java - OnEditorActionListener 中的 NullPointerException

Question

在我的 Android 项目中按 Enter 时出现 NullPointerException。我用谷歌搜索，人们遇到了同样的问题，因为他们没有设置 findViewByIt。不幸的是我明白了。发生了什么事 - 为什么我得到异常？

   @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main_page);
        textPassword = (EditText) findViewById(R.id.editText1);
        buttonLogin = (Button) findViewById(R.id.button1);
        buttonLogin.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                PrintToast(textPassword.getText().toString());
               }
             });
        textPassword.setOnEditorActionListener(new OnEditorActionListener() {

            @Override
            public boolean onEditorAction(TextView v, int actionId,
                    KeyEvent event) {
                try
                {
                if ((event.getAction() == KeyEvent.ACTION_DOWN))
                    {
                    buttonLogin.performClick();
                    }
                }
                catch ( Exception e) {
                      PrintToast(e.toString());
                }
                return false;
            }

        });



    }

布局

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/background"
    android:gravity="top"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainPage" >

    <TextView
        android:id="@+id/textView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="15dp"
        android:text="@string/PIN_label_HelloMsg"
        android:textAlignment="center"
        android:textAppearance="?android:attr/textAppearanceLarge" />

    <Button
        android:id="@+id/button1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editText1"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="35dp"
        android:text="@string/PIN_button_AcceptPIN" />

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/textView2"
        android:layout_centerHorizontal="true"
        android:text="@string/PIN_label_EnterPIN"
        android:textAppearance="?android:attr/textAppearanceMedium" />

    <EditText
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/textView1"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="30dp"
        android:ems="10"
        android:inputType="numberPassword" >

        <requestFocus />
    </EditText>

</RelativeLayout>

Answer 1

试试这个

  protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main_page);
            textPassword = (EditText) findViewById(R.id.editText1);
             buttonLogin = (Button) findViewById(R.id.button1);
            textPassword.setOnEditorActionListener(new OnEditorActionListener() {

                @Override
                public boolean onEditorAction(TextView v, int actionId,
                        KeyEvent event) {
                    try
                    {
                    if ((event.getAction() == KeyEvent.ACTION_DOWN))
                        {
                        buttonLogin.performClick();
                        }
                    }
                    catch ( Exception e) {
                          PrintToast(e.toString());
                    }
                    return false;
                }

            });

[编辑]这很好用

Button buttonLogin;
EditText textPassword ;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
textPassword = (EditText) findViewById(R.id.editText1);
 buttonLogin = (Button) findViewById(R.id.button1);
    buttonLogin.setOnClickListener(new OnClickListener() {
        public void onClick(View v) {
           Toast.makeText(MainActivity.this, textPassword.getText().toString(), Toast.LENGTH_LONG).show();
           }
         });
    textPassword.setOnEditorActionListener(new OnEditorActionListener() {

        @Override
        public boolean onEditorAction(TextView v, int actionId,
                KeyEvent event) {

            @Override
    public boolean onEditorAction(TextView v, int actionId,
            KeyEvent event) {

         if (actionId == EditorInfo.IME_ACTION_DONE) {
             // do your stuff here

            buttonLogin.performClick();
            Log.e("Called","Called OKKKKKK");
            return true;
            }

        Log.e("Called","Called");

        return false;

    }

    });



}