addHandler method
添加脚本注册方法
Implementation
void addHandler(String methodName, JavascriptMessageHandler onMessageReceived) {
if (methodName.isEmpty) {
return;
}
JavascriptChannel channel = new JavascriptChannel(
name: methodName,
onMessageReceived: (JavascriptMessage message) {
var callReceive = _JavascriptCallReceive(methodName, message, onMessageReceived);
callReceive.call();
});
if (jsChannels.containsKey(methodName)) {
jsChannels[methodName] = channel;
} else {
jsChannels.putIfAbsent(methodName, () => channel);
}
}