在需要做监听的js中添加
componentWillMount() {
if (Platform.OS === 'android') {
BackHandler.addEventListener('hardwareBackPress', this.onBackHandler);
}
}
componentWillUnmount() {
if (Platform.OS === 'android') {
BackHandler.removeEventListener('hardwareBackPress', this.onBackHandler);
}
}
onBackHandler = () => {
// this.onMainScreen and this.goBack are just examples, you need to use your own implementation here
// Typically you would use the navigator here to go to the last state.
if (!this.onMainScreen()) {
this.goBack();
return true;
}
return false;
};
RN的容器Activity实现DefaultHardwareBackBtnHandler接口
public class XXXActivity extends AppCompatActivity implements DefaultHardwareBackBtnHandler {
//...
private ReactInstanceManager mReactInstanceManager;
@Override
public void invokeDefaultOnBackPressed() {
if (mReactInstanceManager != null) {
mReactInstanceManager.onBackPressed();
} else {
super.onBackPressed();
}
}
//...
}
RN的容器为Fragment时，DefaultHardwareBackBtnHandler没起作用
这时我们需要在该Fragment中添加接收返回事件的代码
public boolean onKeyUp(int keyCode, KeyEvent event) {
if (mReactInstanceManager != null) {
switch (keyCode) {
//...
case KeyEvent.KEYCODE_BACK: {
mReactInstanceManager.onBackPressed();
return true;
}
}
}
return false;
}
并且在Activity中向该Fragment注入onkeyUp事件
@Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
return fragment.onKeyUp(keyCode, event) || super.onKeyUp(keyCode, event);
}
)
