blocks|key|1326722|text|实现ItemStateListener接口。然后在表单构造函数中调用this.setItemStateListener(this)。实现itemStateChanged方法，以便如果项是您感兴趣的项，则获取其内容并测试其是否包含空格。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1326723|entityMap^0|2|H|Y|V|1W|G|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|O|8|@]|D|@]|E|$]]]|G|$]]

Implement the <code>ItemStateListener</code> interface. Then call <code>this.setItemStateListener(this)</code> in the Form constructor.
Implement the <code>itemStateChanged</code> method so that if the Item is the one you are interested in then get its content and test it if it contains spaces.

blocks|key|5013066|text|如果它是个人识别码，那么也许你应该用TextField.NUMERIC+%7C+TextField.PASSWORD替换constraints参数。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|5013067|entityMap^0|I|12|1M|B|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|M|8|@]|D|@]|E|$]]]|G|$]]

If it's a PIN number then maybe you should replace the <code>constraints</code> parameter with <code>TextField.NUMERIC | TextField.PASSWORD</code>.

blocks|key|5013117|text|在我的例子中，我创建了一个MIDlet和一个包含TextField的表单。而且它是有效的。我不知道你为什么说我给你的解决方案对你不起作用！下面是我给出的一个非常简单的例子(我创建并测试了它)：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5013118|package+hello;

import+javax.microedition.midlet.*;
import+javax.microedition.lcdui.*;

public+class+HelloMIDlet+extends+MIDlet+{

++++public+Display+display;

++++public+HelloMIDlet()+{
++++++++display+=+Display.getDisplay(this);
++++}

++++public+void+startApp()+{
++++++++Form+f+=+new+F(display);
++++++++display.setCurrent(f);
++++}

++++public+void+pauseApp()+{
++++}

++++public+void+destroyApp(boolean+unconditional)+{
++++}

}

package+hello;

import+javax.microedition.lcdui.Alert;
import+javax.microedition.lcdui.AlertType;
import+javax.microedition.lcdui.Display;
import+javax.microedition.lcdui.Form;
import+javax.microedition.lcdui.Item;
import+javax.microedition.lcdui.ItemStateListener;
import+javax.microedition.lcdui.TextField;

public+class+F+extends+Form+implements+ItemStateListener+{
++++private+TextField+pin+=+new+TextField("PIN+:","",4,TextField.PASSWORD);
++++private+Alert+alert;
++++private+Display+disp;
++++public+F(Display+d)
++++{
++++++++super("");
++++++++disp+=+d;
++++++++this.setItemStateListener(this);
++++++++this.append(pin);
++++}
++++public+void+itemStateChanged(Item+item)+{
++++++++if+(item+==+pin)
++++++++{
++++++++++++for+(int+i=0;+i<pin.getString().length();+i%2B%2B)
++++++++++++{
++++++++++++++++if+(String.valueOf(pin.getString().charAt(i)).equals(new+String("+")))
++++++++++++++++++++displayAlert();
++++++++++++}
++++++++}
++++}
++++private+void+displayAlert()
++++{
++++++++alert+=+new+Alert("Info","No+space+please+!",null,+AlertType.ERROR);
++++++++disp.setCurrent(alert,+this);
++++}
}|code-block|syntax|javascript|5013119|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

In my case I create a MIDlet and a Form which contains a TextField. And it works. I do not know why did you say that the solution I gave you did not work to you ! Here is a very simple example I give ( I created it and tested it ! ) :

<pre><code>package hello;

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

public class HelloMIDlet extends MIDlet {

 public Display display;

 public HelloMIDlet() {
 display = Display.getDisplay(this);
 }

 public void startApp() {
 Form f = new F(display);
 display.setCurrent(f);
 }

 public void pauseApp() {
 }

 public void destroyApp(boolean unconditional) {
 }

}

package hello;

import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.Item;
import javax.microedition.lcdui.ItemStateListener;
import javax.microedition.lcdui.TextField;

public class F extends Form implements ItemStateListener {
 private TextField pin = new TextField("PIN :","",4,TextField.PASSWORD);
 private Alert alert;
 private Display disp;
 public F(Display d)
 {
 super("");
 disp = d;
 this.setItemStateListener(this);
 this.append(pin);
 }
 public void itemStateChanged(Item item) {
 if (item == pin)
 {
 for (int i=0; i&lt;pin.getString().length(); i++)
 {
 if (String.valueOf(pin.getString().charAt(i)).equals(new String(" ")))
 displayAlert();
 }
 }
 }
 private void displayAlert()
 {
 alert = new Alert("Info","No space please !",null, AlertType.ERROR);
 disp.setCurrent(alert, this);
 }
}
</code></pre>

I have created a textfield that takes all characters from the user.. but i want to disable the space so that user cant enter space ...help??

<pre><code>pin = new TextField("Pin#","",4,TextField.PASSWORD);
</code></pre>

J2ME key event handling

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我已经创建了一个文本字段，它接受用户的所有字符。但是我想禁用空格，这样用户就不能输入空格...help?？pin = new TextField("Pin#","",4,TextField.PASSWORD);

问J2ME按键事件处理
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