安卓:空指针异常对话框中 [英] Android: Null Pointer Exception in Dialog
问题描述
我在它显示有两个edittextboxes一个对话框。
I have a dialog box to be shown with two edittextboxes in it.
当我满山遍野并点击提交按钮,我需要保存在数据库中的值。我试图让在字段中输入的值,但空指针异常。
When I fill the fields and click on the submit button, I need to save the values in database. I am trying to get the values entered in the fields, but the Null Pointer Exception is raised.
我的code为如下
View v = getLayoutInflater().inflate(R.layout.sample, null);
new AlertDialog.Builder(Context)
.setTitle(R.string.Details)
.setView(v)
.setNegativeButton(R.string.Cancel,
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog,
int which) {
// TODO Auto-generated method stub
}
})
.setPositiveButton(R.string.Submit,
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog,
int which) {
final EditText txtname=(EditText)findViewById(R.id.editText1);
final EditText txtnumber=(EditText)findViewById(R.id.editText2);
Save(txtname.getText().toString(),txtnumber.getText().toString());
}
当我调试和检查,它显示为空txtName的和txtnumber值。为什么我在哪里出了错?我使用的是布局,以显示领域
when I debug and checked, It shows the txtname and txtnumber values as empty. Where did I went wrong? I was using a layout to show the fields
布局,
<?xml version="1.0" encoding="utf-8"?>
<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<TableRow>
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:text="Name" />
<EditText
android:id="@+id/editText1"
android:layout_width="195dp"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:ems="10"
android:hint="FirstName LastName"
android:inputType="textPersonName" />
</TableRow>
<TableRow>
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:text="Phone" />
<EditText
android:id="@+id/editText2"
android:layout_width="190dp"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:ems="10"
android:inputType="number"
android:maxLength="10" />
</TableRow>
请帮我解决这个例外!
推荐答案
您 txtName的
和 txtnumber
为空
即
final EditText txtname=(EditText)findViewById(R.id.editText1);
final EditText txtnumber=(EditText)findViewById(R.id.editText2);
当您试图访问空引用您将获得 NullPointerException异常
when you are trying to access null reference you will get NullPointerException
尽量让他们像这样
final EditText txtname=(EditText)v.findViewById(R.id.editText1);
final EditText txtnumber=(EditText)v.findViewById(R.id.editText2);
这篇关于安卓:空指针异常对话框中的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!