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!");
                    }
           }
          });

硬件键盘总是产生输入事件，但是软件键盘在单个的lineedittext中返回不同的actionid和null。每当用户在已设置此侦听器的EditText中按下enter键时，此代码就会响应，而不管EditText或键盘类型是什么。

import android.view.inputmethod.EditorInfo;
import android.view.KeyEvent;
import android.widget.TextView.OnEditorActionListener;

listener=new TextView.OnEditorActionListener() {
  @Override
  public boolean onEditorAction(TextView view, int actionId, KeyEvent event) {
    if (event==null) {
      if (actionId==EditorInfo.IME_ACTION_DONE);
      // Capture soft enters in a singleLine EditText that is the last EditText.
      else if (actionId==EditorInfo.IME_ACTION_NEXT);
      // Capture soft enters in other singleLine EditTexts
      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.
      else  return true;   // We consume the event when the key is released.  
    }
    else  return false; 
    // We let the system handle it when the listener
    // is triggered by something that wasn't an enter.


    // Code from this point on will execute whenever the user
    // presses enter in an attached view, regardless of position, 
    // keyboard, or singleLine status.

    if (view==multiLineEditText)  multiLineEditText.setText("You pressed enter");
    if (view==singleLineEditText)  singleLineEditText.setText("You pressed next");
    if (view==lastSingleLineEditText)  lastSingleLineEditText.setText("You pressed done");
    return true;   // Consume the event
  }
};

The default appearance of the enter key in singleLine=false gives a bent arrow enter keypad. When singleLine=true in the last EditText the key says DONE, and on the EditTexts before it it says NEXT. By default, this behavior is consistent across all vanilla, android, and google emulators. The scrollHorizontal attribute doesn't make any difference. The null test is important because the response of phones to soft enters is left to the manufacturer and even in the emulators, the vanilla Level 16 emulators respond to long soft enters in multi-line and scrollHorizontal EditTexts with an actionId of NEXT and a null for the event.

我想知道是否有办法 处理用户按Enter键时 输入EditText之类的 onSubmit HTML事件。

是的。

也在想有没有办法 操作虚拟键盘 就像“完成”按钮一样 标记其他东西(例如 “Go”)并执行某个动作 当点击(再次，像onSubmit)。

也没错。

你会想看看android:imeActionId和android:imeOptions属性，加上setOnEditorActionListener()方法，所有的TextView。

要将“Done”按钮的文本更改为自定义字符串，请使用:

mEditText.setImeActionLabel("Custom text", KeyEvent.KEYCODE_ENTER);

A dependable way to respond to an <enter> in an EditText is with a TextWatcher, a LocalBroadcastManager, and a BroadcastReceiver. You need to add the v4 support library to use the LocalBroadcastManager. I use the tutorial at vogella.com: 7.3 "Local broadcast events with LocalBroadcastManager" because of its complete concise code Example. In onTextChanged before is the index of the end of the change before the change>;minus start. When in the TextWatcher the UI thread is busy updating editText's editable, so we send an Intent to wake up the BroadcastReceiver when the UI thread is done updating editText.

import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.text.Editable;
//in onCreate:
editText.addTextChangedListener(new TextWatcher() {
  public void onTextChanged
  (CharSequence s, int start, int before, int count) {
    //check if exactly one char was added and it was an <enter>
    if (before==0 && count==1 && s.charAt(start)=='\n') {
    Intent intent=new Intent("enter")
    Integer startInteger=new Integer(start);
    intent.putExtra("Start", startInteger.toString()); // Add data
    mySendBroadcast(intent);
//in the BroadcastReceiver's onReceive:
int start=Integer.parseInt(intent.getStringExtra("Start"));
editText.getText().replace(start, start+1,""); //remove the <enter>
//respond to the <enter> here

我通过扩展新的MaterialAlertDialogBuilder创建了一个辅助类

使用

new InputPopupBuilder(context)
        .setInput(R.string.send, 
                R.string.enter_your_message, 
                text -> sendFeedback(text, activity))
        .setTitle(R.string.contact_us)
        .show();

Code

public class InputPopupBuilder extends MaterialAlertDialogBuilder {

    private final Context context;
    private final AppCompatEditText input;

    public InputPopupBuilder(Context context) {
        super(context);
        this.context = context;
        input = new AppCompatEditText(context);
        input.setInputType(InputType.TYPE_CLASS_TEXT);
        setView(input);
    }

    public InputPopupBuilder setInput(int actionLabel, int hint, Callback callback) {
        input.setHint(hint);
        input.setImeActionLabel(context.getString(actionLabel), KeyEvent.KEYCODE_ENTER);
        input.setOnEditorActionListener((TextView.OnEditorActionListener) (v, actionId, event) -> {
            if (actionId == EditorInfo.IME_NULL
                    && event.getAction() == KeyEvent.ACTION_DOWN) {
                Editable text = input.getText();
                if (text != null) {
                    callback.onClick(text.toString());
                    return true;
                }
            }
            return false;
        });

        setPositiveButton(actionLabel, (dialog, which) -> {
            Editable text = input.getText();
            if (text != null) {
                callback.onClick(text.toString());
            }
        });

        return this;
    }

    public InputPopupBuilder setText(String text){
        input.setText(text);
        return this;
    }

    public InputPopupBuilder setInputType(int inputType){
        input.setInputType(inputType);
        return this;
    }

    public interface Callback {
        void onClick(String text);
    }
}

需要

implementation 'com.google.android.material:material:1.3.0-alpha04'

本页详细描述了如何做到这一点。

https://developer.android.com/training/keyboard-input/style.html

设置android:imeOptions，然后检查onEditorAction中的actionId。因此，如果你设置imeOptions为“actionDone”，那么你会检查“actionId == EditorInfo”。onEditorAction中的IME_ACTION_DONE `。另外，确保设置android:inputType。

如果使用材质设计，将代码放在TextInputEditText中。

下面是上面链接的例子中的EditText:

<EditText
    android:id="@+id/search"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:hint="@string/search_hint"
    android:inputType="text"
    android:imeOptions="actionSend" />

您还可以使用setImeOptions(int)函数以编程方式设置此选项。下面是上面链接的例子中的OnEditorActionListener:

EditText editText = (EditText) findViewById(R.id.search);
editText.setOnEditorActionListener(new OnEditorActionListener() {
    @Override
    public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
        boolean handled = false;
        if (actionId == EditorInfo.IME_ACTION_SEND) {
            sendMessage();
            handled = true;
        }
        return handled;
    }
});