（活动（上下文））。getIntent（）。getExtras（）返回null

Question

我试图从上下文（在类的主构造函数中传递）中获取包引用，以获取不同类中的参数。不幸的是，我总是得到空指针异常。我不太确定为什么会这样，因为我以同样的方式获得fragmentManager的成功引用

这里是Fragement“ Config”中的“ Request”类的调用。我检查过了，那个背景！！不为空

Answer 1

已解决：问题出在我的Intent课堂上，我忘了在此intent中放一些额外内容。

意图类：

fun putExtras(extras: Bundle){
    intent.putExtras(extras)
}

在FragmentOperation类中

Intent(context).putExtras(bundle)

然后其余代码起作用

原始代码

1）

配置类

class Config : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.config)
        FragmentOperation(this@Config).organizationNameConfig()
    }

    override fun onBackPressed() {
        val dialog = Dialog(this@Config, getString(R.string.titleCancelConfiguration), getString(R.string.messageCancelConfiguration), R.drawable.round_exit_to_app_white_48, 2)
        dialog.setLeftButtonText(R.string.yes)
        dialog.getLeftButton().setOnClickListener {
            dialog.dismiss()
            finish()
        }
        dialog.setRightButtonText(R.string.back)
        dialog.getRightButton().setOnClickListener {
            dialog.dismiss()
        }
    }
}

ConfigFindOrganization片段

class ConfigFindOrganization{

override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
                          savedInstanceState: Bundle?): View? {
    return inflater.inflate(R.layout.config_database, container, false)
}

override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
    super.onViewCreated(view, savedInstanceState)
    activity!!.findViewById<Button>(R.id.configConfirm).setOnClickListener {
        if (inputIsValid()) {
            Request(context!!).findOrganization(organizationName.text.toString())
        }
    }
}

private fun inputIsValid(): Boolean {
    val validation = Validation(context!!)
    validation.checkEditTextInput(organizationName, R.string.inputDatabaseAddress)
    return validation.inputIsValid()
}

请求类

public class Request {
    private Context context;
    private Arguments arguments;

    public Request(Context context) {
        this.context = context;
        this.arguments = new Arguments(((Activity) context).getIntent().getExtras()); -> Here is the error
        try {

        } catch (Exception e) {
            Log.i("output", "no arguments has been found " + e.toString());
        }
        setBasicParams();
    }
}

参数类

class Arguments(private val bundle: Bundle) {} -> null value is passed 

2）

--------- beginning of crash
E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.flashit.attendance, PID: 9636
java.lang.IllegalArgumentException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull, parameter bundle
    at com.flashit.attendance.Arguments.<init>(Arguments.kt:5)
    at com.flashit.attendance.Request.<init>(Request.java:48)
    at com.flashit.attendance.ConfigFindOrganization$onViewCreated$1.onClick(ConfigFindOrganization.kt:24)
    at android.view.View.performClick(View.java:6597)
    at android.view.View.performClickInternal(View.java:6574)
    at android.view.View.access$3100(View.java:778)
    at android.view.View$PerformClick.run(View.java:25885)
    at android.os.Handler.handleCallback(Handler.java:873)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:193)
    at android.app.ActivityThread.main(ActivityThread.java:6669)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

3）是的，但是我在代码中看不到任何错误

Answer 2

尝试在调试器下逐步完成此操作：

public class Request {
   private Context context;
   ...
   public Request(Context context) {
      this.context = context;
      try {
         Intent intent = context.getIntent();
         Bundle extras = intent.getExtras();   // <-- I'll betcha' this is returning "null"
         this.arguments = new Arguments(extras);
         ...
      } catch (Exception e) {
         Log.i("output", "no arguments has been found " + e.toString());
      }
      ...