java Android EditView输入限制（软键盘限制）

Posted 2021-05-08

传入正则规则即可，灵活性比较高。

public static final String LIMIT_PHONE_INPUT = "^1\\d{0,10}$";//限制只允许输入首位为1的最多11位的数字
EditView etInputFilter = (EditView)findViewById(R.id.etInputFilter);
etInputFilter.setFilters(new EditInputFilter(LIMIT_PHONE_INPUT));
/**
 * Created by xugang on 2016/6/22.
 * EditView过滤器
 */
public class EditInputFilter implements InputFilter {
    //
    private String regular;
    public EditInputFilter(String regular) {
        this.regular = regular;
    }
    @Override
    public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {
        if (regular == null)
            return source;
        if (dstart == 0 && dend == 0 && TextUtils.isEmpty(source))
            return null;
        if (dstart == dend) {
            //输入
            StringBuilder builder = new StringBuilder(dest);
            if (builder.append(source).toString().matches(regular)) return source;
            else return "";
        }
        return source;
    }
}

此方式也比较灵活，不错的方式。

EditText etTextWatcher = (EditText) findViewById(R.id.etTextWatcher);
etTextWatcher.addTextChangedListener(new EditTextWatcher(etTextWatcher));
/**
 * Created by xugang on 2016/6/23.
 * 输入监听
 */
public class EditTextWatcher implements TextWatcher {
    private EditText editText;
    public EditTextWatcher(EditText editText) {
        this.editText = editText;
    }
    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
    }
    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        if (s != null && s.length() > start) {
            //输入判断规则
            if (!RegularUtils.compare(s.toString().trim(), RegularUtils.LIMIT_PHONE_INPUT)) {
                editText.setText(s.subSequence(0, s.length() - 1));
                editText.setSelection(s.length() - 1);
            }
        }
    }
    @Override
    public void afterTextChanged(Editable s) {
    }
}

如下设置为：只能输入0-5之间的数字，且最多11位。

 <EditText
        android:id="@+id/etDigits"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:digits="012345"
        android:hint="通过digits设置"
        android:inputType="number"
        android:maxLength="11" />



PS:优点：简单方便； 
缺点：只能设置简单的限制，如果需要设置的比较复杂，如数字字母和某些特定字符则需要在digits中穷举出来。