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();

    }

Answer 1

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..