我想知道是否有一种方法来处理用户在输入EditText时按下Enter,就像onSubmit HTML事件。

还想知道是否有一种方法来操纵虚拟键盘,以这样的方式,“完成”按钮被标记为其他的东西(例如“Go”),并在单击时执行特定的动作(再次,像onSubmit)。


当前回答

如果使用DataBinding,请参见https://stackoverflow.com/a/52902266/2914140和https://stackoverflow.com/a/67933283/2914140。

Bindings.kt:

@BindingAdapter("onEditorEnterAction")
fun EditText.onEditorEnterAction(callback: OnActionListener?) {
    if (callback == null) setOnEditorActionListener(null)
    else setOnEditorActionListener { v, actionId, event ->
        val imeAction = when (actionId) {
            EditorInfo.IME_ACTION_DONE,
            EditorInfo.IME_ACTION_SEND,
            EditorInfo.IME_ACTION_GO -> true
            else -> false
        }

        val keydownEvent = event?.keyCode == KeyEvent.KEYCODE_ENTER 
            && event.action == KeyEvent.ACTION_DOWN

        if (imeAction or keydownEvent) {
            callback.enterPressed()
            return@setOnEditorActionListener true
        }
        return@setOnEditorActionListener false
    }
}

interface OnActionListener {
    fun enterPressed()
}

layout.xml:

<data>
    <variable
        name="viewModel"
        type="YourViewModel" />
</data>    

<EditText
    android:imeOptions="actionDone|actionSend|actionGo"
    android:singleLine="true"
    android:text="@={viewModel.message}"
    app:onEditorEnterAction="@{() -> viewModel.send()}" />

其他回答

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'

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;
        }
    };
}

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;
                }
            }
        });

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。

你应该这样做。它也隐藏在Android开发者的样例代码“蓝牙聊天”中。用你自己的变量和方法替换“example”的粗体部分。

首先,把你需要的东西导入到主Activity中,你想让返回按钮做一些特殊的事情:

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

现在,创建一个类型为TextView的变量。OnEditorActionListener作为返回键(这里我使用exampleListener);

TextView.OnEditorActionListener exampleListener = new TextView.OnEditorActionListener(){

然后,您需要告诉侦听器当按下返回按钮时该做什么。它需要知道我们谈论的EditText是什么(这里我使用exampleView),然后它需要知道当按下Enter键时要做什么(这里是example_confirm())。如果这是活动中最后一个或唯一一个EditText,它应该做与提交(或确定,确认,发送,保存等)按钮的onClick方法相同的事情。

public boolean onEditorAction(TextView exampleView, int actionId, KeyEvent event) {
   if (actionId == EditorInfo.IME_NULL  
      && event.getAction() == KeyEvent.ACTION_DOWN) { 
      example_confirm();//match this behavior to your 'Send' (or Confirm) button
   }
   return true;
}

最后,设置监听器(很可能在你的onCreate方法中);

exampleView.setOnEditorActionListener(exampleListener);