39、在代码中添加权限（判断）

public class MainActivity extends Activity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        Hello.sayHello(this);
    }
}

public class Hello {
    public static final String PERMISSION_SAY_HELLO = "com.example.authoritydemo.permission.SAY_HELLO";
    
    public static void sayHello(Context cxt) {
        int checkResult = cxt.checkCallingOrSelfPermission(PERMISSION_SAY_HELLO);
        // 判断是否被允许
        if (checkResult != PackageManager.PERMISSION_GRANTED) {
            throw new SecurityException("执行方法需要com.example.authoritydemo.permission.SAY_HELLO权限");
        }
        Toast.makeText(cxt, "Say Hello www.baidu.com", Toast.LENGTH_SHORT).show();
    }
}

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.authoritydemo"
    android:versionCode="1"
    android:versionName="1.0" >
    <uses-sdk
        android:minSdkVersion="17"
        android:targetSdkVersion="17" />
    
    <permission android:name="com.example.authoritydemo.permission.SAY_HELLO" />
    <uses-permission android:name="com.example.authoritydemo.permission.SAY_HELLO" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>