How to Android? Step1:Tools and SDK

We can use the Eclipse IDE as our environment for developing Android applications, and install a custom plugin called Android Development Tools (ADT), which adds integrated support for Android projects and tools. The ADT plugin includes a variety of powerful extensions that make creating, running, and debugging Android applications faster and easier.

To download and install the ADT plugin, set up an Eclipse remote update site as described in the steps below.

1. Start Eclipse, then select Help > Software Updates > Find and Install....
2. In the dialog that appears, select Search for new features to install and press Next.
3. Press New Remote Site.
4. In the resulting dialog box, enter a name for the remote site (e.g. Android Plugin) and enter this as its URL:

   https://dl-ssl.google.com/android/eclipse/

   Press OK.
5. You should now see the new site added to the search list (and checked). Press Finish.
6. In the subsequent Search Results dialog box, select the checkbox for Android Plugin > Eclipse Integration > Android Development Tools and press Next.
7. Read the license agreement and then select Accept terms of the license agreement, if appropriate. Press Next.
8. Press Finish.
9. The ADT plugin is not signed; you can accept the installation anyway by pressing Install All.
10. Restart Eclipse.
11. After restart, update your Eclipse preferences to point to the SDK directory:
1. Select Window > Preferences... to open the Preferences panel. (Mac OS X: Eclipse > Preferences)
2. Select Android from the left panel.
3. For the SDK Location in the main panel, press Browse... and locate the SDK directory.
4. Press Apply, then OK.

Last step, Let's download Android SDK.

所謂工欲善其事必先利其器，而Android主要是已Java-based進行開發，所以在此建議你使用Eclipse IDE來開發Android。你可以在下方連結進行下載：
Eclipse Downloads Home

當你安裝Eclipse後，然後再安裝Android Development Tools (ADT) 的外掛，ADT提供了Android專案與工具的整體支援。

1. 啟動Eclipse，選擇Help > Software Updates > Find and Install....
   
   
   
2. 對話視窗出現後，選擇Search for new features to install後按Next.
3. 按New Remote Site .
   
   
4. 在最後的對話視窗的remote site鍵入名稱(如Android 外掛)與以下URL
   https://dl-ssl।google।com/android/eclipse/
   後按OK
5. 然後您會看到新站台出現在搜尋清單上(且被選取)，按Finish.
6. 在接下來的搜尋結果對話視窗核取然Android Plugin > Eclipse Integration > Android Development Tools 後按Next.
7. 閱讀許可條款, 如果同意的話選取Accept terms of the license agreement，按Next
8. 按finish.
9. ADT外掛未經簽署，您可以按Install All. 同意安裝
10. 重新啟動Eclipse
11. 重新啟動後，更新您的Eclipse的preferences 指定SDK的目錄路徑
    A.選擇Window > Preferences... 開啟Preferences panel. (Mac OS X: Eclipse > Preferences)
    B.選擇左邊版面的Android
    C.在主版面上的SDK Location ，按Browse... ，指定SDK的目錄路徑
    D.按apply後再按OK
    

最後再安裝Android SDK