小编cha*_*ghe的帖子

我正在开发一个MEAN堆栈Web应用程序,我想使用ng2-file-upload上传文件.这是我的Angular 2代码.

classroom.component.html

    <input type="file" class="form-control" name="single" ng2FileSelect [uploader]="uploader" />
    <button type="button" class="btn btn-success btn-s"
                  (click)="uploader.uploadAll()" [disabled]="!uploader.getNotUploadedItems().length">
            <span class="glyphicon glyphicon-upload"></span> Upload all
          </button><br />

classroom.component.ts

uploader:FileUploader = new FileUploader({url: "http://localhost:3000/api/material/create-material"});

在server.js中

app.use(cors());
app.use('/api',api);
app.use('/api/material',material);

并在material.js

var storage = multer.diskStorage({ //multers disk storage settings
    destination: function (req, file, cb) {
        cb(null, './uploads/');
    },
    filename: function (req, file, cb) {
        var datetimestamp = Date.now();
        cb(null, file.fieldname + '-' + datetimestamp + '.' + file.originalname.split('.')[file.originalname.split('.').length -1]);
    }
});

var upload = multer({ //multer …

我想在我的项目中添加一个materialdrawer库.当我添加依赖项时,我的build.gradle看起来像这样

 dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:22.1.1'
    compile('com.mikepenz:materialdrawer:4.4.8@aar') {
        transitive = true
    }
  }

但后来我得到以下错误,

>Error:A problem occurred configuring project ':app'.  
> Could not resolve all dependencies for configuration ':app:_debugCompile'.
   > Could not find com.android.support:appcompat-v7:23.1.1.
     Searched in the following locations:
         https://jcenter.bintray.com/com/android/support/appcompat-v7/23.1.1/appcompat-v7-23.1.1.pom
         https://jcenter.bintray.com/com/android/support/appcompat-v7/23.1.1/appcompat-v7-23.1.1.jar
         file:/C:/Users/abeys/AppData/Local/Android/sdk/extras/android/m2repository/com/android/support/appcompat-v7/23.1.1/appcompat-v7-23.1.1.pom
         file:/C:/Users/abeys/AppData/Local/Android/sdk/extras/android/m2repository/com/android/support/appcompat-v7/23.1.1/appcompat-v7-23.1.1.jar
         file:/C:/Users/abeys/AppData/Local/Android/sdk/extras/google/m2repository/com/android/support/appcompat-v7/23.1.1/appcompat-v7-23.1.1.pom
         file:/C:/Users/abeys/AppData/Local/Android/sdk/extras/google/m2repository/com/android/support/appcompat-v7/23.1.1/appcompat-v7-23.1.1.jar
     Required by:
         MyApplication4:app:unspecified
         MyApplication4:app:unspecified > com.mikepenz:materialdrawer:4.4.8
         MyApplication4:app:unspecified > com.mikepenz:materialdrawer:4.4.8 > com.mikepenz:materialize:0.2.8
         MyApplication4:app:unspecified > com.mikepenz:materialdrawer:4.4.8 > com.mikepenz:iconics-core:2.2.0
   > Could not find com.android.support:recyclerview-v7:23.1.1.
     Searched in the following locations:
         https://jcenter.bintray.com/com/android/support/recyclerview-v7/23.1.1/recyclerview-v7-23.1.1.pom
         https://jcenter.bintray.com/com/android/support/recyclerview-v7/23.1.1/recyclerview-v7-23.1.1.jar
         file:/C:/Users/abeys/AppData/Local/Android/sdk/extras/android/m2repository/com/android/support/recyclerview-v7/23.1.1/recyclerview-v7-23.1.1.pom
         file:/C:/Users/abeys/AppData/Local/Android/sdk/extras/android/m2repository/com/android/support/recyclerview-v7/23.1.1/recyclerview-v7-23.1.1.jar
         file:/C:/Users/abeys/AppData/Local/Android/sdk/extras/google/m2repository/com/android/support/recyclerview-v7/23.1.1/recyclerview-v7-23.1.1.pom …

我有一个使用jdk 8并启用Jack Options的android应用程序模块。然后，将其转换为Android Library模块。然后，我必须从构建gradle中删除Jack选项。现在，当我尝试构建AAR文件时，Lambda表达式给了我以下错误。

Error:(59, 25) error: cannot find symbol method metafactory(Lookup,String,MethodType,MethodType,MethodHandle,MethodType)

给出此错误的代码是，

Runnable r= () -> {
      appManager.startApp(definition,identifier);
};

我的构建摇篮是

Apply plugin: 'com.android.library'

android {
    compileSdkVersion 26
    buildToolsVersion "26.0.0"
    defaultConfig {
        minSdkVersion 18
        targetSdkVersion 26
        versionCode 1
        versionName "1.0"

    testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
}

compileOptions {
    sourceCompatibility JavaVersion.VERSION_1_8
    targetCompatibility JavaVersion.VERSION_1_8
}
}

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.android.support:appcompat-v7:26.+'
    compile …

在我的android项目中,我将两个库作为JAR包含在libs文件夹中.我将它们添加到构建Gradle中,如下所示.

dependencies {
    compile files('libs/siddhi-core-4.0.0-M13-SNAPSHOT.jar')
    compile files('libs/siddhi-execution-math-4.0.2-SNAPSHOT.jar')
}

这两个jar文件有一个同名的文件("org.wso2.siddhi.annotation.Extension"),但内容不同.这两个文件对项目都很重要.由于它具有相同的名称gradle不会建立说法

Duplicate files copied in APK

如何将这两个文件合并为一个具有相同名称的文件？这两个文件是带有类名列表的文本文件.在两个文件中,它们有两个不同的列表.所以我想将它们合并到一个具有相同名称的文本文件中的列表中.

我正在使用java.util.regex.Pattern类来匹配Android程序中的字符串。

if(Pattern.matches("\\{\\{.*?}}", element.getValue())) {
   ...             
} else {
   ...
}

我得到了以下错误。

 Caused by: java.util.regex.PatternSyntaxException: Syntax error in regexp pattern near index 8
                                                                  \{\{.*?}}

我正在使用Android Studio和Open JDK。为了测试正则表达式，我在Netbeans中编写了一个简单程序，它工作正常。Netbeans也使用openjdk。

System.out.println(Pattern.matches("\\{\\{.*?}}", "{{hello:sdf}}"));

为什么正则表达式在android项目中给出错误？

在这里我认为应该显示我的本地机器。但它没有显示。所以我无法连接到它。解决这个问题的办法是什么？

我用Python编写了这段代码:

x=345**3
z=float(x)**(1.0/3.0)
print z
print z.is_integer()

输出是:

345.0
False

这是为什么？我期待输出True.

这是我输入的代码.这里int的值没有在函数之外改变,但是list的值已经改变了.我期待list的值不会改变.是什么原因？

>>> def p1(list1):
    list1[0]=1000

>>> def p2(i):
    i+=10

>>> li=[1,2,3,4,5]
>>> int1=10
>>> p1(li)
>>> p2(int1)
>>> li
[1000, 2, 3, 4, 5]
>>> int1
10