当我在文本框中输入一些文本时，OnKey事件会发出两次。如何预防？ [英] OnKey event dispatched twice when I type some text into a textbox. How to prevent?

问题描述

在调试期间，我发现一件奇怪的事情发生了。我有一个 EditText 控件，我将当前活动定义为 OnKeyListener 以在用户类型时执行验证。

代码

  txtPhoneNumber.setOnEditorActionListener（this）; 
 txtPhoneNumber.setOnKeyListener（this）; 
 txtPhoneNumber.setOnFocusChangeListener（this）; 
 
 @Override 
 public boolean onEditorAction（TextView v，int actionId，KeyEvent event）{
 String phoneNumber =（（TextView）v）.getText（）。toString（）; 
 if（phoneNumber！= null&&！。equals（phoneNumber））
 setValidPhoneNumber（checkValidPhoneNumber（phoneNumber））; 
 
 setForwardButtonEnabled（this.validPhoneNumber&& this.readyToGo）; 
 
 if（actionId == EditorInfo.IME_ACTION_DONE）{
 InputMethodManager in =（InputMethodManager）getSystemService（Context.INPUT_METHOD_SERVICE）; 
 in.hideSoftInputFromWindow（v.getApplicationWindowToken（），InputMethodManager.HIDE_NOT_ALWAYS）; 
} 
 
 return false; 
 
 
 @Override 
 public boolean onKey（View v，int keyCode，KeyEvent event）{
 
 String phoneNumber =（（TextView）v） .getText（）的toString（）; 
 if（phoneNumber！= null&&！。equals（phoneNumber））
 setValidPhoneNumber（checkValidPhoneNumber（phoneNumber））; 
 
 setForwardButtonEnabled（this.validPhoneNumber&& this.readyToGo）; 
 
返回false; 
} 
  

确定我可以承认，当用户再次执行验证时，这是相当多余的正在按Enter键，而不仅仅是关闭软键盘。但是我发现OnKey事件是两次发布的。

例如我正在写 3551234567 ，我已经键入 355 。当我按1时，一个事件被触发，具有 v.getText（） = 355 ，另一个事件有 v.getText（） = 3551 。

我想知道这是否正常，如果这可以通过区分这是preOnKeyEvent还是postOnKeyEvent可以避免。 b

解决方案

您可能会收到钥匙扣/钥匙扣事件。

尝试过滤您的方法通过检查KeyEvent对ACTION_UP操作的操作。

阅读此获取更多信息

during my debug sessions I found a strange thing occurring. I have an EditText control for which I defined the current activity as OnKeyListener to perform validation while user types.

Code

txtPhoneNumber.setOnEditorActionListener(this);
txtPhoneNumber.setOnKeyListener(this);
txtPhoneNumber.setOnFocusChangeListener(this);

@Override
public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
    String phoneNumber = ((TextView) v).getText().toString();
    if (phoneNumber != null && !"".equals(phoneNumber))
        setValidPhoneNumber(checkValidPhoneNumber(phoneNumber));

    setForwardButtonEnabled(this.validPhoneNumber && this.readyToGo);

    if (actionId == EditorInfo.IME_ACTION_DONE) {
        InputMethodManager in = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
        in.hideSoftInputFromWindow(v.getApplicationWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS);
    }

    return false;
}

@Override
public boolean onKey(View v, int keyCode, KeyEvent event) {

    String phoneNumber = ((TextView) v).getText().toString();
    if (phoneNumber != null && !"".equals(phoneNumber))
        setValidPhoneNumber(checkValidPhoneNumber(phoneNumber));

    setForwardButtonEnabled(this.validPhoneNumber && this.readyToGo);

    return false;
}

OK I can admit that this is quite redundant to perform validation again when the user is pressing the Enter key, more than just closing the soft keyboard. However I found that the OnKey event is dispatched twice.

For example I'm writing 3551234567 and I already typed 355. When I press 1, one event is fired having v.getText() = 355 and next another event has v.getText() = 3551.

I would like to know if this is normal and if this can be avoided by either distinguishing if this is a "preOnKeyEvent" or "postOnKeyEvent". I only need the string after the event, not before.

Thank you

解决方案

You are probably getting both the key down/key up events.

Try filtering your method by checking the action of the KeyEvent for an ACTION_UP action.

Read this for more information

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