Best way to avoid Toast accumulation in Android

Question

In Android, when I create Toast and show them, they appear consecutively. The problem is that I have a button that checks some fields and if the user enters incorrect data, a Toast is shown. If the user touches the button repeatedly, Toasts are accumulated and the message does not disappear for a couple of seconds.

Which is the best way to avoid that?

• May I save the reference to the last Toast and remove it before making a new one?
• Should I use the same Toast for all messages?
• Might I use any method that clears all the Application Toasts before making and showing the new one?

Answer 1

You can use the cancel() method of Toast to close a showing Toast.

Use a variable to keep a reference to every Toast as you show it, and simply call cancel() before showing another one.

private Toast mToast = null; // <-- keep this in your Activity or even in a custom Application class

//... show one Toast
if (mToast != null) mToast.cancel();
mToast = Toast.makeText(context, text, duration);
mToast.show();

//... show another Toast
if (mToast != null) mToast.cancel();
mToast = Toast.makeText(context, text, duration);
mToast.show();

// and so on.

You could even wrap that into a small class like so:

public class SingleToast {

    private static Toast mToast;

    public static void show(Context context, String text, int duration) {
        if (mToast != null) mToast.cancel();
        mToast = Toast.makeText(context, text, duration);
        mToast.show();
    }
}

and use it in your code like so:

SingleToast.show(this, "Hello World", Toast.LENGTH_LONG);

//

Answer 2

Have only one Toast in this activity.

private Toast toast = null;

Then just check if there's currently a Toast being shown before creating another one.

if (toast == null || !toast.getView().isShown()) {
    if (toast != null) {
        toast.cancel();
    }
    toast = Toast.makeToast("Your text", Toast.LENGTH).show();
}

You can even make that last snippet into a private method showToast(text) to refactor code if you need to display different text messages.