如何使用kotlin使用光标加载器

Question

我尝试将我的java项目转换为kotlin，但是有一个问题让我困惑。
项目结构：

App：应用程序用来声明全局变量
MainActivity：AppCompatActivity
Provider：ContentProvider的
SectionsPagerAdapter：FragmentPagerAdapter
fragment0：
fragment1：片段器具LoaderManager.LoaderCallbacks

当我尝试将fragment1转换为kotlin，它徘徊FC。
片段1 java代码：

class fragment1 : Fragment(), LoaderManager.LoaderCallbacks<Cursor> { 
private var mMainView: View? = null 
private var adapter: SimpleCursorAdapter? = null 
private var cursor: Cursor? = null 
private var date: Date? = null 
private var kadaihao: Array<String?>? = null 
private val uri: Uri? = null 

override fun onCreate(savedInstanceState: Bundle?) { 
    super.onCreate(savedInstanceState) 
    val inflater = activity.layoutInflater 
    mMainView = inflater.inflate(R.layout.fragment1, activity.findViewById(R.id.container) as ViewGroup, false) 
} 

override fun onCreateView(inflater: LayoutInflater?, container: ViewGroup?, 
          savedInstanceState: Bundle?): View? { 
    return mMainView 
} 

override fun onViewCreated(view: View?, savedInstanceState: Bundle?) { 
    super.onViewCreated(view, savedInstanceState) 

    val lv = mMainView!!.findViewById(R.id.lv1) as ListView 
    val uiBindFrom = arrayOf("_id", "shuakae", "kadaihao", "shijian", "feilv", "beizhu") 
    val uiBindTo = intArrayOf(R.id.ID1, R.id.tv_shuakae1, R.id.tv_kadaihao1, R.id.tv_shijian1, R.id.tv_feilv1, R.id.tv_beizhu1) 
    loaderManager.initLoader(1, null, this) 
    adapter = SimpleCursorAdapter(
      context, R.layout.item_zhangdan, null, uiBindFrom, uiBindTo, 
      CursorAdapter.FLAG_REGISTER_CONTENT_OBSERVER) 
    lv.adapter = adapter 
} 

override fun onCreateLoader(id: Int, args: Bundle): Loader<Cursor> { 
    val projection = arrayOf("_id", "shuakae", "kadaihao", "shijian", "feilv", "beizhu") 
    val selection = "yihuan=0" 
    return CursorLoader(context, App.Uri_ZhangDan, projection, selection, null, "kadaihao asc,shijian desc") 
} 

override fun onLoadFinished(loader: Loader<Cursor>, data: Cursor) { 
    adapter!!.swapCursor(data) 
} 

override fun onLoaderReset(loader: Loader<Cursor>) { 
    adapter!!.swapCursor(null) 
} 
} 

尝试运行它，并抛出FC：

java.lang.IllegalArgumentException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull, parameter args 
at com.codeme.ccm.fragment1.onCreateLoader(fragment1.kt:0) 
at android.support.v4.app.LoaderManagerImpl.createLoader(LoaderManager.java:539) 
at android.support.v4.app.LoaderManagerImpl.createAndInstallLoader(LoaderManager.java:548) 
at android.support.v4.app.LoaderManagerImpl.initLoader(LoaderManager.java:603) 
at com.codeme.ccm.fragment1.onViewCreated(fragment1.kt:73) 
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1314) 
at android.support.v4.app.FragmentManagerImpl.moveFragmentToExpectedState(FragmentManager.java:1528) 
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1595) 
at android.support.v4.app.BackStackRecord.executeOps(BackStackRecord.java:758) 
at android.support.v4.app.FragmentManagerImpl.executeOps(FragmentManager.java:2363) 
at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2149) 
at android.support.v4.app.FragmentManagerImpl.optimizeAndExecuteOps(FragmentManager.java:2103) 
at android.support.v4.app.FragmentManagerImpl.execSingleAction(FragmentManager.java:1984) 
at android.support.v4.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:626) 
at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:143) 
at android.support.v4.view.ViewPager.populate(ViewPager.java:1268) 
at android.support.v4.view.ViewPager.populate(ViewPager.java:1116) 
at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1642) 
at android.view.View.measure(View.java:18811) 
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952) 
at android.support.design.widget.CoordinatorLayout.onMeasureChild(CoordinatorLayout.java:714) 
at android.support.design.widget.HeaderScrollingViewBehavior.onMeasureChild(HeaderScrollingViewBehavior.java:90) 
at android.support.design.widget.AppBarLayout$ScrollingViewBehavior.onMeasureChild(AppBarLayout.java:1391) 
at android.support.design.widget.CoordinatorLayout.onMeasure(CoordinatorLayout.java:784) 
at android.view.View.measure(View.java:18811) 
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952) 
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194) 
at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:139) 
at android.view.View.measure(View.java:18811) 
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952) 
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465) 
at android.widget.LinearLayout.measureVertical(LinearLayout.java:748) 
at android.widget.LinearLayout.onMeasure(LinearLayout.java:630) 
at android.view.View.measure(View.java:18811) 
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952) 
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194) 
at android.view.View.measure(View.java:18811) 
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952) 
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465) 
at android.widget.LinearLayout.measureVertical(LinearLayout.java:748) 
at android.widget.LinearLayout.onMeasure(LinearLayout.java:630) 
at android.view.View.measure(View.java:18811) 
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952) 
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194) 
at com.android.internal.policy.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2643) 
at android.view.View.measure(View.java:18811) 
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2127) 
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1243) 
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1479) 
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1134) 
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6050) 
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:860) 
at android.view.Choreographer.doCallbacks(Choreographer.java:672) 
at android.view.Choreographer.doFrame(Choreographer.java:608) 
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:846) 
at android.os.Handler.handleCallback(Handler.java:742) 
at android.os.Handler.dispatchMessage(Handler.java:95) 
at android.os.Looper.loop(Looper.java:154) 
at android.app.ActivityThread.main(ActivityThread.java:5524) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:740) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:630) 

如何解决呢？

Answer 1

我没有在Android中使用CursorLoader做很多事情，但是通过堆栈跟踪来判断它看起来像Bundle参数可以为null，但是您声明它为非空值，所以Kotlin插入了一些检查来验证这一点。

尝试改变

override fun onCreateLoader(id: Int, args: Bundle) 

到

override fun onCreateLoader(id: Int, args: Bundle?)