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;
        }
    });

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

添加这些依赖项，应该可以工作:

import android.view.KeyEvent;
import android.view.View;
import android.widget.EditText;

在xml中，将imeOptions属性添加到editText中

<EditText
    android:id="@+id/edittext_additem"
    ...
    android:imeOptions="actionDone"
    />

然后，在Java代码中，将OnEditorActionListener添加到相同的EditText中

mAddItemEditText.setOnEditorActionListener(new TextView.OnEditorActionListener() {
        @Override
        public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
            if(actionId == EditorInfo.IME_ACTION_DONE){
                //do stuff
                return true;
            }
            return false;
        }
    });

下面是解释 imeOptions=actionDone将“actionDone”分配给EnterKey。键盘上的EnterKey将从“Enter”变为“Done”。因此，当按下回车键时，它将触发这个动作，因此您将处理它。

下面是一个简单的静态函数，您可以将它扔到Utils或keyboard类中，当用户敲击硬件或软件键盘上的返回键时，它将执行代码。这是@earlcasper精彩回答的修改版

 /**
 * Return a TextView.OnEditorActionListener that will execute code when an enter is pressed on
 * the keyboard.<br>
 * <code>
 *     myTextView.setOnEditorActionListener(Keyboards.onEnterEditorActionListener(new Runnable()->{
 *         Toast.makeText(context,"Enter Pressed",Toast.LENGTH_SHORT).show();
 *     }));
 * </code>
 * @param doOnEnter A Runnable for what to do when the user hits enter
 * @return the TextView.OnEditorActionListener
 */
public static TextView.OnEditorActionListener onEnterEditorActionListener(final Runnable doOnEnter){
    return (__, actionId, event) -> {
        if (event==null) {
            if (actionId == EditorInfo.IME_ACTION_DONE) {
                // Capture soft enters in a singleLine EditText that is the last EditText.
                doOnEnter.run();
                return true;
            } else if (actionId==EditorInfo.IME_ACTION_NEXT) {
                // Capture soft enters in other singleLine EditTexts
                doOnEnter.run();
                return true;
            } else {
                return false;  // Let system handle all other null KeyEvents
            }
        } else if (actionId==EditorInfo.IME_NULL) {
            // Capture most soft enters in multi-line EditTexts and all hard enters.
            // They supply a zero actionId and a valid KeyEvent rather than
            // a non-zero actionId and a null event like the previous cases.
            if (event.getAction()==KeyEvent.ACTION_DOWN) {
                // We capture the event when key is first pressed.
                return true;
            } else {
                doOnEnter.run();
                return true;   // We consume the event when the key is released.
            }
        } else {
            // We let the system handle it when the listener
            // is triggered by something that wasn't an enter.
            return false;
        }
    };
}

这应该可以

input.addTextChangedListener(new TextWatcher() {

           @Override
           public void afterTextChanged(Editable s) {}

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

           @Override    
           public void onTextChanged(CharSequence s, int start,
             int before, int count) {
               if( -1 != input.getText().toString().indexOf( "\n" ) ){
                   input.setText("Enter was pressed!");
                    }
           }
          });