场景：
用户输入搜索内容，进行输入框的变化监听，提供联想词。
需求：
避免频繁请求，限制时间内获取用户最后想搜索的内容
方案1：Handler实现
利用postDelayed方法和可撤销的removeCallbacks方法实现
private Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
if (EDIT_OK == msg.what) {
String newText = etSearch.getText().toString();
if(!TextUtils.isEmpty(newText)) {
setInputtipsQuery(newText);
}
}
}
};
private Runnable mRunnable = new Runnable() {
@Override
public void run() {
mHandler.sendEmptyMessage(EDIT_OK);
}
};
etSearch.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
}
@Override
public void afterTextChanged(Editable s) {
mHandler.removeCallbacks(mRunnable);
//600毫秒没有输入认为输入完毕
mHandler.postDelayed(mRunnable, 600);
}
});
方案2：RxJava操作符进行限流
操作函数：debounce，500毫秒内采取最后一次的操作
subject.debounce(500, TimeUnit.MILLISECONDS).observeOn(AndroidSchedulers.mainThread())
.subscribe(new Subscriber<CharSequence>() {
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable arg0) {
}
@Override
public void onNext(CharSequence charSequence) {
Log.d(TAG, "onNext" + charSequence.toString());
showSearchResult(charSequence);
}
});