我在Android中有一个活动,包含两个元素:

编辑文本列表视图

当“活动”启动时,EditText立即具有输入焦点(闪烁光标)。我不希望任何控件在启动时具有输入焦点。我尝试了:

EditText.setSelected(false);
EditText.setFocusable(false);

没有运气。如何说服EditText在“活动”启动时不选择自己?


当前回答

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;
}

其他回答

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"/>

它可以通过继承EditText并重写onTouchEvent来实现。

class NonFocusableEditText: EditText {

    constructor(context: Context): super(context)
    constructor(context: Context, attrs: AttributeSet?): super(context, attrs)
    constructor(context: Context, attrs: AttributeSet?, defStyleAttr: Int): super(context, attrs, defStyleAttr)

    override fun onTouchEvent(event: MotionEvent?): Boolean {
        return if (isFocusable) super.onTouchEvent(event) else false
    }
}

然后,您可以像普通的EditText一样在版面中使用它:

<com.yourpackage.NonFocusableEditText
        android:id="@+id/editText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"    
        android:hint="@string/your_hint"
        android:imeOptions="actionDone"
        android:inputType="textNoSuggestions" />

您可以通过使用请求焦点并使用键盘隐藏代码来指定其他小部件的焦点。

在Manifest文件的下面一行添加您提到的活动

android:windowSoftInputMode="stateAlwaysHidden"
/** 
 * set focus to top level window
 * disposes descendant focus 
 * disposes softInput 
 * */
public static void topLevelFocus(Context context){
    if(Activity.class.isAssignableFrom(context.getClass())){
        ViewGroup tlView = (ViewGroup) ((Activity) context).getWindow().getDecorView();
        if(tlView!=null){
            tlView.setFocusable(true);
            tlView.setFocusableInTouchMode(true);
            tlView.setDescendantFocusability(ViewGroup.FOCUS_BEFORE_DESCENDANTS);
        }
    }
}