問題描述

我想使用 SDK 11 中包含的操作欄功能.但是，我還希望該應用能夠在 SDK 10 (2.3.3) 的早期設備上運行.我愿意放棄早期設備的操作欄功能，因為它不是一個重要的功能.我已經閱讀了有關反射、包裝類和其他一些技術的所有內容.我現在對如何完成這項工作感到困惑.我正在使用 Eclipse.

I want to use the actionbar feature included in SDK 11. However I also want the app to run on earlier devices from SDK 10 (2.3.3). I am willing to give up the actionbar feature for the earlier devices as it is not an important feature. I have done all the reading about reflection, wrapper class and some other techniques. I am now stumped on exactly how to make this work. I am using Eclipse.

如果我沒有將 Eclipse 中的目標設置為 sdk 11 或更高版本，那么我引用 actionBar 的任何地方都會出現編譯錯誤.如果我將目標設置為 sdk 11 或更高版本，它會編譯但不會顯示它可以在早期設備上運行.我一直設置 android:minSdkVersion=10.

If I don't set the target in Eclipse to sdk 11 or greater, then any place I have a reference to actionBar gives a compile error. If I put the target to sdk 11 or greater it compiles but won't show that it can run on earlier devices. I have android:minSdkVersion=10 set all the time.

有人能給我一些關于如何引用 actionBar 并讓它針對以前的 sdk 級別的見解嗎?提前致謝.

Can someone give me some insight on how to make the references to actionBar and yet get it to target a previous sdk level? Thanks in advance.

推薦答案

是的！你絕對可以做到這一點.嘗試遵循下面概述的模式.

Yes! You can definitely do this. Try following the pattern outlined below.

在您的 AndroidManifest.xml 文件中聲明以下內容(將平臺版本替換為您的應用所需的任何版本):

In your AndroidManifest.xml file declare the following (replacing the platform versions with whatever your app requires):

<!-- Build Target -->
<uses-sdk android:targetSdkVersion="14" android:minSdkVersion="7" />

通過針對 API 11 或更高版本的平臺版本，您允許 Eclipse 鏈接(編譯)本機 ActionBar 類.提供較早的最低平臺版本可讓您的應用在較早版本的 Android 上安裝(運行).

By targeting a platform version of API 11 or higher, you are allowing Eclipse to link (compile) against the native ActionBar classes. Providing an earlier minimum platform version allows your app to be installed (run) on older versions of Android.

您的活動代碼應如下所示:

Your Activity code should then look something like this:

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    if (CompatibilityManager.isHoneycomb()) {
        final ActionBar actionBar = getActionBar();
        actionBar.setDisplayShowHomeEnabled(true);
        // ...
    } else {
        // The ActionBar is unavailable!
        // ...
    }
}

CompatibilityManager.java 類僅提供靜態輔助方法來確定 SDK 的當前版本:

Where the CompatibilityManager.java class simply provides static helper methods for determining the current version of the SDK:

public class CompatibilityManager {
    public static final String KINDLE_FIRE_MODEL = "Kindle Fire";

    /**
     * Get the current Android API level.
     */
    public static int getSdkVersion() {
        return android.os.Build.VERSION.SDK_INT;
    }

    /**
     * Determine if the device is running API level 11 or higher.
     */
    public static boolean isHoneycomb() {
        return getSdkVersion() >= Build.VERSION_CODES.HONEYCOMB;
    }

    /**
     * Determine if the device is running API level 14 or higher.
     */
    public static boolean isIceCreamSandwich() {
        return getSdkVersion() >= Build.VERSION_CODES.ICE_CREAM_SANDWICH;
    }

    /**
     * Determine if the current device is a first generation Kindle Fire.
     * @return true if the device model is equal to "Kindle Fire", false if otherwise.
     */
    public static boolean isKindleFire() {
        return Build.MODEL.equals(KINDLE_FIRE_MODEL);
    }
}

您還可以考慮利用 ActionBarSherlock 庫，它提供了一個兼容的 ActionBar API，可以追溯到 Android 2.x:

You might also consider leveraging the ActionBarSherlock library, which provides a compatible ActionBar API all the way back to Android 2.x:

庫將自動使用本機操作欄可用或將自動包裝自定義實現你的布局.這使您可以輕松地開發具有回溯至 2.x 的每個 Android 版本的操作欄.

The library will automatically use the native action bar when available or will automatically wrap a custom implementation around your layouts. This allows you to easily develop an application with an action bar for every version of Android back through 2.x.

玩得開心！

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