你可以使用这段代码，使用你的主布局Id而不是"mainRelativeLayout"

//hide Soft keyboard on click outside  the input text
    findViewById(R.id.mainRelativeLayout).setOnClickListener(new 
View.OnClickListener() {
        @Override
        public void onClick(View v) {
            InputMethodManager im = (InputMethodManager) 
getSystemService(INPUT_METHOD_SERVICE);
            im.hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), 
0);
        }

    });

使用OnFocusChangeListener。

例如:

editText.setOnFocusChangeListener(new View.OnFocusChangeListener() {
    @Override
    public void onFocusChange(View v, boolean hasFocus) {
        if (!hasFocus) {
            hideKeyboard();
        }
    }
});

更新:你也可以覆盖onTouchEvent()在你的活动和检查触摸的坐标。如果坐标在EditText之外，则隐藏键盘。

对于这个简单的要求，我发现公认的答案有点复杂。以下是对我有效的方法，没有任何故障。

findViewById(R.id.mainLayout).setOnTouchListener(new View.OnTouchListener() {
        @Override
        public boolean onTouch(View view, MotionEvent motionEvent) {
            InputMethodManager imm = (InputMethodManager) getSystemService(INPUT_METHOD_SERVICE);
            imm.hideSoftInputFromWindow(getCurrentFocus().getWindowToken(), 0);
            return false;
        }
    });

我稍微修改了一下@ navneth -g的答案，增加了null活动焦点处理，避免了创建OnTouchListener的多个实例，键盘隐藏时删除焦点，屏幕滚动时删除隐藏键盘，在小设备上方便。

//In general, the view parameter is root layout
fun Activity.hideKeyboardOnClickOutsideEditText(view: View) {
    // Set up touch listener for non-text box views to hide keyboard.
    var previousAction = 0
    val onTouchListener = View.OnTouchListener { v, event ->
        if (currentFocus != null
            && event.action != MotionEvent.ACTION_DOWN
            && event.action != MotionEvent.ACTION_MOVE
            && previousAction != MotionEvent.ACTION_MOVE
        ) {
            currentFocus?.clearFocus()
            v?.hideKeyboard()
        }
        previousAction = event.action
        false
    }

    if (view !is EditText) {
        view.setOnTouchListener(onTouchListener)
    }

    //If a layout container, iterate over children and seed recursion.
    if (view is ViewGroup) {
        for (i in 0 until view.childCount) {
            val innerView = view.getChildAt(i)
            hideKeyboardOnClickOutsideEditText(innerView)
        }
    }
}
   
//in root layout.xml
android:clickable="true"
android:focusable="true"
android:focusableInTouchMode="true"

另一个想法是覆盖onInterceptTouchEvent方法在根视图为您的活动。

触摸事件从屏幕上最前面的视图(触摸事件发生的地方)沿着调用onTouch方法的视图堆栈向下移动，直到任何视图返回true，表明触摸事件被消费。由于许多视图默认使用触摸事件(例如，EditText或TextView的情况)，事件不会到达活动的根视图onTouch方法。

But, before do this traversal, the touch event travels another path, going from the root view down the view tree until it gets to the front most view. This traversal is done by calling onInterceptTouchEvent. If the method returns true, it intercepts the event... nahhh, but that is a little bit trick, I don't think you want to do that nor to know the details. What you need to know is that you can override this method on the root view for your Activity, and put there the code to hide the keyboard when necessary.

这是对fje的答案稍加修改的版本，这个答案基本上非常有效。

这个版本使用ACTION_DOWN，所以执行滚动动作也会关闭键盘。 它也不会传播事件，除非您单击另一个EditText。这意味着点击EditText以外的任何地方，即使是在另一个可点击的地方，也只是关闭键盘。

@Override
public boolean dispatchTouchEvent(MotionEvent ev)
{
    if(ev.getAction() == MotionEvent.ACTION_DOWN)
    {
        final View view = getCurrentFocus();

        if(view != null)
        {
            final View viewTmp = getCurrentFocus();
            final View viewNew = viewTmp != null ? viewTmp : view;

            if(viewNew.equals(view))
            {
                final Rect rect = new Rect();
                final int[] coordinates = new int[2];

                view.getLocationOnScreen(coordinates);

                rect.set(coordinates[0], coordinates[1], coordinates[0] + view.getWidth(), coordinates[1] + view.getHeight());

                final int x = (int) ev.getX();
                final int y = (int) ev.getY();

                if(rect.contains(x, y))
                {
                    super.dispatchTouchEvent(ev);
                    return true;
                }
            }
            else if(viewNew instanceof EditText || viewNew instanceof CustomEditText)
            {
                super.dispatchTouchEvent(ev);
                return true;
            }

            final InputMethodManager inputMethodManager = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);

            inputMethodManager.hideSoftInputFromWindow(viewNew.getWindowToken(), 0);

            viewNew.clearFocus();

            return true;
        }
    }
    return super.dispatchTouchEvent(ev);
}