Android service 调用

Intent intent = new Intent("com.ryg.MessengerService.launch");//5.0以后调用服务必须是显示调用，
bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
这时候会报错：
llegalArgumentException: Service Intent must be explicit

也可以隐式调用 如下：本质也是解析出service名字进行显示调用

final Intent intent = new Intent();
        intent.setAction("com.ryg.MessengerService.launch");
        final Intent eintent = new Intent(createExplicitFromImplicitIntent(this,intent));
        bindService(eintent,mConnection, Context.BIND_AUTO_CREATE);

/***
     * Android L (lollipop, API 21) introduced a new problem when trying to invoke implicit intent,
     * "java.lang.IllegalArgumentException: Service Intent must be explicit"
     *
     * If you are using an implicit intent, and know only 1 target would answer this intent,
     * This method will help you turn the implicit intent into the explicit form.
     *
     * Inspired from SO answer: http://stackoverflow.com/a/26318757/1446466
     * @param context
     * @param implicitIntent - The original implicit intent
     * @return Explicit Intent created from the implicit original intent
     */
    public static Intent createExplicitFromImplicitIntent(Context context, Intent implicitIntent) {
        // Retrieve all services that can match the given intent
        PackageManager pm = context.getPackageManager();
        List<ResolveInfo> resolveInfo = pm.queryIntentServices(implicitIntent, 0);

        // Make sure only one match was found
        if (resolveInfo == null || resolveInfo.size() != 1) {
            return null;
        }

        // Get component info and create ComponentName
        ResolveInfo serviceInfo = resolveInfo.get(0);
        String packageName = serviceInfo.serviceInfo.packageName;
        String className = serviceInfo.serviceInfo.name;
        ComponentName component = new ComponentName(packageName, className);

        // Create a new intent. Use the old one for extras and such reuse
        Intent explicitIntent = new Intent(implicitIntent);

        // Set the component to be explicit
        explicitIntent.setComponent(component);

        return explicitIntent;
    }