NullPointerException异常与字符串数组中微调 [英] NullPointerException with string-array in Spinner
问题描述
第一个应用程序,因此真正的新的安卓(打得四处大约一年前,但无疾而终),体面的编程。想以确保应用程序在手机上,没有功能的ATM呈现。编译好,有没有问题。它推到我的电话和不幸的是,Splitr已经停止。
编辑 - 添加到MainActivity.java,编辑操作之前和之后(而不是实际的code)*,但现在它的标志
adapter.setDropDownViewResource(android.R.layout.activity_main);
//应用适配器微调
spinnerSplit.setAdapter(适配器);
说错误:(18 36)标识符预期
setDropDownViewResource,activity_main和setAdapter所有红色
Android的工作室
摩托摹 - CM11 4.4.4
下面是code,让我知道,如果我错过了什么了。
MainActivity.java
包com.hydr0dr4gon.splitrv2;
进口android.app.Activity;
进口android.os.Bundle;
进口android.view.Menu;
进口android.view.MenuItem;
*进口android.widget.ArrayAdapter;
进口android.widget.Spinner; *
公共类MainActivity延伸活动{
*微调spinnerSplit =(微调)findViewById(R.id.spinner);
//创建一个使用字符串数组和默认微调布局ArrayAdapter
ArrayAdapter< CharSequence的>适配器= ArrayAdapter.createFromResource(这一点,
R.array.arraySplitr,android.R.layout.simple_spinner_item);
//指定被使用的布局出现选项列表时,
adapter.setDropDownViewResource(android.R.layout.activity_main);
//应用适配器微调
spinnerSplit.setAdapter(适配器); *
@覆盖
保护无效的onCreate(包savedInstanceState){
super.onCreate(savedInstanceState);
的setContentView(R.layout.activity_main);
}
@覆盖
公共布尔onCreateOptionsMenu(功能菜单){
//充气菜单;这增加了项目操作栏,如果它是present。
。getMenuInflater()膨胀(R.menu.main,菜单);
返回true;
}
@覆盖
公共布尔onOptionsItemSelected(菜单项项){
//处理动作栏项目点击这里。将操作栏
//自动在主/向上按钮操作的点击,只要
//你在AndroidManifest.xml中指定一个父活动。
INT的id = item.getItemId();
如果(ID == R.id.action_settings){
返回true;
}
返回super.onOptionsItemSelected(项目);
}
}
SplitrDialogFragment.java
包com.hydr0dr4gon.splitrv2;
进口android.app.AlertDialog;
进口android.app.Dialog;
进口android.app.DialogFragment;
进口android.content.DialogInterface;
进口android.os.Bundle;
公共类SplitrDialogFragment扩展DialogFragment {
@覆盖
公共对话onCreateDialog(包savedInstanceState){
//使用生成器类简单的对话框建设
AlertDialog.Builder建设者=新AlertDialog.Builder(getActivity());
builder.setMessage(R.string.dialog_split_pay)
.setNegativeButton(R.string.OK,新DialogInterface.OnClickListener(){
公共无效的onClick(DialogInterface对话框,INT ID){
//用户取消了对话框
}
});
//创建AlertDialog对象,并返回其
返回builder.create();
}
}
的strings.xml
< XML版本=1.0编码=UTF-8&GT?;
<资源>
<字符串名称=APP_NAME> Splitr< /串>
<字符串名称=参考hello world>世界,你好<!/串>
<字符串名称=action_settings>设置< /串>
<字符串名称=btnSplit>分割并LT; /串>
<字符串名称=btnTip> +提示< /串>
<字符串名称=txtSplit>斯普利特< /串>
<字符串名称=txtHint>输入比尔总计< /串>
<字符串名称=spinnerSplit>无。人与LT的; /串>
<字符串名称=dialog_split_pay>将个人自付LT; /串>
<字符串名称=OK>确定< /串>
<数组名=arraySplitr>
<项目> 2'; /项目>
<项目>第3版; /项目>
<项目> 4℃/项目>
<项目> 5℃/项目>
<项目> 6≤/项目>
<项目> 7< /项目>
<项目> 8示/项目>
<项目> 9< /项目>
<项目> 10< /项目>
< /阵列>
actvity_main.xml
RelativeLayout的的xmlns:机器人=http://schemas.android.com/apk/res/android
的xmlns:工具=http://schemas.android.com/tools
机器人:layout_width =FILL_PARENT
机器人:layout_height =FILL_PARENT
机器人:以下属性来=@扪/ activity_horizontal_margin
机器人:paddingRight =@扪/ activity_horizontal_margin
机器人:paddingTop =@扪/ activity_vertical_margin
机器人:paddingBottom会=@扪/ activity_vertical_margin
工具:上下文=com.hydr0dr4gon.splitr.MainActivity>
< TableLayout
机器人:layout_width =FILL_PARENT
机器人:layout_height =FILL_PARENT
机器人:layout_alignParentTop =真
机器人:layout_alignParentStart =真
机器人:以下属性来=40dp
机器人:paddingTop =80dp
机器人:paddingRight =40dp
机器人:paddingBottom会=80dp>
<的TableRow
机器人:layout_width =FILL_PARENT
机器人:layout_height =FILL_PARENT>
<的EditText
机器人:layout_width =WRAP_CONTENT
机器人:layout_height =WRAP_CONTENT
机器人:layout_span =2
机器人:inputType =数字
机器人:EMS =10
机器人:ID =@ + ID / EDITTEXT
机器人:layout_column =0
机器人:layout_weight =1.5
机器人:提示=@字符串/ txtHint/>
< /的TableRow>
<的TableRow
机器人:layout_width =FILL_PARENT
机器人:layout_height =FILL_PARENT>
<的TextView
机器人:layout_width =0dp
机器人:layout_height =match_parent
机器人:文本=@字符串/ txtSplit
机器人:ID =@ + ID / txtSplit
机器人:layout_weight =1
机器人:TEXTSIZE =32dp
机器人:textAlignment =中心
机器人:重力=中心/>
<微调
机器人:layout_width =0dp
机器人:layout_height =match_parent
机器人:ID =@ + ID /微调
机器人:layout_weight =1
机器人:spinnerStyle =@安卓风格/ Widget.Spinner.DropDown
机器人:textAlignment =中心
机器人:项=@阵列/ arraySplitr
机器人:提示=@字符串/ spinnerSplit/>
< /的TableRow>
<的TableRow
机器人:layout_width =FILL_PARENT
机器人:layout_height =FILL_PARENT>
<按钮
机器人:layout_width =0dp
机器人:layout_height =WRAP_CONTENT
机器人:文本=@字符串/ btnTip
机器人:ID =@ + ID / btnTip
机器人:layout_weight =1/>
<按钮
机器人:layout_width =0dp
机器人:layout_height =WRAP_CONTENT
机器人:文本=@字符串/ btnSplit
机器人:ID =@ + ID / btnSplit
机器人:layout_weight =1/>
< /的TableRow>
< / TableLayout>
logcat的
> 07-11 21:18:50.899 10290-10290 / com.hydr0dr4gon.splitrv2 D / ActivityThread:handleBindApplication:com.hydr0dr4gon.splitrv2
07-11 21:18:50.899 10290-10290 / com.hydr0dr4gon.splitrv2 D / ActivityThread:setTargetHeapUtilization:0.75
07-11 21:18:50.899 10290-10290 / com.hydr0dr4gon.splitrv2 D / ActivityThread:setTargetHeapMinFree:2097152
07-11 21:18:51.198 10290-10290 / com.hydr0dr4gon.splitrv2 D / AndroidRuntime:关闭虚拟机
07-11 21:18:51.206 10290-10290 / com.hydr0dr4gon.splitrv2 E / AndroidRuntime:致命异常:主要
工艺:com.hydr0dr4gon.splitrv2,PID:10290
显示java.lang.NullPointerException:尝试调用虚拟方法java.lang.String中java.lang.Object.toString()'对空对象引用
在android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:394)
在android.widget.ArrayAdapter.getView(ArrayAdapter.java:362)
在android.widget.AbsSpinner.onMeasure(AbsSpinner.java:193)
在android.widget.Spinner.onMeasure(Spinner.java:482)
在android.view.View.measure(View.java:16521)
在android.widget.TableRow.getColumnsWidths(TableRow.java:312)
在android.widget.TableLayout.findLargestCells(TableLayout.java:508)
在android.widget.TableLayout.measureVertical(TableLayout.java:473)
在android.widget.TableLayout.onMeasure(TableLayout.java:439)
在android.view.View.measure(View.java:16521)
在android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:719)
在android.widget.RelativeLayout.onMeasure(RelativeLayout.java:455)
在android.view.View.measure(View.java:16521)
在android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
在android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
在android.view.View.measure(View.java:16521)
在android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
在com.android.internal.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:327)
在android.view.View.measure(View.java:16521)
在android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
在android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
在com.android.internal.policy.impl.PhoneWindow $ DecorView.onMeasure(PhoneWindow.java:2552)
在android.view.View.measure(View.java:16521)
在android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1912)
在android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1109)
在android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1291)
在android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:996)
在android.view.ViewRootImpl $ TraversalRunnable.run(ViewRootImpl.java:5600)
在android.view.Choreographer $ CallbackRecord.run(Choreographer.java:761)
在android.view.Choreographer.doCallbacks(Choreographer.java:574)
在android.view.Choreographer.doFrame(Choreographer.java:544)
在android.view.Choreographer $ FrameDisplayEventReceiver.run(Choreographer.java:747)
在android.os.Handler.handleCallback(Handler.java:733)
在android.os.Handler.dispatchMessage(Handler.java:95)
在android.os.Looper.loop(Looper.java:136)
在android.app.ActivityThread.main(ActivityThread.java:5137)
在java.lang.reflect.Method.invoke(本机方法)
在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:795)
在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:611)
感谢。
显示java.lang.NullPointerException:尝试调用虚拟方法java.lang.String中java.lang.Object.toString ()'在一个空对象引用
在android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:394)
在android.widget.ArrayAdapter.getView(ArrayAdapter.java:362)
在android.widget.AbsSpinner.onMeasure(AbsSpinner.java:193)
在android.widget.Spinner.onMeasure(Spinner.java:482)
这告诉你错误是测量微调
。更确切地说,这应该里面显示的字符串之一为null。
最可能的原因是与的问题@阵列/ arraySplitr
资源。它是一个有效的字符串数组
资源的如文档中定义的?
本:
<数组名=arraySplitr>
<项目> 2'; /项目>
...
应该改为:
<字符串数组名=arraySplitr>
<项目> 2'; /项目>
...
在阵列
元素是的类型数组的。字符串数组必须使用字符串数组
。
First app and so really new at android (played around about a year ago but nothing came of it), decent at programming. Wanting to make sure app renders on a phone, no functionality atm. Compiles fine, no problems there. Push it to my phone and "Unfortunately, Splitr has stopped".
Edit - added to the MainActivity.java, edits have * before and after (not in actual code) but now it flags
adapter.setDropDownViewResource(android.R.layout.activity_main);
// Apply the adapter to the spinner
spinnerSplit.setAdapter(adapter);
saying Error:(18, 36) identifier expected
setDropDownViewResource, activity_main and setAdapter all in red
Android Studio
Moto G - CM11 4.4.4
Here is the code, let me know if I missed anything out.
MainActivity.java
package com.hydr0dr4gon.splitrv2;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
*import android.widget.ArrayAdapter;
import android.widget.Spinner;*
public class MainActivity extends Activity {
*Spinner spinnerSplit = (Spinner) findViewById(R.id.spinner);
// Create an ArrayAdapter using the string array and a default spinner layout
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this,
R.array.arraySplitr, android.R.layout.simple_spinner_item);
// Specify the layout to use when the list of choices appears
adapter.setDropDownViewResource(android.R.layout.activity_main);
// Apply the adapter to the spinner
spinnerSplit.setAdapter(adapter);*
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
SplitrDialogFragment.java
package com.hydr0dr4gon.splitrv2;
import android.app.AlertDialog;
import android.app.Dialog;
import android.app.DialogFragment;
import android.content.DialogInterface;
import android.os.Bundle;
public class SplitrDialogFragment extends DialogFragment {
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
// Use the Builder class for convenient dialog construction
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
builder.setMessage(R.string.dialog_split_pay)
.setNegativeButton(R.string.OK, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
// User cancelled the dialog
}
});
// Create the AlertDialog object and return it
return builder.create();
}
}
Strings.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">Splitr</string>
<string name="hello_world">Hello world!</string>
<string name="action_settings">Settings</string>
<string name="btnSplit">Split</string>
<string name="btnTip">+ Tip</string>
<string name="txtSplit">Split By</string>
<string name="txtHint">Enter Bill Total</string>
<string name="spinnerSplit">No. of People</string>
<string name="dialog_split_pay">Each Person Pays</string>
<string name="OK">OK</string>
<array name="arraySplitr">
<item>2</item>
<item>3</item>
<item>4</item>
<item>5</item>
<item>6</item>
<item>7</item>
<item>8</item>
<item>9</item>
<item>10</item>
</array>
actvity_main.xml
RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
tools:context="com.hydr0dr4gon.splitr.MainActivity">
<TableLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true"
android:paddingLeft="40dp"
android:paddingTop="80dp"
android:paddingRight="40dp"
android:paddingBottom="80dp">
<TableRow
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_span="2"
android:inputType="number"
android:ems="10"
android:id="@+id/editText"
android:layout_column="0"
android:layout_weight="1.5"
android:hint="@string/txtHint" />
</TableRow>
<TableRow
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView
android:layout_width="0dp"
android:layout_height="match_parent"
android:text="@string/txtSplit"
android:id="@+id/txtSplit"
android:layout_weight="1"
android:textSize="32dp"
android:textAlignment="center"
android:gravity="center" />
<Spinner
android:layout_width="0dp"
android:layout_height="match_parent"
android:id="@+id/spinner"
android:layout_weight="1"
android:spinnerStyle="@android:style/Widget.Spinner.DropDown"
android:textAlignment="center"
android:entries="@array/arraySplitr"
android:prompt="@string/spinnerSplit"/>
</TableRow>
<TableRow
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<Button
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="@string/btnTip"
android:id="@+id/btnTip"
android:layout_weight="1" />
<Button
android:layout_width="0dp"
android:layout_height="wrap_content"
android:text="@string/btnSplit"
android:id="@+id/btnSplit"
android:layout_weight="1" />
</TableRow>
</TableLayout>
logcat
> 07-11 21:18:50.899 10290-10290/com.hydr0dr4gon.splitrv2 D/ActivityThread﹕ handleBindApplication:com.hydr0dr4gon.splitrv2
07-11 21:18:50.899 10290-10290/com.hydr0dr4gon.splitrv2 D/ActivityThread﹕ setTargetHeapUtilization:0.75
07-11 21:18:50.899 10290-10290/com.hydr0dr4gon.splitrv2 D/ActivityThread﹕ setTargetHeapMinFree:2097152
07-11 21:18:51.198 10290-10290/com.hydr0dr4gon.splitrv2 D/AndroidRuntime﹕ Shutting down VM
07-11 21:18:51.206 10290-10290/com.hydr0dr4gon.splitrv2 E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.hydr0dr4gon.splitrv2, PID: 10290
java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference
at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:394)
at android.widget.ArrayAdapter.getView(ArrayAdapter.java:362)
at android.widget.AbsSpinner.onMeasure(AbsSpinner.java:193)
at android.widget.Spinner.onMeasure(Spinner.java:482)
at android.view.View.measure(View.java:16521)
at android.widget.TableRow.getColumnsWidths(TableRow.java:312)
at android.widget.TableLayout.findLargestCells(TableLayout.java:508)
at android.widget.TableLayout.measureVertical(TableLayout.java:473)
at android.widget.TableLayout.onMeasure(TableLayout.java:439)
at android.view.View.measure(View.java:16521)
at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:719)
at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:455)
at android.view.View.measure(View.java:16521)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
at android.view.View.measure(View.java:16521)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
at com.android.internal.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:327)
at android.view.View.measure(View.java:16521)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2552)
at android.view.View.measure(View.java:16521)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1912)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1109)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1291)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:996)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5600)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761)
at android.view.Choreographer.doCallbacks(Choreographer.java:574)
at android.view.Choreographer.doFrame(Choreographer.java:544)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5137)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:795)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:611)
Thanks.
java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String java.lang.Object.toString()' on a null object reference
at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:394)
at android.widget.ArrayAdapter.getView(ArrayAdapter.java:362)
at android.widget.AbsSpinner.onMeasure(AbsSpinner.java:193)
at android.widget.Spinner.onMeasure(Spinner.java:482)
This tells you that the error was measuring the Spinner
. More exactly, one of the strings that should be displayed inside it is null.
The most likely cause is a problem with the @array/arraySplitr
resource. Is it a valid string-array
resource as defined in the documentation?
This:
<array name="arraySplitr">
<item>2</item>
...
should be instead:
<string-array name="arraySplitr">
<item>2</item>
...
The array
element is for Typed Arrays. String arrays must use string-array
.
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