Android Studio-To run dex in process, the Gradle daemon needs a larger heap

报错

Running dex as a separate process.

To run dex in process, the Gradle daemon needs a larger heap.
It currently has 1024 MB.
For faster builds, increase the maximum heap size for the Gradle daemon to at least 1536 MB.
To do this set org.gradle.jvmargs=-Xmx1536M in the project gradle.properties.

原因

由于gradle编译时的内存资源不足，需要配置更大的内存资源。

解决方案

1.首先在app下的build.gradle文件加上dexOptions {javaMaxHeapSize "2g"}

 android {  
        compileSdkVersion 23  
        buildToolsVersion "23.0.2"  
        ...  
        dexOptions {  
            javaMaxHeapSize "2g"  
        }  
    }  

2.最后在项目根目录查找gradle.properties这个文件，如果没有就新建一个，加入以下内容

org.gradle.daemon=true #就是让你让你编译时使用守护进程。
org.gradle.parallel=true #使用并行编译
org.gradle.jvmargs=-Xmx2048m #JVM最大允许分配的堆内存，按需分配

至于2048这个数字根据它提示的修改，然后编译同步gradle，run成功。