您可以通过创建布局宽度和高度设置为0dp的虚拟EditText，并请求对该视图进行聚焦来实现这一点。在xml布局中添加以下代码段：

<EditText
    android:id="@+id/editText0"
    android:layout_width="0dp"
    android:layout_height="0dp"
    android:hint="@string/dummy"
    android:ems="10" 
    >
     <requestFocus />
    </EditText>

在Activity的onCreate中，只需在EditText元素上添加useclearFocus（）。例如

edittext = (EditText) findViewById(R.id.edittext);
edittext.clearFocus();

如果您想将焦点转移到另一个元素，请使用requestFocus（）。例如

button = (Button) findViewById(R.id.button);
button.requestFocus();

在父布局（例如LinearLayout或ConstraintLayout）中添加标签android:focusableInTouchMode=“true”和android:focusable=“true”将解决该问题。

<!-- Dummy item to prevent AutoCompleteTextView from receiving focus -->
<LinearLayout
    android:focusable="true" 
    android:focusableInTouchMode="true"
    android:layout_width="0px" 
    android:layout_height="0px"/>

<!-- :nextFocusUp and :nextFocusLeft have been set to the id of this component
to prevent the dummy from receiving focus again -->
<AutoCompleteTextView android:id="@+id/autotext"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content"
    android:nextFocusUp="@id/autotext" 
    android:nextFocusLeft="@id/autotext"/>

请尝试clearFocus（）而不是setSelected（false）。Android中的每个视图都具有可聚焦性和可选择性，我认为您只需要清除焦点。

由于我不喜欢用与功能相关的东西来污染XML，所以我创建了这个方法，它“透明地”从第一个可聚焦视图中窃取焦点，然后确保在必要时删除它自己！

public static View preventInitialFocus(final Activity activity)
{
    final ViewGroup content = (ViewGroup)activity.findViewById(android.R.id.content);
    final View root = content.getChildAt(0);
    if (root == null) return null;
    final View focusDummy = new View(activity);
    final View.OnFocusChangeListener onFocusChangeListener = new View.OnFocusChangeListener()
    {
        @Override
        public void onFocusChange(View view, boolean b)
        {
            view.setOnFocusChangeListener(null);
            content.removeView(focusDummy);
        }
    };
    focusDummy.setFocusable(true);
    focusDummy.setFocusableInTouchMode(true);
    content.addView(focusDummy, 0, new LinearLayout.LayoutParams(0, 0));
    if (root instanceof ViewGroup)
    {
        final ViewGroup _root = (ViewGroup)root;
        for (int i = 1, children = _root.getChildCount(); i < children; i++)
        {
            final View child = _root.getChildAt(i);
            if (child.isFocusable() || child.isFocusableInTouchMode())
            {
                child.setOnFocusChangeListener(onFocusChangeListener);
                break;
            }
        }
    }
    else if (root.isFocusable() || root.isFocusableInTouchMode())
        root.setOnFocusChangeListener(onFocusChangeListener);

    return focusDummy;
}

问题似乎来自我只能在布局的XML形式中看到的属性。

确保在EditText XML标记中删除声明末尾的此行：

<requestFocus />

这应该是这样的：

<EditText
   android:id="@+id/emailField"
   android:layout_width="fill_parent"
   android:layout_height="wrap_content"
   android:inputType="textEmailAddress">

   //<requestFocus /> /* <-- without this line */
</EditText>