問題描述

當用戶輸入 EditText 時，我使用以下代碼執行搜索:

I use the following code to perform search when user types in an EditText :

EditText queryView = (EditText) findViewById(R.id.querybox);
queryView.addTextChangedListener(new TextWatcher() {
  @Override
  public void afterTextChanged(Editable s) {
    triggerSearch(s.toString()); 
  }
  @Override
  public void beforeTextChanged(CharSequence s, int start, int count, int after) {
  }
  @Override
  public void onTextChanged(CharSequence s, int start, int before, int count) {
  }
});

但是，當用戶鍵入一個單詞時，這會觸發多次.也就是說，如果用戶鍵入hello"，此代碼將觸發 5 次值(h"、he"、hel"、hell"、hello").通常，這會很好，但觸發搜索很昂貴，我不想將資源浪費在沒有多大用處的中間搜索上.我想要的是在用戶開始鍵入后僅觸發某個閾值的偵聽器，或者是某種框架，它在調用 triggerSearch 之前在偵聽器中等待，并且如果在該等待之前觸發了另一個事件, 自行取消.

However, this triggers multiple times when the user is typing a word. That is if the user is typing "hello", this code will trigger 5 times with values ("h", "he" , "hel", "hell", "hello"). Normally, this would be fine but the triggered search is expensive and I don't want to waste resources on intermediate searches that are of no great use. What I want is either a listener that triggers only a certain threshold after the user starts typing, or some kind of framework, that waits in the listener before calling triggerSearch, and if another event is triggered before that wait, cancels itself.

推薦答案

由于找不到合適的事件接口，嘗試觸發延遲搜索.代碼實際上非常簡單和健壯.

Since couldn't find an appropriate event interface, tried triggering a delayed search. The code is actually pretty simple and robust.

private final int TRIGGER_SERACH = 1;
// Where did 1000 come from? It's arbitrary, since I can't find average android typing speed.
private final long SEARCH_TRIGGER_DELAY_IN_MS = 1000;

  private Handler handler = new Handler() {
    @Override
    public void handleMessage(Message msg) {
      if (msg.what == TRIGGER_SERACH) {
        triggerSearch();
      }
    }
  };

 queryView.addTextChangedListener(new TextWatcher() {

   @Override
   public void beforeTextChanged(CharSequence charSequence, int i, int i2, int i3) {

   }

   @Override
   public void onTextChanged(CharSequence charSequence, int i, int i2, int i3) {

   }

   @Override
   public void afterTextChanged(Editable s) {
    handler.removeMessages(TRIGGER_SERACH);
    handler.sendEmptyMessageDelayed(TRIGGER_SERACH, SEARCH_TRIGGER_DELAY_IN_MS);
   });

這篇關于用戶打字時如何避免 EditText 上的多個觸發器?的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網！