Java logcat中没有我的代码的Null指针异常
我得到了一个NPE,但是当我检查logcat时,它没有使用我的代码 试图显示包含RadioButtonGroup的AlertDialog后,程序崩溃。它以前工作过,我记得唯一的变化是在对话框之后 现在,我收到以下消息: 编辑:Java logcat中没有我的代码的Null指针异常,java,android,nullpointerexception,Java,Android,Nullpointerexception,我得到了一个NPE,但是当我检查logcat时,它没有使用我的代码 试图显示包含RadioButtonGroup的AlertDialog后,程序崩溃。它以前工作过,我记得唯一的变化是在对话框之后 现在,我收到以下消息: 编辑: 06-19 17:15:19.430: E/AndroidRuntime(898): java.lang.NullPointerException 06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.
06-19 17:15:19.430: E/AndroidRuntime(898): java.lang.NullPointerException
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:394)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.ArrayAdapter.getView(ArrayAdapter.java:362)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.AbsListView.obtainView(AbsListView.java:2143)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.ListView.measureHeightOfChildren(ListView.java:1246)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.ListView.onMeasure(ListView.java:1158)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.View.measure(View.java:15518)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4825)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.View.measure(View.java:15518)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4825)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.View.measure(View.java:15518)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4825)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.View.measure(View.java:15518)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4825)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.View.measure(View.java:15518)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4825)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
06-19 17:15:19.430: E/AndroidRuntime(898): at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2176)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.View.measure(View.java:15518)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1874)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1089)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1265)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:989)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4351)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:749)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.Choreographer.doCallbacks(Choreographer.java:562)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.Choreographer.doFrame(Choreographer.java:532)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:735)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.os.Handler.handleCallback(Handler.java:725)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.os.Handler.dispatchMessage(Handler.java:92)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.os.Looper.loop(Looper.java:137)
06-19 17:15:19.430: E/AndroidRuntime(898): at android.app.ActivityThread.main(ActivityThread.java:5041)
06-19 17:15:19.430: E/AndroidRuntime(898): at java.lang.reflect.Method.invokeNative(Native Method)
06-19 17:15:19.430: E/AndroidRuntime(898): at java.lang.reflect.Method.invoke(Method.java:511)
06-19 17:15:19.430: E/AndroidRuntime(898): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
06-19 17:15:19.430: E/AndroidRuntime(898): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
06-19 17:15:19.430: E/AndroidRuntime(898): at dalvik.system.NativeStart.main(Native Method)
当我单步执行时,运行的最后一个代码块是:
public void addTeam (View view) {
//open select race dialog
AlertDialog alertDialog;
AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
String[] items = new String[races.size()];
int i = 0;
for (Race race : races) {
//add radio button for each race
items[i] = race.raceName;
}
builder.setTitle(getString(R.string.select_race));
builder.setSingleChoiceItems(items, 0, null);
builder.setPositiveButton(R.string.done, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialogInterface, int whichButton) {
dialogInterface.dismiss();
Team team = new Team();
team.raceIndex = ((AlertDialog) dialogInterface).getListView().getCheckedItemPosition();
team.raceName = races.get(team.raceIndex).raceName;
setContentView(R.layout.edit_team);
((TextView) findViewById(R.id.raceTV)).setText(team.raceName);
}
});
alertDialog = builder.create();
alertDialog.show();
}
如果没有代码的行引用,我甚至不知道从哪里开始。非常感谢您的帮助。您有两个
对话框
实例。1) AlertDialog代码>和2)对话框界面对话框
。所以很可能是AlertDialog代码>抛出NPE
,因为它从未初始化过,所以定义为null
您有两个对话框
实例。1) AlertDialog代码>和2)对话框界面对话框
。所以很可能是AlertDialog代码>抛出NPE
,因为它从未初始化过,所以建议将其替换为null
((TextView) findViewById(R.id.raceTV)).setText(team.raceName);
与
替换这个
((TextView) findViewById(R.id.raceTV)).setText(team.raceName);
与
您的代码中有一个错误:
int i = 0;
for (Race race : races) {
//add radio button for each race
items[i] = race.raceName;
}
在for循环中不增加i
。
这可能是导致崩溃的原因。您的代码中有一个错误:
int i = 0;
for (Race race : races) {
//add radio button for each race
items[i] = race.raceName;
}
在for循环中不增加i
。
可能是这导致了撞车。是的。对代码的引用将进一步深入堆栈跟踪<代码>对话框
确实为空。这是完整的堆栈跟踪。两个对话框都不是空的,但为了清晰起见编辑了变量名。是的。对代码的引用将进一步深入堆栈跟踪<代码>对话框
确实为空。这是完整的堆栈跟踪。两个对话框都不是空的,但为了清晰起见编辑了变量名。你确定吗?如果数组的长度大于1,则只有第一个条目不为null,并且我认为适配器在尝试访问第二个元素Thanx时崩溃,我猜,因为它以前工作过。我一定是删除了I++。对不起,我错了!我没有看到这个数组在生成器中使用。你确定吗?如果数组的长度大于1,则只有第一个条目不为null,并且我认为适配器在尝试访问第二个元素Thanx时崩溃,我猜,因为它以前工作过。我一定是删除了I++。对不起,我错了!我没有看到这个数组在生成器中使用。这个故事的寓意。如果你的代码不在堆栈跟踪中,你可能发出了一个不正确的变量。故事的寓意。如果代码不在堆栈跟踪中,则可能发送了不正确的变量。