android初应用

android初使用
<intent-filter>
                <action android:name="qq.aa.TT" />
                <category android:name="android.intent.category.DEFAULT" />
            </intent-filter>

intent filter 限制哪些intent可以访问此activity(能接收什么类型的intent).
action(0个或多个),匹配其中一个即可.顺序component,如果没有则action,data,category,删除不匹配的,选择匹配中优先级最高的.

google map api需要注册key
    To display Maps data in a MapView, you need to register for a Maps API Key
    Each Maps API Key is uniquely associated with a specific certificate, based on an MD5 fingerprint of the certificate
    Each MapView must reference a Maps API Key, and the Key referenced must be registered to the certificate used to sign the application
    All MapView elements in an application can reference the same Maps API Key
    You can register multiple certificates under your developer identity
    You can get a temporary Maps API Key based on your debug certificate, but before you publish your application, you must register for a new Key based on your release certificate and update references in your MapViews accordingly