Android获取apk信息(版本、包名等)

public class Aike extends Activity {   
       
    @Override  
    public void onCreate(Bundle savedInstanceState) {   
        super.onCreate(savedInstanceState);          
        setContentView(R.layout.main);       
        String archiveFilePath="sdcard/download/Law.apk";//安装包路径   
        PackageManager pm = getPackageManager();     
        PackageInfo info = pm.getPackageArchiveInfo(archiveFilePath, PackageManager.GET_ACTIVITIES);     
        if(info != null){     
            ApplicationInfo appInfo = info.applicationInfo;     
            String appName = pm.getApplicationLabel(appInfo).toString();     
            String packageName = appInfo.packageName;  //得到安装包名称   
            String version=info.versionName;       //得到版本信息        
            Toast.makeText(test4.this, "packageName:"+packageName+";version:"+version, Toast.LENGTH_LONG).show();   
            Drawable icon = pm.getApplicationIcon(appInfo);//得到图标信息   
            TextView tv = (TextView)findViewById(R.id.tv); //显示图标   
            tv.setBackgroundDrawable(icon);   
        }     
  }   
  
}