modify file

Author: CharonChui

BasicKnowledge/知识大杂烩.md

@@ -407,6 +407,11 @@ protected void setFullscreen(boolean on) {
     <style name="Theme" parent="android:Theme"></style>
     ```
 
+21.apk签名信息获取
+---
+
+/Users/xxx/Library/Android/sdk/build-tools/30.0.3/apksigner verify --print-certs xxx.apk    
+
 ---
 
 - 邮箱 ：charon.chui@gmail.com