如何使用输入长度和范围设置 DocumentFilter?例如1-3 或 10-80
我正在使用 DocumentFilter 将输入限制为整数或小数.我在这里发布的代码对此非常有效.
I'm using DocumentFilter to restrict input as integer or decimal. And the code I post here is working well for that.
谁能帮助我了解如何限制给定代码中的输入长度或范围?
Can anybody help me about how to restrict the input length or range in the given code?
谢谢！！
class MyIntFilter extends DocumentFilter {
public void insertString(FilterBypass fb, int offset, String string,
AttributeSet attr) throws BadLocationException {
Document doc = fb.getDocument();
StringBuilder sb = new StringBuilder();
sb.append(doc.getText(0, doc.getLength()));
sb.insert(offset, string);
if (test(sb.toString())) {
super.insertString(fb, offset, string, attr);
} else {
// warn the user and don't allow the insert
}
}
private boolean test(String text) {
try {
Integer.parseInt(text);
return true;
} catch (NumberFormatException e) {
return false;
}
}
@Override
public void replace(FilterBypass fb, int offset, int length, String text,
AttributeSet attrs) throws BadLocationException {
Document doc = fb.getDocument();
StringBuilder sb = new StringBuilder(2);
sb.append(doc.getText(0, doc.getLength()));
sb.replace(offset, offset + length, text);
if (test(sb.toString())) {
super.replace(fb, offset, length, text, attrs);
} else {
// warn the user and don't allow the insert
}
}
@Override
public void remove(FilterBypass fb, int offset, int length)
throws BadLocationException {
Document doc = fb.getDocument();
StringBuilder sb = new StringBuilder(2);
sb.append(doc.getText(0, doc.getLength()));
//sb.append(doc.getText(0, 2));
sb.delete(offset, offset + length);
if (test(sb.toString())) {
super.remove(fb, offset, length);
} else {
// warn the user and don't allow the insert
}
}
}
推荐答案
你可能想测试一下(因为我没有)，但基本的想法应该让你开始.
You may want to test this (as I haven't), but the basic idea should get you started.
还可以查看 文档过滤器示例
至于设置最小长度，您可能需要使用 InputVerifier 以及
As to setting a minimum length, you may want to use a InputVerifier as well
class MyIntFilter extends DocumentFilter {
private int maxLength = 0;
public void setMaxLength(int maxLength) {
this.maxLength = maxLength;
}
public int getMaxLength() {
return maxLength;
}
public void insertString(FilterBypass fb, int offset, String string,
AttributeSet attr) throws BadLocationException {
Document doc = fb.getDocument();
StringBuilder sb = new StringBuilder();
sb.append(doc.getText(0, doc.getLength()));
sb.insert(offset, string);
if (maxLength > 0 && doc.getLength() + string.length() <= maxLength) {
if (test(sb.toString())) {
super.insertString(fb, offset, string, attr);
} else {
// warn the user and don't allow the insert
}
}
}
private boolean test(String text) {
try {
Integer.parseInt(text);
return true;
} catch (NumberFormatException e) {
return false;
}
}
@Override
public void replace(FilterBypass fb, int offset, int length, String text,
AttributeSet attrs) throws BadLocationException {
Document doc = fb.getDocument();
StringBuilder sb = new StringBuilder(2);
sb.append(doc.getText(0, doc.getLength()));
sb.replace(offset, offset + length, text);
if (test(sb.toString())) {
if (sb.length() > maxLength) {
length = sb.length() - maxLength;
if (length > 0) {
text = text.substring(0, length);
super.replace(fb, offset, length, text, attrs);
}
}
} else {
// warn the user and don't allow the insert
}
}
@Override
public void remove(FilterBypass fb, int offset, int length)
throws BadLocationException {
Document doc = fb.getDocument();
StringBuilder sb = new StringBuilder(2);
sb.append(doc.getText(0, doc.getLength()));
//sb.append(doc.getText(0, 2));
sb.delete(offset, offset + length);
if (test(sb.toString())) {
super.remove(fb, offset, length);
} else {
// warn the user and don't allow the insert
}
}
}
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