Android 编程下获得应用程序的签名

源码及安装文件下载方式一：GetAppSignature.zip

说明：应用程序的签名被封装在 packageInfo 中，所以我们要获得应用程序的签名就需要获得 PackageManager 来获得包含有签名信息的 packageInfo，再通过 packageInfo 获得 Signature 数组，循环遍历将签名进行拼接。

代码运行效果：

package cn.sunzn.getappsignature;

import android.app.Activity;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.content.pm.Signature;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.Menu;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends Activity {

   private EditText et_pkgname;
   private TextView tv_signature;
   private PackageManager manager;
   private PackageInfo packageInfo;
   private Signature[] signatures;
   private StringBuilder builder;
   private String signature;

   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);
       et_pkgname = (EditText) findViewById(R.id.et_pkgname);
       tv_signature = (TextView) findViewById(R.id.tv_signature);
       manager = getPackageManager();
       builder = new StringBuilder();
   }

   public void getSignature(View view) {
       String pkgname = et_pkgname.getText().toString();
       boolean isEmpty = TextUtils.isEmpty(pkgname);
       if (isEmpty) {
           Toast.makeText(this, "应用程序的包名不能为空！", Toast.LENGTH_SHORT);
       } else {
           try {
               /** 通过包管理器获得指定包名包含签名的包信息 **/
               packageInfo = manager.getPackageInfo(pkgname, PackageManager.GET_SIGNATURES);
               /******* 通过返回的包信息获得签名数组 *******/
               signatures = packageInfo.signatures;
               /******* 循环遍历签名数组拼接应用签名 *******/
               for (Signature signature : signatures) {
                   builder.append(signature.toCharsString());
               }
               /************** 得到应用签名 **************/
               signature = builder.toString();
               tv_signature.setText(signature);
           } catch (NameNotFoundException e) {
               e.printStackTrace();
           }
       }
   }

   public boolean onCreateOptionsMenu(Menu menu) {
       getMenuInflater().inflate(R.menu.activity_main, menu);
       return true;
   }
}