java - How to change layout by clicking items of menu?

Question

I'm trying to enable users to change layout of my apps.

This is my XML:

<menu xmlns:android="http://schemas.android.com/apk/res/android" >

<item
    android:id="@+id/menuTheme"
    android:orderInCategory="1"
    android:showAsAction="never"
    android:title="Theme">
    <menu>
        <item
            android:id="@+id/themeBlack"
            android:title="Black" />
        <item
            android:id="@+id/themeWhite"
            android:title="White" />
    </menu>
</item>

<item
    android:id="@+id/menuAbout"
    android:orderInCategory="1"
    android:showAsAction="never"
    android:title="About" />

Here are the screenshots from my emulator: This is my menu.

After clicking the item Theme under the menu, this submenu will appear.

Lets say i wish to add a white layout, where and how should i add codes?I have a XML file named themewhite.XML in the res/layout folder. I tried to add a switch in the item theme but it doesn't seemed to be correct.

This is my code:

    @Override
public boolean onOptionsItemSelected(MenuItem item)
{
    switch(item.getItemId())
    {
        case R.id.menuTheme:
        {
            switch(item.getItemId())
            {
                case R.id.themeWhite;
                {
                    setContentView(R.layout.themewhite);
                }
            }
            break;
        }
        case R.id.menuAbout:
        {
            break;
        }
    }
    return super.onOptionsItemSelected(item);
}

Answer 1

我猜你不想设置新的布局，你只想改变现有的可视化。

如果是这样，您应该使用您的活动主题。首先，您需要使用样式中的值创建主题（白色等）和贴花视图属性。然后在你的听众中点击其中一项后，你应该通过调用来改变你的主题
getContext().setTheme(resid)

这里有一篇关于主题的好文章http://www.androidengineer.com/2010/06/using-themes-in-android-applications.html