EditText中並沒有實現該功能的程式碼，所以我們只能另外想方法了，具體的實現思路有兩個：一是通過監聽鍵盤的彈起，二是通過監聽EditText輸入變化然後handler傳送延遲訊息來實現。

   通過鍵盤的彈起來實現該功能比較麻煩，不考慮其他情況在佈局最簡單的情況下，程式碼實現如下：

public class MainActivity extends AppCompatActivity implements View.OnLayoutChangeListener {

    private LinearLayout layout;
@Override
protected void 
 
onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
layout = (LinearLayout) findViewById(R.id.ll);
layout.addOnLayoutChangeListener(this);
}

    @Override
public void onLayoutChange(View v, int left, int top, int right, int bottom, int 
 
oldLeft, int oldTop, int oldRight, int oldBottom) {
        Log.e("TAG", "onLayoutChange: bottom" + bottom + " ---- oldBottom" + oldBottom);
        if(bottom > oldBottom && oldBottom != 0){
            //鍵盤收起
Log.e("TAG", "onLayoutChange:  鍵盤被收起了");
//執行相關操作
}
    }
}

<activity android:name=
 
".MainActivity"
android:windowSoftInputMode="stateAlwaysHidden|adjustResize">
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/ll"
android:orientation="vertical"
tools:context="com.test.keyboardactivity.MainActivity">
    <TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World!"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
    <EditText
android:layout_width="match_parent"
android:layout_height="200dp" />
</LinearLayout>

上面描述的是佈局最簡單的情況，所以這種實現方式比較複雜，下面介紹一下通過傳送延遲訊息來實現的方法，

程式碼如下：

public class MainActivity extends AppCompatActivity implements View.OnLayoutChangeListener {

    private LinearLayout layout;
    private EditText editText;
    private static Handler handler = new Handler();
    private long TIME_LISTEN = 2000;//設定2秒的延遲
private Runnable runnable = new Runnable() {
        @Override
public void run() {
            runOnUiThread(new Runnable() {
                @Override
public void run() {
                    doSomeThing(editText.getText().toString());
}
            });
}
    };
@Override
protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
layout = (LinearLayout) findViewById(R.id.ll);
layout.addOnLayoutChangeListener(this);
editText = (EditText) findViewById(R.id.et);
editText.addTextChangedListener(new TextWatcher() {
            @Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
                handler.removeCallbacks(runnable);
}

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

            }

            @Override
public void afterTextChanged(Editable s) {
                if (!"".equals(s.toString().trim())) {
                    handler.postDelayed(runnable, TIME_LISTEN);
}
            }
        });
}

    //方法一：
@Override
public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
        Log.e("TAG", "onLayoutChange: bottom" + bottom + " ---- oldBottom" + oldBottom);
        if (bottom > oldBottom && oldBottom != 0) {
            //鍵盤收起
Log.e("TAG", "onLayoutChange:  鍵盤被收起了");
//執行相關操作
String s = editText.getText().toString();
//            if(!"".equals(s.trim())){
//                doSomeThing(s);
//            }
}
    }


    //執行操作
private void doSomeThing(String s) {
        Toast.makeText(this, s, Toast.LENGTH_SHORT).show();
}
}