查找已安裝的應用程序或不併顯示對話框

Question

如何檢查應用程序被安裝或沒有後點擊按鈕，如果從谷歌沒有安裝對話框顯示下載的應用程序發揮 的Java/Android的

Answer 1

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

      System.out.println("App is already installed on your phone");   
     } else { 
      System.out.println("App is not currently installed on your phone"); 
     } 
    } 

    private boolean appInstalledOrNot(String uri) { 
     PackageManager pm = getPackageManager(); 
     try { 
      pm.getPackageInfo(uri, PackageManager.GET_ACTIVITIES); 
      return true; 
     } catch (PackageManager.NameNotFoundException e) { 
     } 

     return false; 
    } 

} 

Answer 2

這裏是方法。

private boolean isPackageInstalled(String packagename) { 
    PackageInfo info = null; 
    boolean isInstalled = false; 
    PackageManager pm = getPackageManager(); 
    try { 
     info = pm.getPackageInfo(packagename, PackageManager.GET_ACTIVITIES); 
     isInstalled = true; 
    } catch (Exception e) { 
     e.printStackTrace(); 
    } 
    return isInstalled; 
} 

該方法將返回true或false.You可以調用它如下。

if(isPackageInstalled("Your package name")) { 
    /*Perform task when package is installed*/ 
}