Question

所以我有这个微调器，我想找到所选项目的内容。我有一些东西可以记住所选项目。现在有一个按钮可以在微调器所在的同一布局中单击，这将弹出一个对话框，告诉您选择了哪个项目。但我收到错误，在我的日志猫上说它＆＃34; java.lang.NullPointerException＆＃34;

这是对话框的XML文件;

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#ffc0c0c0">

<TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Saving&apos;s Account"
            android:id="@+id/spinnerSelectedText"
            android:textColor="#ff000000"
            android:drawableLeft="@drawable/transferaccount_icon"
            android:drawablePadding="10dp"
            android:paddingLeft="10dp"
            android:layout_marginTop="10dp"
            android:textSize="16sp" />


</RelativeLayout>

这是我的java文件，用于对话框;

public class examplefile extends DialogFragment {

public Dialog onCreateDialog(Bundle savedInstanceState) {

    final AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    LayoutInflater inf = getActivity().getLayoutInflater();
    View theDIalog = inf.inflate(R.layout.makea_transfer_confirm, null);
    builder.setView(theDIalog);

    builder.setCancelable(true);

return dialog;

}

}

现在这是你开始时获得的屏幕 - 在主要活动课程之后，但我不想分享主要活动的代码，因为我认为没有必要;

public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    final View v = inflater.inflate(R.layout.makea_transfer, container, false);


    spinner = (Spinner)v.findViewById(R.id.spinnermakeatransfer);
    ArrayAdapter adapter = ArrayAdapter.createFromResource(getActivity(), R.array.accounts,R.layout.spinner_item);
    adapter.setDropDownViewResource(R.layout.spinner_dropdown_items);
    spinner.setAdapter(adapter);
    spinner.setPrompt("Select an item");



Spinner spinner1 = (Spinner)v.findViewById(R.id.spinnermakeatransfer);
    String spinnerSelectedItem = spinner1.getSelectedItem().toString();


    TextView spinnerText = (TextView) v.findViewById(R.id.spinnerSelectedText);
    spinnerText.setText(spinnerSelectedItem);

return v;

}

现在这是makea_transfer XML;

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

<Spinner
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:id="@+id/spinnermakeatransfer"
            android:layout_marginLeft="5dp"
            android:layout_marginRight="5dp"
            android:paddingTop="5dp"
            android:spinnerMode="dialog"
            android:layout_marginTop="5dp"
            android:touchscreenBlocksFocus="false" />

</RelativeLayout>

请有人帮我解决此问题，如果您不了解或需要我提供更多详细信息，请发表评论。

这是Log Cat Click Here

Answer 1

这里：

TextView spinnerText = (TextView) v.findViewById(R.id.spinnerSelectedText);

spinnerSelectedText位于makea_transfer_confirm布局内，但试图从makea_transfer获取：

使用onCreateDialog DialogFragment的examplefile方法获取TextView：

View theDIalog = inf.inflate(R.layout.makea_transfer_confirm, null);
builder.setView(theDIalog);
// get TextView here
 TextView spinnerText = (TextView) theDIalog.findViewById(R.id.spinnerSelectedText);

要在spinnerSelectedItem中显示spinnerText值，请使用setArguments使用examplefile类传递它：

v.findViewById(R.id.maketransferReviewButton).setOnClickListener(
                                                new View.OnClickListener() { 
@Override public void onClick(View v) { 
  SampleDialog fragment = new examplefile(); 
  Bundle args = new Bundle();
  args.putString("spinnerText", spinner1.getSelectedItem().toString());
  fragment.setArguments(args);
  examplefile.show(getFragmentManager(), "make a transfer dialog"); 
 } 

});

并在onCreateDialog中使用getArguments获取String：

String strSelectedValueFromSpinner = getArguments().getString("spinnerText");
View theDIalog = inf.inflate(R.layout.makea_transfer_confirm, null);
builder.setView(theDIalog);
// get TextView here
TextView spinnerText = (TextView) theDIalog.findViewById(R.id.spinnerSelectedText);
spinnerText.setText(strSelectedValueFromSpinner);

Answer 2

你需要这样做

 spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

            @Override
            public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2, long arg3) {

                String spinnerSelectedItem = spinner.getSelectedItem().toString();
                Log.i("Selected item : ", items);
            }

            @Override
            public void onNothingSelected(AdapterView<?> arg0) {

            }

        });

和删除

Spinner spinner1 = (Spinner)v.findViewById(R.id.spinnermakeatransfer);

选择Spinner项目值

2 个答案: