我正在开发一个android，它包含一个由空白数据库表填充的列表视图，第一个选项为“新建”。当用户单击“新建”时，将加载用户填写的表单，并在单击表单中的“保存”时将其存储在列表视图的数据库表中。再次当用户打开此列表视图时，它将具有“新建”以及用户填写的表单作为选项说明 创建新表单和表单1.表单中很少有微调器由数据库中的另一个表填充
到此为止一切都很好。当用户单击Form1时，它会加载他已填写的表单进行编辑。
我面临的问题是每当用户加载表单并旋转手机时，它就会被强制关闭。同样的事情也发生在列表视图中。每当我进入listview并旋转手机时，它就会被强制关闭。
这是我的logcat
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): FATAL EXCEPTION: main
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): java.lang.NullPointerException
08-15 09:39:36.759: ERROR/AndroidRuntime(6481):at com.sufoin.mormeds.Submit$2.onItemSelected(Submit.java:366)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.AdapterView.fireOnSelected(AdapterView.java:871)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.AdapterView.selectionChanged(AdapterView.java:854)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.AdapterView.checkSelectionChanged(AdapterView.java:977)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.AdapterView.handleDataChanged(AdapterView.java:959)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.AbsSpinner.onMeasure(AbsSpinner.java:179)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.View.measure(View.java:8330)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.TableRow.measureChildBeforeLayout(TableRow.java:221)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:701)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.TableRow.onMeasure(TableRow.java:112)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.View.measure(View.java:8330)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.TableLayout.measureChildBeforeLayout(TableLayout.java:456)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.LinearLayout.measureVertical(LinearLayout.java:386)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.TableLayout.measureVertical(TableLayout.java:468)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.TableLayout.onMeasure(TableLayout.java:431)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.View.measure(View.java:8330)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:701)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.LinearLayout.onMeasure(LinearLayout.java:311)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.View.measure(View.java:8330)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.ScrollView.measureChildWithMargins(ScrollView.java:1082)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.FrameLayout.onMeasure(FrameLayout.java:250)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.ScrollView.onMeasure(ScrollView.java:296)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.View.measure(View.java:8330)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.LinearLayout.measureVertical(LinearLayout.java:386)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.LinearLayout.onMeasure(LinearLayout.java:309)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.View.measure(View.java:8330)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.FrameLayout.onMeasure(FrameLayout.java:250)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.View.measure(View.java:8330)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.LinearLayout.measureVertical(LinearLayout.java:531)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.LinearLayout.onMeasure(LinearLayout.java:309)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.View.measure(View.java:8330)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.widget.FrameLayout.onMeasure(FrameLayout.java:250)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.View.measure(View.java:8330)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.ViewRoot.performTraversals(ViewRoot.java:839)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.view.ViewRoot.handleMessage(ViewRoot.java:1860)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.os.Handler.dispatchMessage(Handler.java:99)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.os.Looper.loop(Looper.java:123)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at android.app.ActivityThread.main(ActivityThread.java:3835)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at java.lang.reflect.Method.invokeNative(Native Method)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at java.lang.reflect.Method.invoke(Method.java:507)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:841)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:599)
08-15 09:39:36.759: ERROR/AndroidRuntime(6481): at dalvik.system.NativeStart.main(Native Method)
这是发生错误的代码。它用于初始化和设置微调器
private void initandsetspinners(final Spinner gen, final Spinner prinum, final Spinner alternum, final Spinner precon, final Spinner dep, final Spinner pra, final Spinner add) {
//Initializing the shared preferences variable
final SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getBaseContext());
//Creating an object called mydbhelper
Dbms mydbhelper = new Dbms(this);
//Loading the database in writable format
final SQLiteDatabase db=mydbhelper.getWritableDatabase();
//For Medicines Table
try{
//For medicines
Cursor medspin = db.query("medicines", null,null,null,null,null,null);
medspin.moveToPosition(prefs.getInt("pos",1));
//Filling the variables to set selemedspintion
deptpos=medspin.getInt(medspin.getColumnIndex("provider_department"));
practipos=medspin.getInt(medspin.getColumnIndex("provider_practice"));
addrpos=medspin.getInt(medspin.getColumnIndex("provider_address"));
hsname=medspin.getString(medspin.getColumnIndex("healthsystem"));
medspin.close();
//For user_masterdata table
Cursor userspin = db.query("user_masterdata", null,null,null,null,null,null);
userspin.moveToPosition(0);
//Filling the variables to set seleuserspintion
genpos=userspin.getInt(userspin.getColumnIndex("gender"));
pripos=userspin.getInt(userspin.getColumnIndex("primarynumbertype"));
altpos=userspin.getInt(userspin.getColumnIndex("alternatenumbertype"));
prefpos=userspin.getInt(userspin.getColumnIndex("prefcontactype"));
userspin.close();
}
catch(Exception e){
Log.e("Error","Error",e);
}
//Initializing the spinners
//Gender
ArrayAdapter<CharSequence> gentype = ArrayAdapter.createFromResource(this,R.array.gender, android.R.layout.simple_spinner_item);
gentype.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
gen.setAdapter(gentype);
//Primary Number
ArrayAdapter<CharSequence> prinumtype = ArrayAdapter.createFromResource(this,R.array.pnumtype, android.R.layout.simple_spinner_item);
prinumtype.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
prinum.setAdapter(prinumtype);
//Alternate Number
ArrayAdapter<CharSequence> altnumtype = ArrayAdapter.createFromResource(this,R.array.anumtype, android.R.layout.simple_spinner_item);
altnumtype.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
alternum.setAdapter(altnumtype);
//Preferred Contact type
ArrayAdapter<CharSequence> preftype = ArrayAdapter.createFromResource(this,R.array.precontype, android.R.layout.simple_spinner_item);
preftype.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
precon.setAdapter(preftype);
try{
//Cursor
Cursor depcur = db.rawQuery("SELECT _id,department,"+prefs.getString("hsname",null)+ " FROM dept_masterdata WHERE "+prefs.getString("hsname",null)+"=1",null);
depcur.moveToFirst();
startManagingCursor(depcur);
String[] from = new String[]{"department"};
int[] to = new int[] { android.R.id.text1 };
// Now creating an array adapter and set it to display using my row
//Adaptor for Department
SimpleCursorAdapter deptype =new SimpleCursorAdapter(this,android.R.layout.simple_spinner_item, depcur, from, to);
deptype.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
dep.setAdapter(deptype);
}
catch(Exception e){
Log.e("Error","Error",e);
}
//Now determine which department is selected
//Department
dep.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent,View view,int pos,long id){
deptid=dep.getSelectedItemId();
//Setting the practice spinner based on the department selected
Cursor pracur = db.rawQuery("SELECT _id,practice,dept_link,hs_id FROM practice_masterdata WHERE dept_link="+deptid+" AND hs_id="+(prefs.getInt("hsid",0)),null);
pracur.moveToFirst();
startManagingCursor(pracur);
String[] from1 = new String[]{"practice"};
int[] to1 = new int[]{android.R.id.text1};
SimpleCursorAdapter practype =new SimpleCursorAdapter(view.getContext(),android.R.layout.simple_spinner_item, pracur, from1, to1);
practype.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
pra.setAdapter(practype);
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
});
//Practice
pra.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent,View view,int pos,long id){
practid=pra.getSelectedItemId();
//Setting the address based on the practice selected
Cursor addcur =db.rawQuery("SELECT * FROM address_masterdata WHERE practice_link="+practid,null);
addcur.moveToFirst();
startManagingCursor(addcur);
String[] from2 = new String[]{"address"};
int[] to2 = new int[]{android.R.id.text1};
SimpleCursorAdapter addtype =new SimpleCursorAdapter(view.getContext(),android.R.layout.simple_spinner_item,addcur, from2, to2);
addtype.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
add.setAdapter(addtype);
practicename=pra.getSelectedItem().toString();
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
});
//Address
add.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent,View view,int pos,long id){
addrid=add.getSelectedItemId();
addressname=add.getSelectedItem().toString();
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
});
//Getting the info
//Gender
gen.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent,View view,int pos,long id){
gender=parent.getSelectedItem().toString();
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
});
//Primary Number
prinum.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent,View view,int pos,long id){
primarynumbertype=parent.getSelectedItem().toString();
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
});
//Alternate Number
alternum.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent,View view,int pos,long id){
alternatenumbertype=parent.getSelectedItem().toString();
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
});
//Preferred Contact type
precon.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent,View view,int pos,long id){
prefferedcontactype=parent.getSelectedItem().toString();
}
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
});
//Setting the spinners based on the above variables
gen.setSelection(genpos);
prinum.setSelection(pripos);
alternum.setSelection(altpos);
precon.setSelection(prefpos);
dep.setSelection(deptpos);
pra.setSelection(practipos);
add.setSelection(addrpos);
}
第366行是SimpleCursorAdapter practype =new SimpleCursorAdapter(view.getContext(),android.R.layout.simple_spinner_item, pracur, from1, to1);
请帮助我
此致 Chinni krishna
答案 0 :(得分：1)
正如其他人所提到的，当您更改格局时，您的活动将再次创建。如果没有看到导致此问题的代码，我将无法帮助修复它。但是，如果所有其他方法都失败了，您可以在Android Manifest中的Activity上设置以下内容，以便不会在方向更改时重新创建活动：
<activity android:name="MainActivity" android:configChanges="orientation|keyboardHidden"></activity>
答案 1 :(得分：0)
我认为这是问题所在。当您旋转手机时，您的Activty正在被销毁并重建，因此它正在丢失Cursors（我猜您正在使用Cursors来访问您的数据库）。尝试关闭Cursors中的onStop()并在onStart()中创建onDestroy()（如果这不起作用，请尝试onCreate() / onPause()或onResume() / Cursor cursor = null;
修改
将其声明为您班级中的成员变量：
try {
cursor = new Cursor(blah, blah);
}
在try块中初始化：
onDestroy这位于if(cursor!=null) {
cursor.close();
}
：
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