微信支付提示“系统未安装微信服务“，实际已经有安装微信

我也是遇到过的，原来官方的登录demo在部分安卓手机上会出现这种情况，论坛里有大神给出过代码，现在我已将官方登录demo改成如下就正常：

owner.isInstalled = function(id) {  
        if (id === 'qihoo' && mui.os.plus) {  
            return true;  
        }  
        if (mui.os.android) {  
            //var main = plus.android.runtimeMainActivity();  
            //var packageManager = main.getPackageManager();  
            //var PackageManager = plus.android.importClass(packageManager)  
            var packageName = {  
                "qq": "com.tencent.mobileqq",  
                "weixin": "com.tencent.mm",  
                "sinaweibo": "com.sina.weibo"  
            }  
            plus.android.importClass('android.content.pm.PackageManager');  
            var MainActivity = plus.android.runtimeMainActivity();  
            var PackageManager = MainActivity.getPackageManager();  
            try {  
                //return packageManager.getPackageInfo(packageName[id], PackageManager.GET_ACTIVITIES);  
                if(packageName[id]){  
                    return plus.android.invoke(PackageManager, 'getLaunchIntentForPackage', packageName[id]) || null;  
                }else{  
                    return null;  
                }  
            } catch (e) {}  
        } else {  
            switch (id) {  
                case "qq":  
                    var TencentOAuth = plus.ios.import("TencentOAuth");  
                    return TencentOAuth.iphoneQQInstalled();  
                case "weixin":  
                    var WXApi = plus.ios.import("WXApi");  
                    return WXApi.isWXAppInstalled()  
                case "sinaweibo":  
                    var SinaAPI = plus.ios.import("WeiboSDK");  
                    return SinaAPI.isWeiboAppInstalled()  
                default:  
                    break;  
            }  
        }  
    }