newInstance（）的InstantiationException

25-02-27 13

在这里，我们将给大家分享关于newInstance的知识，让您更了解的InstantiationException的本质，同时也会涉及到如何更有效地AndroidRobolectric–Content

在这里，我们将给大家分享关于newInstance的知识，让您更了解的InstantiationException的本质，同时也会涉及到如何更有效地Android Robolectric – ContentProvider中queryBuilder.query()中的RuntimeException / InstantiationException、android – 当DialogFragment在顶部时,方向更改时的InstantiationException、Android’InvocationTargetException’和’UnsupportedOperationException’、Caused by: java.lang.InstantiationException: cn.at.bean.domain.ConstantInt的内容。

本文目录一览：

newInstance（）的InstantiationException
Android Robolectric – ContentProvider中queryBuilder.query()中的RuntimeException / InstantiationException
android – 当DialogFragment在顶部时,方向更改时的InstantiationException
Android’InvocationTargetException’和’UnsupportedOperationException’
Caused by: java.lang.InstantiationException: cn.at.bean.domain.ConstantInt

newInstance（）的InstantiationException

以下工作正常时，className是"java.awt.Rectangle"和"java.lang.String"等，但它失败了"java.lang.Integer"，"java.lang.Double"给java.lang.InstantiationException了classDefinition.newInstance()。

Class classs = Class.forName(className);Object object = classs.newInstance();

这是包装类或其他类的问题吗？

编辑：做到这一点的方式-学分应该去吉加尔。

Class       integerDefinition   = Class.forName("java.lang.Integer");Constructor intArgsConstructor  = integerDefinition.getConstructor(new Class[] {int.class});Object[]    intArgs             = new Object[] { new Integer(12) };Object      object              = intArgsConstructor.newInstance(intArgs);

答案1

小编典典

因为Integer没有no-
arg（default）构造函数，所以class.newInstance()将在内部调用默认构造函数

Android Robolectric – ContentProvider中queryBuilder.query()中的RuntimeException / InstantiationException

我在ContentProvider上进行了大约十次测试,只使用了sqlite; all pass保存在Content Provider的query()方法中通过queryBuilder.query()的两个.

正在测试的方法在实际应用中起作用！

这是API 17 r2和RoboLectric：
robolectric-2.0-α-3-20130417.013705-46-罐与 – dependencies.jar

@Override
public Cursor query(Uri uri,String[] projection,String selection,String[] selectionArgs,String sortOrder) {
    Log.d(Constants.TAG,"MyContentProvider.query()");
    switch(matcher.match(uri)) {
    case ITEM: // OK
        selection = "_id = ?";
        selectionArgs = new String[]{ Long.toString(ContentUris.parseId(uri)) };
    case ITEMS: // OK
        break;
    default:
        throw new IllegalArgumentException("Did not recognize URI " + uri);
    }
    // build the query with sqliteQueryBuilder
    sqliteQueryBuilder qBuilder = new sqliteQueryBuilder();
    qBuilder.setTables(TABLE_NAME);

    // query the database and get result in cursor
    final sqliteDatabase db = mDatabase.getReadableDatabase();
    Cursor resultCursor = qBuilder.query(db,// Line 112 in trace
            projection,selection,selectionArgs,null,sortOrder,null);
    resultCursor.setNotificationUri(getContext().getContentResolver(),uri);
    return resultCursor;
}

这是追溯：

java.lang.RuntimeException: java.lang.InstantiationException
    at org.robolectric.bytecode.ShadowWrangler.createShadowFor(ShadowWrangler.java:300)
    at org.robolectric.bytecode.ShadowWrangler.initializing(ShadowWrangler.java:74)
    at org.robolectric.bytecode.RobolectricInternals.initializing(RobolectricInternals.java:90)
    at android.database.sqlite.sqliteQuery.$$robo$init(sqliteQuery.java)
    at android.database.sqlite.sqliteClosable.<init>(sqliteClosable.java:26)
    at android.database.sqlite.sqliteProgram.<init>(sqliteProgram.java:41)
    at android.database.sqlite.sqliteQuery.<init>(sqliteQuery.java:37)
    at android.database.sqlite.sqliteDirectCursorDriver.query(sqliteDirectCursorDriver.java:44)
    at android.database.sqlite.sqliteDatabase.rawQueryWithFactory(sqliteDatabase.java:1314)
    at android.database.sqlite.sqliteQueryBuilder.query(sqliteQueryBuilder.java:400)
    at android.database.sqlite.sqliteQueryBuilder.query(sqliteQueryBuilder.java:333)
    at com.example.readingsprovider.ReadingsContentProvider.query(ReadingsContentProvider.java:112)
    at com.example.readingsprovider.test.ContentProviderTest.testUpdateMultipleWithoutWhere(ContentProviderTest.java:110)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
    at org.robolectric.RobolectricTestRunner$2.evaluate(RobolectricTestRunner.java:267)
    at org.junit.runners.BlockJUnit4ClassRunner.runNotIgnored(BlockJUnit4ClassRunner.java:79)
    at org.junit.runners.BlockJUnit4ClassRunner.runchild(BlockJUnit4ClassRunner.java:71)
    at org.junit.runners.BlockJUnit4ClassRunner.runchild(BlockJUnit4ClassRunner.java:49)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
    at org.junit.runners.ParentRunner.runchildren(ParentRunner.java:191)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
    at org.robolectric.RobolectricTestRunner$1.evaluate(RobolectricTestRunner.java:202)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: java.lang.InstantiationException
    at sun.reflect.InstantiationExceptionConstructorAccessorImpl.newInstance(InstantiationExceptionConstructorAccessorImpl.java:30)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
    at java.lang.class.newInstance0(Class.java:357)
    at java.lang.class.newInstance(Class.java:310)
    at org.robolectric.bytecode.ShadowWrangler.createShadowFor(ShadowWrangler.java:293)
    at org.robolectric.bytecode.ShadowWrangler.initializing(ShadowWrangler.java:74)
    at org.robolectric.bytecode.RobolectricInternals.initializing(RobolectricInternals.java:90)
    at android.database.sqlite.sqliteQuery.$$robo$init(sqliteQuery.java)
    at android.database.sqlite.sqliteClosable.<init>(sqliteClosable.java:26)
    at android.database.sqlite.sqliteProgram.<init>(sqliteProgram.java:41)
    at android.database.sqlite.sqliteQuery.<init>(sqliteQuery.java:37)
    at android.database.sqlite.sqliteDirectCursorDriver.$$robo$$sqliteDirectCursorDriver_7ac1_query(sqliteDirectCursorDriver.java:44)
    at android.database.sqlite.sqliteDirectCursorDriver.query(sqliteDirectCursorDriver.java)
    at android.database.sqlite.sqliteDatabase.$$robo$$sqliteDatabase_ab15_rawQueryWithFactory(sqliteDatabase.java:1314)
    at android.database.sqlite.sqliteDatabase.rawQueryWithFactory(sqliteDatabase.java)
    at android.database.sqlite.sqliteQueryBuilder.$$robo$$sqliteQueryBuilder_ba4d_query(sqliteQueryBuilder.java:400)
    at android.database.sqlite.sqliteQueryBuilder.query(sqliteQueryBuilder.java)
    at android.database.sqlite.sqliteQueryBuilder.$$robo$$sqliteQueryBuilder_ba4d_query(sqliteQueryBuilder.java:333)
    at android.database.sqlite.sqliteQueryBuilder.query(sqliteQueryBuilder.java)
    at com.example.readingsprovider.ReadingsContentProvider.query(ReadingsContentProvider.java:112)
    at com.example.readingsprovider.test.ContentProviderTest.testUpdateMultipleWithoutWhere(ContentProviderTest.java:110)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    ... 21 more

可以告诉我这是否是Robolectric的限制,还是我的不好？非常感谢！

附：如果Reflection API将失败的类名放在InstantiationException消息中,难道不是梦幻般的吗？

解决方法

我的项目有同样的问题,终于能够用一些谷歌搜索和U Avalos的前一个答案来解决它

1.创建自定义sqliteShadow

@Implements(value = sqliteDatabase.class,inheritImplementationMethods = true)
public class CustomsqliteShadow extends ShadowsqliteDatabase {

    @Implementation
    public Cursor rawQueryWithFactory (sqliteDatabase.CursorFactory cursorFactory,String sql,String editTable,CancellationSignal cancellationSignal) {
      return rawQueryWithFactory(cursorFactory,sql,editTable);
    }
}

2.将@Config注释添加到测试中

要使用自定义阴影类,可以在robolectric2中使用@Config注释

@RunWith(RobolectricTestRunner.class)
@Config( shadows = {CustomsqliteShadow.class})
public class ContentProviderTest {

参考

http://robolectric.blogspot.co.at/2013/05/configuring-robolectric-20.html

android – 当DialogFragment在顶部时,方向更改时的InstantiationException

我的Fragment类中有一个DialogFragment被定义为内部类.即使出现以下异常,方向更改：

Caused by: android.app.Fragment$InstantiationException: Unable to instantiate fragment my.package.fragments.ImportFragment$FailedImportDialog: make sure class name exists,is public,and has an empty constructor that is public
        at android.app.Fragment.instantiate(Fragment.java:585)
        at android.app.FragmentState.instantiate(Fragment.java:96)
        at android.app.FragmentManagerImpl.restoreAllState(FragmentManager.java:1682)
        at android.app.Activity.onCreate(Activity.java:861)
        at my.package.activities.ImportActivity.onCreate(ImportActivity.java:8)
        at android.app.Activity.performCreate(Activity.java:4465)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
        at android.app.ActivityThread.performlaunchActivity(ActivityThread.java:1920)
        ... 12 more
        Caused by: java.lang.InstantiationException: can't instantiate class my.package.fragments.ImportFragment$FailedImportDialog; no empty constructor
        at java.lang.class.newInstanceImpl(Native Method)
        at java.lang.class.newInstance(Class.java:1319)
        at android.app.Fragment.instantiate(Fragment.java:574)

但我有公共建设者：

class FailedImportDialog extends DialogFragment {

        private EditText edtPassword;
        private Button button;

        public FailedImportDialog() { // Here it is!
        }

        @Override
        public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState) {
            View v = inflater.inflate(R.layout.another_password_dialog,container,false);
            edtPassword = (EditText) v.findViewById(R.id.another_password_dialog_et_password);

            getDialog().setTitle(R.string.Failed_to_decrypt);

            Button button = (Button) v.findViewById(R.id.another_password_dialog_btn_ok);
            button.setonClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {

            });

            return v;

    }
}

这是xml：

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent"
              android:orientation="vertical"
              android:padding="10dp">

    <TextView android:id="@+id/another_password_dialog_tv_text"
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:text="@string/what_password_did_you_use">
    </TextView>

    <EditText android:id="@+id/another_password_dialog_et_password"
              android:layout_height="wrap_content"
              android:layout_width="match_parent"
              android:inputType="textPassword">
        <requestFocus>
        </requestFocus>
    </EditText>

    <Button android:id="@+id/another_password_dialog_btn_ok"
            android:layout_height="wrap_content"
            android:layout_width="match_parent"
            android:text="OK">
    </Button>

</LinearLayout>

你们知道为什么会发生这种异常吗？谢谢！

更新：如果我将一个类移动到一个单独的文件,没有这样的例外,一切顺利.所以问题是 – 当DialogFragment是一个内部类时,为什么会发生这种异常？

解决方法

尝试使内部类静态：

public static class FailedImportDialog extends DialogFragment

我会稍后再发布一些有关这方面的解释.在此期间,尝试这个,让我知道如果它的作品.

Android’InvocationTargetException’和’UnsupportedOperationException’

我在OPPO X905和OPPO X907上遇到了问题,两者都是 Android 4.0.3(API等级15),我没有使用任何更高级别的API,我在Google和SO上搜索过,都与我的问题不同,下面是我的xml文件和崩溃日志,在此先感谢.
xml文件:(分隔符的边距最初是7.5dp,这可能是问题吗？)

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/item_full"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="#eff0f7"
    android:baselineAligned="false"
    android:orientation="vertical" >
    <RelativeLayout
        android:id="@+id/item_first_half"
        android:layout_width="match_parent"
        android:layout_height="36dp"
        android:orientation="vertical" >
        <View
            android:id="@+id/first_path"
            android:layout_width="4dp"
            android:layout_height="4dp"
            android:layout_marginLeft="40dp"
            android:layout_marginStart="40dp"
            android:background="@drawable/selector_car_action_path" />
        <ImageView
            android:id="@+id/im_car_direction_icon"
            android:layout_width="28dp"
            android:layout_height="28dp"
            android:layout_gravity="top"
            android:layout_marginLeft="28dp"
            android:layout_marginStart="28dp"
            android:layout_marginTop="4dp"
            android:background="@drawable/selector_car_action_background"
            android:padding="2dp"
            android:src="@drawable/selector_navi_icon_63" />
        <View
            android:id="@+id/second_path"
            android:layout_width="4dp"
            android:layout_height="4dp"
            android:layout_below="@id/im_car_direction_icon"
            android:layout_marginLeft="40dp"
            android:layout_marginStart="40dp"
            android:background="@drawable/selector_car_action_path" />
        <TextView
            android:id="@+id/tv_direction"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_centerVertical="true"
            android:layout_marginEnd="15dp"
            android:layout_marginLeft="68dp"
            android:layout_marginRight="15dp"
            android:layout_marginStart="68dp"
            android:singleLine="true"
            android:text=""
            android:textColor="@drawable/selector_car_route_turn_text"
            android:textSize="16sp" />
    </RelativeLayout>
    <RelativeLayout
        android:id="@+id/item_second_half"
        android:layout_width="match_parent"
        android:layout_height="32dp" >
        <View
            android:id="@+id/third_path"
            android:layout_width="4dp"
            android:layout_height="match_parent"
            android:layout_marginLeft="40dp"
            android:layout_marginStart="40dp"
            android:background="@drawable/selector_car_action_path" />
        <TextView
            android:id="@+id/tv_road_name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="68dp"
            android:layout_marginStart="68dp"
            android:layout_marginTop="4dp"
            android:singleLine="true"
            android:text=""
            android:textColor="@drawable/selector_car_route_desc"
            android:textSize="16sp" />
        <TextView
            android:id="@+id/divider_for_road_and_distance"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:layout_marginEnd="7dp"
            android:layout_marginLeft="7dp"
            android:layout_marginRight="7dp"
            android:layout_marginStart="7dp"
            android:layout_marginTop="4dp"
            android:layout_toEndOf="@id/tv_road_name"
            android:layout_toRightOf="@id/tv_road_name"
            android:singleLine="true"
            android:text="|"
            android:textColor="@drawable/selector_car_route_desc"
            android:textSize="16sp" />
        <TextView
            android:id="@+id/tv_ride_distance"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginEnd="15dp"
            android:layout_marginRight="15dp"
            android:layout_marginTop="4dp"
            android:layout_toEndOf="@id/divider_for_road_and_distance"
            android:layout_toRightOf="@id/divider_for_road_and_distance"
            android:singleLine="true"
            android:text=""
            android:textColor="@drawable/selector_car_route_desc"
            android:textSize="16sp" />
        <View
            android:layout_width="match_parent"
            android:layout_height="1px"
            android:layout_alignParentBottom="true"
            android:layout_marginEnd="15dp"
            android:layout_marginLeft="68dp"
            android:layout_marginRight="15dp"
            android:layout_marginStart="68dp"
            android:background="#dee1f0" />
    </RelativeLayout>
</LinearLayout>

drawable / selector_car_route_desc文件是

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:state_selected="true" android:color="@color/color_999999"/>
    <item android:state_selected="false" android:color="@color/color_333333"/>

</selector>

崩溃日志：

android.view.InflateException: Binary XML file line #106: Error inflating class <unkNown>
android.view.LayoutInflater.createView(LayoutInflater.java:606)
com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:56)
android.view.LayoutInflater.onCreateView(LayoutInflater.java:653)
android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:678)
android.view.LayoutInflater.rInflate(LayoutInflater.java:739)
android.view.LayoutInflater.rInflate(LayoutInflater.java:742)
android.view.LayoutInflater.inflate(LayoutInflater.java:489)
android.view.LayoutInflater.inflate(LayoutInflater.java:396)
android.view.LayoutInflater.inflate(LayoutInflater.java:352)
com.tencent.map.ama.route.ui.view.e.<init>(CarRouteShowItem.java:78)
com.tencent.map.ama.route.ui.view.f.a(CarRouteShowView.java:100)
com.tencent.map.ama.route.ui.view.d.a(CarRouteDetailView.java:37)
com.tencent.map.ama.route.ui.MapStateCarRoute.e(MapStateCarRoute.java:418)
com.tencent.map.ama.route.ui.MapStateCarRoute$1.run(MapStateCarRoute.java:255)
android.os.Handler.handleCallback(Handler.java:605)
android.os.Handler.dispatchMessage(Handler.java:92)
android.os.Looper.loop(Looper.java:137)
android.app.ActivityThread.main(ActivityThread.java:4476)
java.lang.reflect.Method.invokeNative(Native Method)
java.lang.reflect.Method.invoke(Method.java:511)
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:808)
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:575)
dalvik.system.NativeStart.main(Native Method)
cause by:
java.lang.reflect.InvocationTargetException: null
java.lang.reflect.Constructor.constructNative(Native Method)
java.lang.reflect.Constructor.newInstance(Constructor.java:417)
android.view.LayoutInflater.createView(LayoutInflater.java:586)
com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:56)
android.view.LayoutInflater.onCreateView(LayoutInflater.java:653)
android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:678)
android.view.LayoutInflater.rInflate(LayoutInflater.java:739)
android.view.LayoutInflater.rInflate(LayoutInflater.java:742)
android.view.LayoutInflater.inflate(LayoutInflater.java:489)
android.view.LayoutInflater.inflate(LayoutInflater.java:396)
android.view.LayoutInflater.inflate(LayoutInflater.java:352)
com.tencent.map.ama.route.ui.view.e.<init>(CarRouteShowItem.java:78)
com.tencent.map.ama.route.ui.view.f.a(CarRouteShowView.java:100)
com.tencent.map.ama.route.ui.view.d.a(CarRouteDetailView.java:37)
com.tencent.map.ama.route.ui.MapStateCarRoute.e(MapStateCarRoute.java:418)
com.tencent.map.ama.route.ui.MapStateCarRoute$1.run(MapStateCarRoute.java:255)
android.os.Handler.handleCallback(Handler.java:605)
android.os.Handler.dispatchMessage(Handler.java:92)
android.os.Looper.loop(Looper.java:137)
android.app.ActivityThread.main(ActivityThread.java:4476)
java.lang.reflect.Method.invokeNative(Native Method)
java.lang.reflect.Method.invoke(Method.java:511)
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:808)
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:575)
dalvik.system.NativeStart.main(Native Method)
cause by:
java.lang.UnsupportedOperationException: Can''t convert to dimension: type=0x12
android.content.res.TypedArray.getDimensionPixelSize(TypedArray.java:463)
android.view.View.<init>(View.java:2849)
android.widget.TextView.<init>(TextView.java:499)
android.widget.TextView.<init>(TextView.java:492)
java.lang.reflect.Constructor.constructNative(Native Method)
java.lang.reflect.Constructor.newInstance(Constructor.java:417)
android.view.LayoutInflater.createView(LayoutInflater.java:586)
com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:56)
android.view.LayoutInflater.onCreateView(LayoutInflater.java:653)
android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:678)
android.view.LayoutInflater.rInflate(LayoutInflater.java:739)
android.view.LayoutInflater.rInflate(LayoutInflater.java:742)
android.view.LayoutInflater.inflate(LayoutInflater.java:489)
android.view.LayoutInflater.inflate(LayoutInflater.java:396)
android.view.LayoutInflater.inflate(LayoutInflater.java:352)
com.tencent.map.ama.route.ui.view.e.<init>(CarRouteShowItem.java:78)
com.tencent.map.ama.route.ui.view.f.a(CarRouteShowView.java:100)
com.tencent.map.ama.route.ui.view.d.a(CarRouteDetailView.java:37)
com.tencent.map.ama.route.ui.MapStateCarRoute.e(MapStateCarRoute.java:418)
com.tencent.map.ama.route.ui.MapStateCarRoute$1.run(MapStateCarRoute.java:255)
android.os.Handler.handleCallback(Handler.java:605)
android.os.Handler.dispatchMessage(Handler.java:92)
android.os.Looper.loop(Looper.java:137)
android.app.ActivityThread.main(ActivityThread.java:4476)
java.lang.reflect.Method.invokeNative(Native Method)
java.lang.reflect.Method.invoke(Method.java:511)
com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:808)
com.android.internal.os.ZygoteInit.main(ZygoteInit.java:575)
dalvik.system.NativeStart.main(Native Method)

CarRouteShowItem.java:78的代码是这样的：

View mView = LayoutInflater.from(mContext).inflate(R.layout.car_route_detail_item,null);

CarRouteShowItem不是View的子代,其代码如下：

public class CarRouteShowItem {

    private Context mContext;

    private View mView;

    public CarRouteShowItem(Context context) {
        mContext = context;

        // mView is used by caller 
        mView = LayoutInflater.from(mContext).inflate(R.layout.car_route_detail_item,null);

        // some view finds 
    }

        // some other methods related with specific logic
}

图形布局可以在Eclipse中从API级别8预览到API级别23,但是当我在API级别15的Android Studio中预览时,它会显示错误消息：无法解析资源@style / Widget.TextView,其他API级别没问题,但我没有使用TextView的样式.

解决方法

你需要的只是一个额外的眼睛:-)

android:layout_height="1px"

希望你现在能看到.第二个RelativeLayout中的最后一个子项,其id为item_second_half,类型为< View,将其更改为

android:layout_height="1dp"

让我尽快回顾一下

Caused by: java.lang.InstantiationException: cn.at.bean.domain.ConstantInt


org.springframework.jdbc.UncategorizedSQLException: ConnectionCallback; uncategorized SQLException for SQL []; SQL state [null]; error code [0]; java.lang.InstantiationException: cn.at.bean.domain.ConstantInt; nested exception is java.sql.SQLException: java.lang.InstantiationException: cn.at.bean.domain.ConstantInt
     at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:83)
     at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80)
     at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:80)
     at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:349)
     at cn.at.mo.framework.dao.AbstractStorage.execute(AbstractStorage.java:133)
     at cn.at.mo.framework.dao.AbstractStorage.execute(AbstractStorage.java:168)
     at cn.at.mo.framework.dao.AbstractStorage.executeQuery(AbstractStorage.java:93)
     at cn.at.mo.framework.dao.dao.impl.AbstractDao.findBySql(AbstractDao.java:367)
     at cn.at.dao.ConstantIntDao.getCommentId(ConstantIntDao.java:43)
     at cn.at.dao.TestConstantIntDao.testGetCommentId(TestConstantIntDao.java:41)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:601)
     at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
     at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
     at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
     at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
     at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
     at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:74)
     at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
     at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:83)
     at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:72)
     at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:231)
     at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:88)
     at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
     at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
     at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
     at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
     at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
     at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
     at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:71)
     at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
     at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:174)
     at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
     at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)
Caused by: java.sql.SQLException: java.lang.InstantiationException: cn.at.bean.domain.ConstantInt
     at cn.at.mo.framework.dao.CrudBuilder.from(CrudBuilder.java:471)
     at cn.at.mo.framework.dao.dao.impl.AbstractDao.from(AbstractDao.java:398)
     at cn.at.mo.framework.dao.dao.impl.AbstractDao$5.execute(AbstractDao.java:371)
     at cn.at.mo.framework.dao.AbstractStorage$5.execute(AbstractStorage.java:102)
     at cn.at.mo.framework.dao.AbstractStorage$8.execute(AbstractStorage.java:172)
     at cn.at.mo.framework.dao.AbstractStorage$7.doInConnection(AbstractStorage.java:136)
     at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:342)
     ... 36 more
Caused by: java.lang.InstantiationException: cn.at.bean.domain.ConstantInt
     at java.lang.Class.newInstance0(Class.java:357)
     at java.lang.Class.newInstance(Class.java:325)
     at cn.at.mo.framework.dao.CrudBuilder.from(CrudBuilder.java:426)
     ... 42 more

每个bean对象都应该有一个默认无参数的构造方法负责查询的时候通过反射的方式实例化的时候就会抛出无法实例化的情况

今天关于newInstance和的InstantiationException的分享就到这里，希望大家有所收获，若想了解更多关于Android Robolectric – ContentProvider中queryBuilder.query()中的RuntimeException / InstantiationException、android – 当DialogFragment在顶部时,方向更改时的InstantiationException、Android’InvocationTargetException’和’UnsupportedOperationException’、Caused by: java.lang.InstantiationException: cn.at.bean.domain.ConstantInt等相关知识，可以在本站进行查询。

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