小编Mik*_* M.的帖子

我想交换月份和日期（微调器）。我想将日期列 (Spinner) 发送到左侧，将月份列 (Spinner) 发送到中间。是否可以？

我想在一个自定义Dialog中显示 2 个选项卡Activity，但出现以下错误。

错误：

No view found for id 0x7f0f0134 (com.hiro.chatio:id/viewPage_theme) for fragment
    PostColorPickerFragment{35ffefce #0 id=0x7f0f0134 android:switcher:2131689780:0}
java.lang.IllegalArgumentException: No view found for id 0x7f0f0134 (com.hiro.chatio:id/viewPage_theme)
    for fragment PostColorPickerFragment{35ffefce #0 id=0x7f0f0134 android:switcher:2131689780:0}

MainActivity：

private Button pick_color;

@Override
protected void onCreate(final Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_create_blog); 

    pick_color = (Button) findViewById(R.id.create_blog_color_btn);

    pick_color.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            final Dialog dialog = new Dialog(CreateBlogActivity.this);
            dialog.setContentView(R.layout.blog_theme_picker);
            dialog.setCanceledOnTouchOutside(false);

            dialog.getWindow().getAttributes().windowAnimations = R.style.SlideUpDialogAnimation;

            Button pickColor = (Button) dialog.findViewById(R.id.pick_color_btn);
            Button default_color …

我试图创建一个Spinner内部，Fragment但是在ArrayAdapter构造函数调用中出现错误。我不知道为什么，但是有红色下划线。除此之外，没有错误。当我在中使用相同功能ArrayAdapter时Activity，但在中使用时Fragment，则出现错误。

我的FirstFragment.kt：

class FirstFragment : Fragment() {

    private var mListener: OnFragmentInteractionListener? = null

    override fun onCreateView(inflater: LayoutInflater?, container: ViewGroup?, savedInstanceState: Bundle?): View? {
        // Inflate the layout for this fragment
        return inflater!!.inflate(R.layout.fragment_first, container, false)
    }

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

        /*Find the id of spinner*/
        val spinner = lol

        /*set an adapter with strings array*/
        spinner.adapter = ArrayAdapter(this, R.layout.support_simple_spinner_dropdown_item, resources.getStringArray(R.array.atoms)) as SpinnerAdapter? …

为什么NullPointerException我ViewHolder的bindItems()方法中会出现 a ？

我已经突出显示了我获得NullPointerException. 该blogpost_authorID存在，因为你可以在XML中看到的，所以这里有什么问题吗？findViewById<TextView>(R.id.blogpost_author)返回空值如何？

Adapter和ViewHolder代码：

class BlogPostAdapter(val blogList: ArrayList<BlogPost>) : RecyclerView.Adapter<BlogPostAdapter.ViewHolder>() {

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int) : BlogPostAdapter.ViewHolder {
        val v = LayoutInflater.from(parent.context).inflate(R.layout.blog_post_list, parent, false)
        return ViewHolder(v)
    }

    override fun getItemCount(): Int {
        return blogList.size
    }

    override fun onBindViewHolder(holder: BlogPostAdapter.ViewHolder, position: Int) {
        holder.bindItems(blogList[position])
    }

    class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
        fun bindItems(blogPost: BlogPost) {
            val blogPostAuthor = itemView.findViewById<TextView>(R.id.blogpost_author) // THIS LINE …

该应用程序适用于以前版本的 Android，但不适用于 Oreo。这是一个WebView与Notifications。我一直在研究这个错误，但没有发现任何类似的东西。

堆栈跟踪：

E/AndroidRuntime: FATAL EXCEPTION: main
Process: net.oneteamit.tk, PID: 3171
java.lang.RuntimeException: Unable to start activity ComponentInfo{net.oneteamit.tk/net.oneteamit.tk.MainActivity}:
    java.lang.IllegalArgumentException
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2817)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892)
    at android.app.ActivityThread.-wrap11(Unknown Source:0)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593)
    at android.os.Handler.dispatchMessage(Handler.java:105)
    at android.os.Looper.loop(Looper.java:164)
    at android.app.ActivityThread.main(ActivityThread.java:6541)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:240)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:767)
 Caused by: java.lang.IllegalArgumentException
    at android.os.Parcel.readException(Parcel.java:1946)
    at android.os.Parcel.readException(Parcel.java:1888)
    at android.app.INotificationManager$Stub$Proxy.createNotificationChannels(INotificationManager.java:1418)
    at android.app.NotificationManager.createNotificationChannels(NotificationManager.java:446)
    at android.app.NotificationManager.createNotificationChannel(NotificationManager.java:434)
    at net.oneteamit.tk.MainActivity.onCreate(MainActivity.java:47)
    at android.app.Activity.performCreate(Activity.java:6975)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1213)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2770)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2892) 
    at android.app.ActivityThread.-wrap11(Unknown Source:0) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1593) 
    at android.os.Handler.dispatchMessage(Handler.java:105) 
    at android.os.Looper.loop(Looper.java:164) 
    at android.app.ActivityThread.main(ActivityThread.java:6541) 
    at …

我正在使用Android Studio 1.4.1,我刚刚创建了一个Hashmap,并且正在关注如何填充和操作它的教程(在java上).但是我得到一个'无法解决符号放置'错误,而"put"命令为红色.我添加的图像显示了自动完成快照,虽然导入了java.util.HashMap,但自动完成中没有"put"命令.可用命令也以红色显示.我尝试使用它们而不是"put"命令.我一直都有这种问题.有人可以帮忙吗？先感谢您...

import java.util.HashMap;

HashMap<String, String> pozisyon = new HashMap<String, String>();
pozisyon.put("SKale", "a8");

我在我的应用程序中遇到以下错误,我认为这与我编写布局文件的方式有关,或者在我的代码中使用它们.

05-31 13:39:59.283: E/AndroidRuntime(332): Uncaught handler: thread main exiting due to uncaught exception
05-31 13:39:59.293: E/AndroidRuntime(332): java.lang.NullPointerException
05-31 13:39:59.293: E/AndroidRuntime(332):  at com.dd.qsg.ShowAchievements$AchievementAdapter.bindView(ShowAchievements.java:38)
05-31 13:39:59.293: E/AndroidRuntime(332):  at android.widget.CursorAdapter.getView(CursorAdapter.java:186)
05-31 13:39:59.293: E/AndroidRuntime(332):  at android.widget.AbsListView.obtainView(AbsListView.java:1274)
05-31 13:39:59.293: E/AndroidRuntime(332):  at android.widget.ListView.measureHeightOfChildren(ListView.java:1147)
05-31 13:39:59.293: E/AndroidRuntime(332):  at android.widget.ListView.onMeasure(ListView.java:1060)
05-31 13:39:59.293: E/AndroidRuntime(332):  at android.view.View.measure(View.java:7964)
05-31 13:39:59.293: E/AndroidRuntime(332):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3023)
05-31 13:39:59.293: E/AndroidRuntime(332):  at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:888)
05-31 13:39:59.293: E/AndroidRuntime(332):  at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:619)
05-31 13:39:59.293: E/AndroidRuntime(332):  at android.widget.LinearLayout.onMeasure(LinearLayout.java:280)
05-31 13:39:59.293: E/AndroidRuntime(332):  at android.view.View.measure(View.java:7964)
05-31 13:39:59.293: E/AndroidRuntime(332):  at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3023)
05-31 13:39:59.293: E/AndroidRuntime(332): …