android - 查看是否安装了应用程序

Question

我认为这个问题说明了一切：找出用户是否在手机上安装了 Facebook 或 Whatsapp 的最佳方法是什么？我是否必须检查包裹或最好的方法是什么？

Answer 1

这是问题在这里得到了回答。您可以使用以下代码检查包名称

com.facebook.android 或 com.facebook.katana

代码：

public class Example extends Activity
    {
        @Override
        protected void onCreate(Bundle savedInstanceState)
        {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            //Put the package name here...
            boolean installed  =   appInstalledOrNot("com.facebook.android");  
            if(installed)
            {
            //This intent will help you to launch if the package is already installed
            Intent LaunchIntent = getPackageManager()
                .getLaunchIntentForPackage("com.facebook.android");
        startActivity(LaunchIntent);


                      System.out.println("App already installed om your phone");


            }
            else
            {
                System.out.println("App is not installed om your phone");
            }
        }
        private boolean appInstalledOrNot(String uri)
        {
            PackageManager pm = getPackageManager();
            boolean app_installed = false;
            try
            {
                   pm.getPackageInfo(uri, PackageManager.GET_ACTIVITIES);
                   app_installed = true;
            }
            catch (PackageManager.NameNotFoundException e)
            {
                   app_installed = false;
            }
            return app_installed ;
    }
    }