android PackageManager.setApplicationEnabledSetting()

/**
     * Flag for {@link #setApplicationEnabledSetting(String, int, int)}
     * and {@link #setComponentEnabledSetting(ComponentName, int, int)}: This
     * component or application is in its default enabled state (as specified
     * in its manifest).
     */
    public static final int COMPONENT_ENABLED_STATE_DEFAULT = 0;
    /**
     * Flag for {@link #setApplicationEnabledSetting(String, int, int)}
     * and {@link #setComponentEnabledSetting(ComponentName, int, int)}: This
     * component or application has been explictily enabled, regardless of
     * what it has specified in its manifest.
     */
    public static final int COMPONENT_ENABLED_STATE_ENABLED = 1;
    /**
     * Flag for {@link #setApplicationEnabledSetting(String, int, int)}
     * and {@link #setComponentEnabledSetting(ComponentName, int, int)}: This
     * component or application has been explicitly disabled, regardless of
     * what it has specified in its manifest.
     */
    public static final int COMPONENT_ENABLED_STATE_DISABLED = 2;
    /**
     * Flag for {@link #setApplicationEnabledSetting(String, int, int)} only: The
     * user has explicitly disabled the application, regardless of what it has
     * specified in its manifest.  Because this is due to the user's request,
     * they may re-enable it if desired through the appropriate system UI.  This
     * option currently <strong>can not</strong> be used with
     * {@link #setComponentEnabledSetting(ComponentName, int, int)}.
     */
    public static final int COMPONENT_ENABLED_STATE_DISABLED_USER = 3;
//以上几个常量可以用于使用APK
getPackageManager().setApplicationEnabledSetting("com.android.vending", PackageManager.COMPONENT_ENABLED_STATE_ENABLED, 0);
//若在此方法之前已经把com.android.vending DISABLE, 那么,这句代码呢,就是重新使com.android.vending ENABLED
//用于隐藏APK很是实用.