/** Called when the user clicks the Send button */
public void sendMessage(View view) {
Intent intent = new Intent(this, DisplayMessageActivity.class);
EditText editText = (EditText) findViewById(R.id.edit_message);
String message = editText.getText().toString();
intent.putExtra(EXTRA_MESSAGE, message);
startActivity(intent);
}
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在线
EditText editText = (EditText) findViewById(R.id.edit_message);
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EditText是类,
editText是我们正在创建的实例.
findViewById(R.id.edit_message)是方法,R.id.edit_message是我们传递的论据
但我不明白为什么会有(EditText)礼物?它是对构造函数的调用吗?
如何在textview示例(.set.)的垂直中心设置点,我想要两个点在设置文本的垂直中心.我已经尝试过重力中心,但没有取得任何成功,你可以参考附加图像,刚刚显示的点显示非常浅的颜色,我想要相同,所以请建议如何实现这一点

我有一个ListView内心ScrollView.我可以启用滚动ListView通过
listView.getParent().requestDisallowInterCeptTouchEvent(true);
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但问题是当我在listView中向上滚动并且它到达顶部时它应该滚动到父视图,即父滚动必须工作.我怎样才能做到这一点 ?任何建议请.
看过Double.java的源代码和一些常量就好
/**
* Constant for the Not-a-Number (NaN) value of the {@code double} type.
*/
public static final double NaN = 0.0 / 0.0;
/**
* Constant for the positive infinity value of the {@code double} type.
*/
public static final double POSITIVE_INFINITY = 1.0 / 0.0;
/**
* Constant for the negative infinity value of the {@code double} type.
*/
public static final double NEGATIVE_INFINITY = -1.0 / 0.0;
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但我想知道它为什么不抛出ArithmeticException(除以零)?
我试过了
public static final int VALUE = 0/0;
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现在它正在抛出异常,但是当我说 …
我正在开发一个应用程序,我必须将数据发送到服务器.我得到异常,同时获取用户详细信息nullpointer异常请告诉我我在哪里犯了错误
myActivity代码
userDetails = new DetailsDTO();
userName = userNameEdit.getText().toString().trim();
password = passwordEdit.getText().toString().trim();
confirmPwd = confirmPasswordEdit.getText().toString();
mobileNo = mobileNoEdit.getText().toString();
userDetails.setUserName(userName);
userDetails.setPassword(password);
userDetails.setConfirmPwd(confirmPwd);
userDetails.setMobileNumber(mobileNo);
(new UserDetailsAsync(mContext)).execute();
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我的AsyncTask代码:
@Override
protected Void doInBackground(Void... params) {
// TODO Auto-generated method stub
httpClient = new DefaultHttpClient();
httpPost = new HttpPost(TrafficConstants.USER_REG_URL);
Log.e("userName", details.getUserName());
Log.e("pass", details.getPassword());
Log.e("MOb",details.getMobileNumber());
try{
arrayList = new ArrayList<NameValuePair>(3);
arrayList.add(new
BasicNameValuePair("usr",details.getUserName()));
arrayList.add(new
BasicNameValuePair("pass",details.getPassword()));
arrayList.add(new
BasicNameValuePair("mob",details.getMobileNumber()));
httpPost.setEntity(new UrlEncodedFormEntity(arrayList));
HttpResponse response = httpClient.execute(httpPost);
}
catch(Exception e){
e.printStackTrace();
}
return null;
}
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LogCat错误
02-20 12:16:37.535: E/AndroidRuntime(2605): java.lang.RuntimeException: An …Run Code Online (Sandbox Code Playgroud) event.getX()和event.getRawX().之间的主要区别是什么 .使用哪种情况.event.getRawX()可以解释一下细节吗?