問(wèn)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(yīng)用能夠在 SDK 10 (2.3.3) 的早期設(shè)備上運(yùn)行.我愿意放棄早期設(shè)備的操作欄功能，因?yàn)樗皇且粋€(gè)重要的功能.我已經(jīng)閱讀了有關(guān)反射、包裝類(lèi)和其他一些技術(shù)的所有內(nèi)容.我現(xiàn)在對(duì)如何完成這項(xiàng)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(méi)有將 Eclipse 中的目標(biāo)設(shè)置為 sdk 11 或更高版本，那么我引用 actionBar 的任何地方都會(huì)出現(xiàn)編譯錯(cuò)誤.如果我將目標(biāo)設(shè)置為 sdk 11 或更高版本，它會(huì)編譯但不會(huì)顯示它可以在早期設(shè)備上運(yùn)行.我一直設(shè)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(guān)于如何引用 actionBar 并讓它針對(duì)以前的 sdk 級(jí)別的見(jiàn)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(duì)可以做到這一點(diǎn).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(nèi)容(將平臺(tái)版本替換為您的應(yīng)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(guò)針對(duì) API 11 或更高版本的平臺(tái)版本，您允許 Eclipse 鏈接(編譯)本機(jī) ActionBar 類(lèi).提供較早的最低平臺(tái)版本可讓您的應(yīng)用在較早版本的 Android 上安裝(運(yùn)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(dòng)代碼應(yīng)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(lèi)僅提供靜態(tài)輔助方法來(lái)確定 SDK 的當(dāng)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(kù)，它提供了一個(gè)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(kù)將自動(dòng)使用本機(jī)操作欄可用或?qū)⒆詣?dòng)包裝自定義實(shí)現(xiàn)你的布局.這使您可以輕松地開(kāi)發(fā)具有回溯至 2.x 的每個(gè) 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.

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