diff --git a/app/build.gradle b/app/build.gradle
index e5923db..9b68fa3 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -32,7 +32,7 @@ android {
 
 dependencies {
     implementation fileTree(dir: 'libs', include: ['*.jar'])
-    implementation 'com.android.support.constraint:constraint-layout:1.1.3'
+    implementation 'com.android.support:appcompat-v7:27.1.1'
     testImplementation 'junit:junit:4.12'
 
     //基础功能依赖,必须