[Android范例] 判断手机是否已安装某程序的小示例

public boolean isApkAvailable(String packagename) {   PackageInfo packageInfo;        try {             packageInfo = this.getPackageManager().getPackageInfo(                     packagename, 0);         } catch (NameNotFoundException e) {             packageInfo = null;         }         if(packageInfo ==null){             return false;        }else{          return true;        }    } 

?

if(isApkAvailable("包名")){     Intent intent = new Intent();                 intent = getPackageManager().getLaunchIntentForPackage("包名");                 startActivity(intent);   }else{//未安装，跳转至market下载该程序     Uri uri = Uri.parse("market://details?id=包名");                Intent it = new Intent(Intent.ACTION_VIEW, uri);                 startActivity(it);    }

?

if(isAvilible( "包名")){ Intent i = new Intent(); ComponentName cn = new ComponentName("包名", "包名.Activity"); i.setComponent(cn); startActivityForResult(i, RESULT_OK); } //未安装，跳转至market下载该程序 else { Uri uri = Uri.parse("market://details?id=包名");//id为包名 Intent it = new Intent(Intent.ACTION_VIEW, uri); startActivity(it); } 

?

Intent intent = new Intent(Intent.ACTION_VIEW);intent.setData(Uri.parse("market://details?id=" + getPackageName()));

?