public final void writeConstantsField(com.fasterxml.jackson.core.JsonGenerator jg,
                       java.lang.String fieldName)
                               throws java.io.IOException

Description copied from interface: NativeModule

Append a field which represents the constants this module exports to JS. If no constants are exported this should do nothing.

Specified by:

writeConstantsField in interface NativeModule

Throws:

java.io.IOException

initialize

public void initialize()

Description copied from interface: NativeModule

This is called at the end of CatalystApplicationFragment#createCatalystInstance() after the CatalystInstance has been created, in order to initialize NativeModules that require the CatalystInstance or JS modules.

Specified by:

initialize in interface NativeModule

onCatalystInstanceDestroy

public void onCatalystInstanceDestroy()

Description copied from interface: NativeModule

Called before {CatalystInstance#onHostDestroy}

Specified by:

onCatalystInstanceDestroy in interface NativeModule