android - 当我单击 "App name"按钮时，"TRANSLATE"不断停止。

Question

因此，我尝试使用 EditText 获取用户输入，并在单击“翻译”按钮后将文本显示到 TextView 中。下面是我的类，其中包含源代码。请帮忙!在使用 Google Cloud API 提取要翻译的内容之前，我需要能够成功提取用户的输入，这就是为什么我现在只是尝试通过 TextView 提取并显示它，但它似乎不起作用现在...

public class Translator extends Fragment {

    public Spinner spinner1, spinner2;
    TextView textView;
    EditText texttotranslate;


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.translator, container, false);

    getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_NOTHING);

    ImageButton switchbutton;
    Button translatebutton;

    //Both Spinner's Languages
    String [] Languages =
            {"English","Malay","Chinese","Korean","Japanese","Arabic","Indonesian","Spanish"};

    //LanguageFromSpinner
    spinner1 = (Spinner) view.findViewById(R.id.languagefromspinner);
    ArrayAdapter<String> adapter1 = new ArrayAdapter<String>(this.getActivity(), android.R.layout.simple_spinner_item, Languages);
    adapter1.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
    spinner1.setAdapter(adapter1);

    //LanguageToSpinner
    spinner2 = (Spinner) view.findViewById(R.id.languagetospinner);
    ArrayAdapter<String> adapter2 = new ArrayAdapter<String>(this.getActivity(), android.R.layout.simple_spinner_item, Languages);
    adapter2.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
    spinner2.setAdapter(adapter2);

    //Button to switch language between spinner1 & spinner2
    switchbutton = (ImageButton) view.findViewById(R.id.languageswitchButton);
    switchbutton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            int spinner1Index = spinner1.getSelectedItemPosition();

            spinner1.setSelection(spinner2.getSelectedItemPosition());
            spinner2.setSelection(spinner1Index );
        }
    });

    //Button to translate
    translatebutton = (Button) view.findViewById(R.id.translatebutton);

    translatebutton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            textView = (TextView) getView().findViewById(R.id.translatedtext);
            texttotranslate = (EditText) v.findViewById(R.id.translatetextinput);
            String textstorage = texttotranslate.getText().toString();
            textView.setText(textstorage);
        }
    });


 --------- beginning of crash
09-26 10:43:59.824 6294-6294/project.myapplication E/AndroidRuntime: FATAL 
EXCEPTION: main
    Process: project.myapplication, PID: 6294
    java.lang.NullPointerException: Attempt to invoke virtual method 'android.text.Editable android.widget.EditText.getText()' on a null object reference
    at project.myapplication.Translator$2.onClick(Translator.java:90)
    at android.view.View.performClick(View.java:6294)
    at android.view.View$PerformClick.run(View.java:24770)
    at android.os.Handler.handleCallback(Handler.java:790)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:164)
    at android.app.ActivityThread.main(ActivityThread.java:6494)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)

Answer 1

堆栈跟踪表明，当您尝试调用其 getText() 方法时，您的 EditText 为 null。

在事件处理程序中，您调用:

texttotranslate = (EditText) v.findViewById(R.id.translatetextinput);

在此上下文中，v 是触发 click 事件(也称为按钮)的 View 。您正在尝试在按钮内部查找 ID 为 translatetextinput 的 View 。

您可能想写:

texttotranslate = (EditText) getView().findViewById(R.id.translatetextinput);

它将在整个 fragment 的 View 层次结构中查找 View 。