Displaying a Toast message from the Application class

Question

I have several classes in my application. Some are Activities, Services and Pure java classes. I know i can display a Toast message from within an Activity but i'd like to display a Toast from a pure java class.

In the java class i pass a context in to the constructor but this doesn't seem to show the toast.

I have created a method in the Application class that takes a String as an argument, hoping i could generate a Toast using the Application context, no joy here either.

How can i generate a Toast from a class that isn't a service or Activity etc.

public class LoginValidate{

public LoginValidate(Context context) {

        this.context = context;

        nfcscannerapplication = (NfcScannerApplication) context
                .getApplicationContext();


    }

public void someMethod(){

nfcscannerapplication.showToastMessage(result);

}

}

.

///then in my Application class

public void showToastMessage(String message){

            Toast.makeText(this.getApplictionContext(), "Encountered a problem with sending tag: " + message, Toast.LENGTH_LONG).show();

    }

@kalyanpvs Hi, yes i have tried it and it does display the message but the Toast message does not disappear. It stays on the screen even if i exit the app. How can i remove the message after a few seconds. I've read somewhere it's to do with creating the toast outside a context?? — turtleboy, Dec 23 '13 at 11:57
@turtleboy toast message disapper after their some time..you dont remove the toast message after some time.. — kalyan pvs, Dec 23 '13 at 12:06
@kalyanpvs yes it should disappear after a time which is determined by Toast.LENGTH_LONG. It is not however, it remains on the screen indefinitely. Any ideas why? — turtleboy, Dec 23 '13 at 12:09
@turtleboy once debub and check that method is how many times calling.. — kalyan pvs, Dec 23 '13 at 12:11

kalyan pvs · Answer 1 · 2013-12-23T11:30:36.063

First create Application class like this..

public class ApplicationContext extends Application {

/** Instance of the current application. */
private static ApplicationContext instance;

/**
 * Constructor.
 */
public ApplicationContext() {
    instance = this;
}

/**
 * Gets the application context.
 * 
 * @return the application context
 */
public static Context getContext() {
    if (instance == null) {
        instance = new ApplicationContext();
    }
    return instance;
}

/**
     * display toast message
     * 
     * @param data
     */
    public static void showToast(String data) {
        Toast.makeText(getContext(), data,
                Toast.LENGTH_SHORT).show();
    }

}

call this method from any of your class like ApplicationContext.showToast("your string");

be careful about context object leaking..

got this error: ```java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.res.Resources android.content.Context.getResources()' on a null object reference``` — kangear, Sep 29 '15 at 12:19

score 6 · Answer 2 · answered Dec 23 '13 at 11:27

There are two ways you can do that, if you have a valid context, you can do it like @CapDroid wrote:

public static void showToastWithTitle(String title) {
    Toast.makeText(getApplicationContext(), title, Toast.LENGTH_LONG).show();
}

if you don't, you can send a Context as well,

public static void showToastWithTitleAndContext(Context context, String title) {
    Toast.makeText(context, title, Toast.LENGTH_LONG).show();
}

Note that you can define a static Context in your Application.java and use it to call shoh toast.

hope that helps.

score 4 · Answer 3 · answered Dec 23 '13 at 11:19

4

Write this method in your Application Class. You just need to pass message in parameter from any Activity.

public void showToast(String message)
{
    Toast.makeText(getApplicationContext(), message, Toast.LENGTH_SHORT).show();
}

answered Dec 23 '13 at 11:19

Niranj Patel

32,980
10
97
133

Hi, also i'm not calling the toast message from within an Activity. I'm calling the Toast from a plain Java class. This is why it is not displaying. – turtleboy Dec 23 '13 at 12:00
without context reff you can't show toast.. you must need to pass context from activity to non-activity class – Niranj Patel Dec 23 '13 at 12:02
Nice. And simple. For `kotlin`, just use `applicationContext` – Free Dorfman Apr 09 '22 at 02:50

score 1 · Answer 4 · edited Dec 06 '18 at 14:55

1

It worked for me with :

Toast.makeText(this.getContext(), R.string.title, Toast.LENGTH_LONG).show();

edited Dec 06 '18 at 14:55

סטנלי גרונן

2,917
23
46
68

answered Dec 06 '18 at 13:11

Guest123

11
7

Vimalathithan A · Answer 5 · 2018-12-06T13:56:51.810

1

Need to pass the context to the showToastMessage(String message)

Like this showToastMessage(String message, Context context)

//then in my Application class

public void showToastMessage(String message, Context context){

            Toast.makeText(context, "Encountered a problem with sending tag: " + message, Toast.LENGTH_LONG).show();

    }

edited Dec 06 '18 at 13:56

answered Dec 06 '18 at 13:31

Vimalathithan A

50
7

score 0 · Answer 6 · edited Sep 05 '17 at 10:21

0

Toast.makeText(getActivity(), "Index....."+index, Toast.LENGTH_LONG).show();

edited Sep 05 '17 at 10:21

IntelliJ Amiya

74,896
15
165
198

answered Jul 28 '14 at 11:50

ashish

217
1
11

score 0 · Answer 7 · answered Aug 25 '22 at 20:56

0

Pass the message from other class using function parameter

public void showToast(String message) {

Toast.makeText(getApplicationContext(), message, Toast.LENGTH_SHORT).show();

}

answered Aug 25 '22 at 20:56

NANDINI MAURYA

1
1

Displaying a Toast message from the Application class

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