如何加载布局并将其添加到Android中的另一个布局？

Question

我想加载布局XML文件并将布局广告到当前内容视图。

所以，如果我在这里得到这个布局：

如果我点击硬件搜索按钮，那么我想在屏幕顶部显示一个搜索栏，如下所示：

基于this answer，我尝试过这样的事情：

MainActivity.java

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    LayoutInflater inflater = (LayoutInflater) getBaseContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View v = inflater.inflate(R.layout.search_bar, null);

    ViewGroup layout = (ViewGroup) findViewById(R.id.layout_main);
    layout.addView(v);
}

搜索栏是名为 search_bar.xml 的布局文件。 R.layout.activity_main是主要活动。 R.id.layout_main是RelativeLayout的ID，它是 activity_main 中的容器。

但是我得到了一个错误导致类。

如何加载布局并将其添加到当前加载的布局？

Answer 1

我没有看到您的代码存在明显问题。正如评论中提到的，请在此处发布日志。

我可以建议另一种方法吗？您可以包含搜索栏（在主要布局中或使用include标记）并将其可见性设置为GONE，直到您需要显示它为止。

Answer 2

我做了一些研究，并结合了几个提示解决方案 首先，我使用了LayoutInflater.from(Context)而不是Context.LAYOUT_INFLATER_SERVICE（虽然这似乎不是问题）。其次，我使用了onSearchRequest()方法。

结果如下：

/**
 * Whether the search bar is visible or not.
 */
private boolean searchState = false;

/**
 * The View loaded from the search_bar.xml layout.
 */
private View searchView;

/**
 * This method is overridden from the Activity class, enabling you to define events when the hardware search button is pressed.
 *
 * @return Returns true if search launched, and false if activity blocks it.
 */
public boolean onSearchRequested() {
    // Toggle the search state.
    this.searchState = !this.searchState;
    // Find the main layout
    ViewGroup viewGroup = (ViewGroup) findViewById(R.id.layout_main);
    // If the search button is pressed and the state has been toggled on:
    if (this.searchState) {
        LayoutInflater factory = LayoutInflater.from(this.activity);
        // Load the search_bar.xml layout file and save it to a class attribute for later use.
        this.searchView = factory.inflate(R.layout.search_bar, null);
        // Add the search_bar to the main layout (on position 0, so it will be at the top of the screen if the viewGroup is a vertically oriented LinearLayout).
        viewGroup.addView(this.searchView, 0);
    }
    // Else, if the search state is false, we assume that it was on and the search_bar was loaded. Now we remove the search_bar from the main view.
    else {
        viewGroup.removeView(this.searchView);
    }
    return false;
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
}