获取系统信息

System.java

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);