Java 如何重新启动或恢复活动

如果连接被禁用，我想在更改wifi设置菜单时重新启动活动。 这是我的代码（onCreate方法）：

这是显示对话框的代码：

    @Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    // Use the Builder class for convenient dialog construction
    // 1. Instantiate an AlertDialog.Builder with its constructor
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    // 2. Chain together various setter methods to set the dialog characteristics
    builder.setTitle("Connection Error !")
           .setMessage("Please check your Internet Connection for start the application.")
           .setPositiveButton("Back to Settings", new DialogInterface.OnClickListener() {
               public void onClick(DialogInterface dialog, int id) {
                   Intent intent=new Intent();
                   intent.setComponent(new ComponentName("com.android.settings", "com.android.settings.WirelessSettings"));
                   startActivity(intent);
               }
           });
    // Create the AlertDialog object and return it
    return builder.create();
}

当用户将wifi网络更改为“开”时，我如何重新启动或恢复应用程序以检查网络连接

感谢使用onRestart方法

protected void onRestart() {

    super.onRestart();
}

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我认为，如果你需要重新启动活动，那么你的设计就有问题了

startActivity(getIntent());
finish();

这将从“活动”中调用recreate（）来完成此操作

 public void recreate ()

---

使用新实例重新创建此活动。这导致的流程与由于配置更改而创建活动时的流程基本相同——当前实例将通过其生命周期进入onDestroy（），然后再创建一个新实例。

尝试将第一块代码放入onResume（）方法中

当从WirelessSettings返回到activity时，调用onResume方法并为status var分配一个新值

 Try this one.

 @Override
  protected void onResume() {
    super.onResume();
    notify("onResume");
  }

or

@Override
protected void onStart() {
    super.onStart();  // Always call the superclass method first

    // The activity is either being restarted or started for the first time
    // so this is where we should make sure that GPS is enabled
    LocationManager locationManager = 
            (LocationManager) getSystemService(Context.LOCATION_SERVICE);
    boolean gpsEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);

    if (!gpsEnabled) {
        // Create a dialog here that requests the user to enable GPS, and use an intent
        // with the android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS action
        // to take the user to the Settings screen to enable GPS when they click "OK"
    }
}

@Override
protected void onRestart() {
    super.onRestart();  // Always call the superclass method first

    // Activity being restarted from stopped state    
}

请访问此链接。

---

onCreateDialog方法位于我在onCreate方法中调用的另一个类中。。如果连接被禁用，该对话框将向用户发送wifi设置并打开wifi连接。当用户返回到应用程序时，我如何重新检查连接？您可以在将用户发送到网络设置时发出一个标志，并在OnResume（）中检查连接，只要该标志位于我正在使用布尔值解析的数据库上。如果用户转到设置页面，则为TRUE；如果按下取消按钮，则为FALSE。

 Try this one.

 @Override
  protected void onResume() {
    super.onResume();
    notify("onResume");
  }

or

@Override
protected void onStart() {
    super.onStart();  // Always call the superclass method first

    // The activity is either being restarted or started for the first time
    // so this is where we should make sure that GPS is enabled
    LocationManager locationManager = 
            (LocationManager) getSystemService(Context.LOCATION_SERVICE);
    boolean gpsEnabled = locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);

    if (!gpsEnabled) {
        // Create a dialog here that requests the user to enable GPS, and use an intent
        // with the android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS action
        // to take the user to the Settings screen to enable GPS when they click "OK"
    }
}

@Override
protected void onRestart() {
    super.onRestart();  // Always call the superclass method first

    // Activity being restarted from stopped state    
}