EditText，当设置为maxLines = 1并且输入被按下时，它将被擦除并崩溃

Question

我有一个关于EditText的问题。做一个简单的数学游戏，玩家将得到这样的例子：9 x 9 = __。空格（= EditText，仅限于数字）是玩家必须从等式中填写正确答案的地方，然后按下[CORRECT] - 按钮来修正等式。

问题： 我目前设置了android.maxLines = "1"。现在每当玩家按下Enter键时，任何书面文字都将被删除。如果您重新输入并按下“正确”按钮，则应用程序停止工作。然而，只要你不按下输入应用程序工作得很好，使用正确的按钮。我如何防止它崩溃/停止工作？但是在按Enter键时也可以避免擦除任何数字。

XML文件：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:id="@+id/activity_play" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:paddingBottom="@dimen/activity_vertical_margin" 
    android:paddingLeft="@dimen/activity_horizontal_margin" 
    android:paddingRight="@dimen/activity_horizontal_margin" 
    android:paddingTop="@dimen/activity_vertical_margin" 
    tools:context="com.example.android.laboration2.EasyActivity"> 


    <TextView 
     android:id="@+id/textEasyMultiply" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignTop="@+id/textEasyNumber1" 
     android:layout_centerHorizontal="true" 
     android:layout_gravity="start" 
     android:text="@string/multiply" 
     android:textAlignment="textStart" 
     android:textColor="@android:color/black" 
     android:textSize="40sp" /> 

    <TextView 
     android:id="@+id/textEasyNumber1" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignParentTop="true" 
     android:layout_marginEnd="25dp" 
     android:layout_marginRight="25dp" 
     android:layout_marginTop="49dp" 
     android:layout_toLeftOf="@+id/answerButton" 
     android:layout_toStartOf="@+id/answerButton" 
     android:text="@string/number_1" 
     android:textAlignment="center" 
     android:textColor="@android:color/black" 
     android:textSize="50sp" /> 

    <TextView 
     android:id="@+id/textEasyEqual" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_below="@+id/textEasyNumber1" 
     android:layout_centerHorizontal="true" 
     android:layout_marginTop="18dp" 
     android:text="@string/equal" 
     android:textAlignment="center" 
     android:textColor="@android:color/black" 
     android:textSize="50sp" /> 

    <EditText 
     android:id="@+id/editTextEasyResult" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_below="@+id/textEasyEqual" 
     android:layout_centerHorizontal="true" 
     android:hint=" " 
     android:maxLines="1" 
     android:textAlignment="center" 
     android:textColor="@android:color/black" 
     android:textSize="50sp" /> 

    <TextView 
     android:id="@+id/textEasyScore" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignParentBottom="true" 
     android:layout_gravity="start" 
     android:layout_marginBottom="31dp" 
     android:layout_toLeftOf="@+id/answerButton" 
     android:layout_toStartOf="@+id/answerButton" 
     android:text="@string/score_0" 
     android:textAlignment="textStart" 
     android:textColor="@android:color/black" 
     android:textSize="24sp" /> 

    <Button 
     android:id="@+id/answerButton" 
     android:layout_width="120dp" 
     android:layout_height="wrap_content" 
     android:layout_below="@+id/editTextEasyResult" 
     android:layout_centerHorizontal="true" 
     android:layout_marginTop="36dp" 
     android:background="@android:color/holo_orange_dark" 
     android:text="@string/button_result" 
     android:textAllCaps="false" 
     android:textColor="@android:color/white" 
     android:textSize="18sp" 
     android:textStyle="bold" /> 

    <TextView 
     android:id="@+id/textEasyNumber2" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_above="@+id/textEasyEqual" 
     android:layout_alignEnd="@+id/textEasyLevel" 
     android:layout_alignRight="@+id/textEasyLevel" 
     android:layout_marginEnd="12dp" 
     android:layout_marginRight="12dp" 
     android:inputType="number" 
     android:text="@string/number_2" 
     android:textAlignment="center" 
     android:textColor="@android:color/black" 
     android:textSize="50sp" /> 

    <TextView 
     android:id="@+id/textEasyLevel" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignBaseline="@+id/textEasyScore" 
     android:layout_alignBottom="@+id/textEasyScore" 
     android:layout_toEndOf="@+id/answerButton" 
     android:layout_toRightOf="@+id/answerButton" 
     android:text="@string/level_0" 
     android:textAlignment="center" 
     android:textColor="@android:color/black" 
     android:textSize="24sp" /> 


</RelativeLayout> 

JAVA文件：

@Override 
public void onClick(View v) { 

    switch(v.getId()){ 
     case R.id.answerButton: 
      int easyNum1 = Integer.parseInt(textEasyNumber1.getText().toString()); 
      int easyNum2 = Integer.parseInt(textEasyNumber2.getText().toString()); 
      int easyResult = Integer.parseInt(editTextEasyResult.getText().toString()); 
      if(easyNum1 * easyNum2 == easyResult){ 
       currentScore++; 
       currentLevel++; 
       textEasyScore.setText("Score: " + currentScore); 
       textEasyLevel.setText("Level: " + currentLevel); 
       Toast.makeText(getApplicationContext(), "Good job!", Toast.LENGTH_LONG).show(); 
       editTextEasyResult.setText(""); 
      }else{ 
       currentScore = 0; 
       currentLevel = 0; 
       Toast.makeText(getApplicationContext(),"Wrong! :(", Toast.LENGTH_LONG).show(); 
      } 
      //Updates Scores & Level 
      textEasyScore.setText("Score: " + currentScore); 
      textEasyLevel.setText("Level: " + currentLevel); 
      break; 
    }//switch ends here 

    //stores the Score into the High Score page, when new High Score is reached it will auto-update 
    SharedPreferences sharedPrefsHighScore = getSharedPreferences("Prefs_HighScore",MODE_PRIVATE); 
    SharedPreferences.Editor editorScore = sharedPrefsHighScore.edit(); 
    int storedHighScore = sharedPrefsHighScore.getInt("highScore",0); 
    if (currentScore>storedHighScore) { 
     editorScore.putInt("highScore", currentScore); 
     editorScore.commit(); 

     //if a new High Score is achieved, the toastmessage "NEW HIGH SCORE!" will be shown (with modifications) 
     Toast highScoreToast = Toast.makeText(getApplicationContext(), "NEW HIGH SCORE!", Toast.LENGTH_LONG); 
      TextView toastMessage = (TextView) highScoreToast.getView().findViewById(android.R.id.message); 
      toastMessage.setTextColor(Color.WHITE); 
      toastMessage.setTextSize(25); 
     highScoreToast.show(); 
    }//if-statement ends here 

    randomNumbersForEquation(); 
}//onClick ends here 


//adds a random number for our Equation (for textEasyNumber1 and textEasyNumber2) 
void randomNumbersForEquation(){ 
    int addingOneTocurrentLevel = currentLevel + 1; 
    int numberRange = addingOneTocurrentLevel * 3; 
    Random randInt = new Random(); 

    int Number1 = randInt.nextInt(numberRange); 
    Number1++;//don't want a zero value 

    int Number2 = randInt.nextInt(numberRange); 
    Number2++;//don't want a zero value 

    textEasyNumber1.setText("" + Number1); 
    textEasyNumber2.setText("" + Number2); 
}//setQuestion ends here 

Answer 1

尝试这些在一起

  android:imeOptions="actionDone" 
      android:inputType="number" 
      android:maxLines="1" 

Answer 2

那么，当你按下 “ENTER” 键，文字不会被删除，而是向上移动。点击回车键后，按向上箭头键，你会发现你的文字。问题可能在于您为“正确”按钮编写的逻辑。请分享按“正确”按钮时执行的代码

已更新---尝试使用trim（）方法删除尾随空格。既然你解析值转换成int，则额外的空间可能是导致该问题的事情是这样的：

Integer.parseInt(editTextEasyResult.getText().toString().trim()); 

另一个建议是，因为你正在开发一个数学相关的应用程序，你可以限制你的EditText接受号只要。通过提以下属性为您编辑文本文件，这样做的：

android:inputType="number" 

这样做会出现数字键盘给用户无需输入密钥。