Java 当输入字符串等于“时,ContextChanged方法中的NumberFormatException&引用;
我尝试创建一个警报对话框,其中只能输入数字,如果输入的数字小于5,则“确定”按钮将被禁用。当我输入某个内容并将其删除时,我会得到NumberFormatException:Java 当输入字符串等于“时,ContextChanged方法中的NumberFormatException&引用;,java,android,exception,android-alertdialog,numberformatexception,Java,Android,Exception,Android Alertdialog,Numberformatexception,我尝试创建一个警报对话框,其中只能输入数字,如果输入的数字小于5,则“确定”按钮将被禁用。当我输入某个内容并将其删除时,我会得到NumberFormatException: Process: com.example.emotionsanalyzer, PID: 9143 java.lang.NumberFormatException: For input string: "" at java.lang.Integer.parseInt(Integer.java:627)
Process: com.example.emotionsanalyzer, PID: 9143
java.lang.NumberFormatException: For input string: ""
at java.lang.Integer.parseInt(Integer.java:627)
at java.lang.Integer.parseInt(Integer.java:650)
at com.example.emotionsanalyzer.ui.CameraActivity$3.onTextChanged(CameraActivity.java:245)
以下是代码的一部分:
AlertDialog.Builder builder = new AlertDialog.Builder(this);
final EditText input = new EditText(this);
input.setInputType(InputType.TYPE_CLASS_NUMBER | InputType.TYPE_NUMBER_FLAG_DECIMAL);
builder.setView(input);
builder.setPositiveButton("OK", (dialog, which) -> {
intervalInMs = Integer.parseInt(input.getText().toString());
});
builder.setNegativeButton("Anuluj", (dialog, which) -> dialog.cancel());
AlertDialog dialog = builder.create();
input.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
dialog.getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(false);
}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
if (Integer.parseInt(s.toString()) >= 5){
dialog.getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(true);
}
else{
dialog.getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(false);
}
}
@Override
public void afterTextChanged(Editable s) {
}
});
dialog.show();
这是因为在onTextChanged()中,您执行了Integer.parseInt,并且刚刚删除或清除了该字段。它现在是空的,您正试图解析一个空字符串。 尝试在if条件中添加空字符串检查
if (s.isNotEmpty()) { // Add this line to check for empty string
if (Integer.parseInt....){
} else {
}
}
谢谢。确切地说,我把它改为if(!s.toString().isEmpty())