Action Bar上没有显示操作按钮？ [重复]

This question already has an answer here:

这个问题在这里已有答案：

• Actionbar not shown with AppCompat 3 answers
• 操作栏未显示AppCompat 3的答案

I am following the tutorial on developer.android.com and trying to add items on action bar.

我正在关注developer.android.com上的教程并尝试在操作栏上添加项目。

Although i added all the code the search action shows as an overflow element instead of an action button element. I tried on 4" and 7" virtual devices with soft keyboard option.

虽然我添加了所有代码，但搜索操作显示为溢出元素而不是操作按钮元素。我尝试了带有软键盘选项的4“和7”虚拟设备。

Here is the

这里是

main_activity_actions.xml
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android" >
<!-- Search, should appear as action button -->
<item android:id="@+id/action_search"
    android:icon="@drawable/ic_action_search"
    android:title="@string/action_search"
    android:showAsAction="ifRoom" />
<!-- Settings, should always be in the overflow -->
<item android:id="@+id/action_settings"
    android:title="@string/action_settings"
    android:showAsAction="never" />
</menu>

Here is the MainActivity.java 's onCreateOptionsMenu method.

这是MainActivity.java的onCreateOptionsMenu方法。

 @Override
    public boolean onCreateOptionsMenu(Menu menu) {

        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main_activity_actions, menu);
        return super.onCreateOptionsMenu(menu);
    }

I want to learn what causes this problem.

我想了解导致这个问题的原因。

2 个解决方案

#1

This is because if you use the support AppCompat ActionBar library and ActionBarActivity you should create your menus in a different than the standard way of creating xml menus in ActioBarSherlock or the default ActionBar.

这是因为如果您使用支持AppCompat ActionBar库和ActionBarActivity，您应该创建不同于在ActioBarSherlock或默认ActionBar中创建xml菜单的标准方式的菜单。

So try this code :

所以试试这个代码：

<menu xmlns:android="http://schemas.android.com/apk/res/android" 
      xmlns:app="http://schemas.android.com/apk/res-auto">
      <item android:id="@+id/action_search"
          android:icon="@drawable/ic_action_search"
          android:title="@string/action_search"
          app:showAsAction="always"  />
      <item android:id="@+id/action_compose"
          android:icon="@drawable/ic_action_compose"
          android:title="@string/action_compose" 
          app:showAsAction="always"/>
</menu>

#2

Though the issue is resolved, let me post an answer with more information, may be found helpful by anyone later.

虽然问题已经解决，但是让我发布一个包含更多信息的答案，以后可能会被任何人发现。

Now, the issue is you have used android:showAsAction="ifRoom" and android:showAsAction="never", instead if you would want to make action button always visible then use android:showAsAction="always"

现在，问题是你使用了android：showAsAction =“ifRoom”和android：showAsAction =“never”，相反，如果你想让动作按钮始终可见，那么使用android：showAsAction =“always”

FYI, android:showAsAction can take either of any values:

仅供参考，android：showAsAction可以采用任何值：

android:showAsAction=["ifRoom" | "never" | "withText" | "always" | "collapseActionView"]

android：showAsAction = [“ifRoom”| “永远不会”| “withText”| “永远”| “collapseActionView”]

You can read more about Menu Resource

您可以阅读有关菜单资源的更多信息