Question

我刚试过这段代码：

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.action_settings:
            return true;
        case R.id.action_search:
            MenuItemCompat.setOnActionExpandListener(item.findItem(R.id.action_search),
                    new MenuItemCompat.OnActionExpandListener() {
                @Override
                public boolean onMenuItemActionExpand(MenuItem item) {
                    System.out.println("expand");
                    return true;
                }

                @Override
                public boolean onMenuItemActionCollapse(MenuItem item) {
                    System.out.println("collapse");
                    return true;
                }
            });
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

但是它显示了一个错误，说：

无法解析方法＆＃34; findItem（int）＆＃34;

我检查了android developer，该方法似乎与我使用它的方式一样有效。有谁知道它为什么不起作用？感谢

Answer 1

文档称它应该被称为菜单

item.findItem(R.id.action_search) // Here item is MenuItem not Menu

Answer 2

试试这种方式

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.action_settings:
            return true;
        case R.id.action_search:
            MenuItemCompat.setOnActionExpandListener(item,
                    new MenuItemCompat.OnActionExpandListener() {
                @Override
                public boolean onMenuItemActionExpand(MenuItem item) {
                    System.out.println("expand");
                    return true;
                }

                @Override
                public boolean onMenuItemActionCollapse(MenuItem item) {
                    System.out.println("collapse");
                    return true;
                }
            });
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

无法解析方法＆＃34; findItem（int）＆＃34;

2 个答案: