这将在用户按下返回键时为您提供一个可调用的函数。

fun EditText.setLineBreakListener(onLineBreak: () -> Unit) {
    val lineBreak = "\n"
    doOnTextChanged { text, _, _, _ ->
        val currentText = text.toString()

        // Check if text contains a line break
        if (currentText.contains(lineBreak)) {

            // Uncommenting the lines below will remove the line break from the string
            // and set the cursor back to the end of the line

            // val cleanedString = currentText.replace(lineBreak, "")
            // setText(cleanedString)
            // setSelection(cleanedString.length)

            onLineBreak()
        }
    }
}

使用

editText.setLineBreakListener {
    doSomething()
}

检测回车键被按下的最简单的方法是:

mPasswordField.setOnEditorActionListener(new TextView.OnEditorActionListener() {
            @Override
            public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
                if (event!= null) {   // KeyEvent: If triggered by an enter key, this is the event; otherwise, this is null.
                    signIn(mEmailField.getText().toString(), mPasswordField.getText().toString());
                    return true;
                } else {
                    return false;
                }
            }
        });

完美的工作

public class MainActivity extends AppCompatActivity {  
TextView t;
Button b;
EditText e;

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

    b = (Button) findViewById(R.id.b);
    e = (EditText) findViewById(R.id.e);

    e.addTextChangedListener(new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {

            if (before == 0 && count == 1 && s.charAt(start) == '\n') {

                b.performClick();
                e.getText().replace(start, start + 1, ""); //remove the <enter>
            }

        }
        @Override
        public void beforeTextChanged(CharSequence s, int start, int count, int after) {}
        @Override
        public void afterTextChanged(Editable s) {}
    });

    b.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            b.setText("ok");

        }
    });
}

}

完美的工作

final EditText edittext = (EditText) findViewById(R.id.edittext);
edittext.setOnKeyListener(new OnKeyListener() {
    public boolean onKey(View v, int keyCode, KeyEvent event) {
        // If the event is a key-down event on the "enter" button
        if ((event.getAction() == KeyEvent.ACTION_DOWN) &&
            (keyCode == KeyEvent.KEYCODE_ENTER)) {
          // Perform action on key press
          Toast.makeText(HelloFormStuff.this, edittext.getText(), Toast.LENGTH_SHORT).show();
          return true;
        }
        return false;
    }
});

文本字段上的InputType必须是文本，以便CommonsWare所说的工作。刚刚尝试了所有这些，在试验之前没有inputType，没有任何工作，进入一直注册为软进入。在inputType = text之后，包括setImeLabel在内的所有东西都工作了。

示例:android:inputType="text"

     password.setOnEditorActionListener(new TextView.OnEditorActionListener() {
        public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
            if(event != null && event.getKeyCode() == KeyEvent.KEYCODE_ENTER && event.getAction() == KeyEvent.ACTION_DOWN) {
                InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
                imm.toggleSoftInput(InputMethodManager.SHOW_IMPLICIT, 0);
                submit.performClick();
                return true;
            }
            return false;
        }
    });

对我来说很好 另外隐藏键盘