Toast - Android Full Tutorial

Android - Toast

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Creating a custom Toast

If you don't want to use the default Toast view, you can provide your own using the setView(View) method on a Toast object.

First, create the XML layout you would like to use in your Toast.

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/toast_layout_root"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="8dp"
    android:background="#111">

    <TextView android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="#FFF"/>

    <TextView android:id="@+id/description"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="#FFF"/>

</LinearLayout>

Then, when creating your Toast, inflate your custom View from XML, and call setView

// Inflate the custom view from XML
LayoutInflater inflater = getLayoutInflater();
View layout = inflater.inflate(R.layout.custom_toast_layout,
                               (ViewGroup) findViewById(R.id.toast_layout_root));

// Set the title and description TextViews from our custom layout
TextView title = (TextView) layout.findViewById(R.id.title);
title.setText("Toast Title");

TextView description = (TextView) layout.findViewById(R.id.description);
description.setText("Toast Description");

// Create and show the Toast object

Toast toast = new Toast(getApplicationContext());
toast.setGravity(Gravity.CENTER, 0, 0);
toast.setDuration(Toast.LENGTH_LONG);
toast.setView(layout);
toast.show();

Set position of a Toast

A standard toast notification appears at the bottom of the screen aligned in horizontal centre. You can change this position with the setGravity(int, int, int). This accepts three parameters: a Gravity constant, an x-position offset, and a y-position offset.

For example, if you decide that the toast should appear in the top-left corner, you can set the gravity like this:

toast.setGravity(Gravity.TOP|Gravity.LEFT, 0, 0);

Showing a Toast Message

In Android, a Toast is a simple UI element that can be used to give contextual feedback to a user.

To display a simple Toast message, we can do the following.

// Declare the parameters to use for the Toast

Context context = getApplicationContext(); 
// in an Activity, you may also use "this"
// in a fragment, you can use getActivity()

CharSequence message = "I'm an Android Toast!";
int duration = Toast.LENGTH_LONG; // Toast.LENGTH_SHORT is the other option

// Create the Toast object, and show it!
Toast myToast = Toast.makeText(context, message, duration);
myToast.show();

Or, to show a Toast inline, without holding on to the Toast object you can:

Toast.makeText(context, "Ding! Your Toast is ready.", Toast.LENGTH_SHORT).show();

IMPORTANT: Make sure that the show() (opens new window) method is called from the UI thread. If you're trying to show a Toast from a different thread you can e.g. use runOnUiThread (opens new window) method of an Activity (opens new window).

Failing to do so, meaning trying to modify the UI by creating a Toast, will throw a RuntimeException which will look like this:

java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()

The simplest way of handling this exception is just by using runOnUiThread: syntax is shown below.


  runOnUiThread(new Runnable() {
        @Override
        public void run() {
            // Your code here
        }
    });

Show Toast Message Above Soft Keyboard

By default, Android will display Toast messages at the bottom of the screen even if the keyboard is showing. This will show a Toast message just above the keyboard.

public void showMessage(final String message, final int length) {
    View root = findViewById(android.R.id.content);
    Toast toast = Toast.makeText(this, message, length);
    int yOffset = Math.max(0, root.getHeight() - toast.getYOffset());
    toast.setGravity(Gravity.TOP | Gravity.CENTER_HORIZONTAL, 0, yOffset);
    toast.show();
}

Thread safe way of displaying Toast (Application Wide)

public class MainApplication extends Application {
    
    private static Context context; //application context

    private Handler mainThreadHandler;
    private Toast toast;

    public Handler getMainThreadHandler() {
        if (mainThreadHandler == null) {
            mainThreadHandler = new Handler(Looper.getMainLooper());
        }
        return mainThreadHandler;
    }

    @Override public void onCreate() {
        super.onCreate();
        context = this;
    }
       
    public static MainApplication getApp(){
        return (MainApplication) context;
    }

    /**
     * Thread safe way of displaying toast.
     * @param message
     * @param duration
     */
    public void showToast(final String message, final int duration) {
        getMainThreadHandler().post(new Runnable() {
            @Override
            public void run() {
                if (!TextUtils.isEmpty(message)) {
                    if (toast != null) {
                        toast.cancel(); //dismiss current toast if visible
                        toast.setText(message);
                    } else {
                        toast = Toast.makeText(App.this, message, duration);
                    }
                    toast.show();
                }
            }
        });
    }

Remember to add MainApplication in manifest.

Now call it from any thread to display a toast message.

MainApplication.getApp().showToast("Some message", Toast.LENGTH_LONG);

Thread safe way of displaying a Toast Message (For AsyncTask)

If you don't want to extend Application and keep your toast messages thread safe, make sure you show them in the post execute section of your AsyncTasks.

public class MyAsyncTask extends AsyncTask <Void, Void, Void> {

    @Override
    protected Void doInBackground(Void... params) {
        // Do your background work here
    }

    @Override
    protected void onPostExecute(Void aVoid) {
        // Show toast messages here
        Toast.makeText(context, "Ding! Your Toast is ready.",   Toast.LENGTH_SHORT).show();
    }
    
}

Syntax

Toast makeText (Context context, CharSequence text, int duration)

Toast makeText (Context context, int resId, int duration)

- void setGravity(int gravity, int xOffset, int yOffset) - void show()

Parameters

Parameter	Details
context	The context to display your Toast in. `this` is commonly used in an Activity and `getActivity()` is commonly used in a Fragment
text	A CharSequence that specifies what text will be shown in the Toast. Any object that implements CharSequence can be used, including a String
resId	A resource ID that can be used to provide a resource String to display in the Toast
duration	Integer flag representing how long the Toast will show. Options are `Toast.LENGTH_SHORT` and `Toast.LENGTH_LONG`
gravity	Integer specifying the position, or "gravity" of the Toast. See options here (opens new window)
xOffset	Specifies the horizontal offset for the Toast position
yOffset	Specifies the vertical offset for the Toast position

Remarks

A toast provides simple feedback about an operation in a small popup. It only fills the amount of space required for the message and the current activity remains visible and interactive.

A more recent alternative to Toast is SnackBar. SnackBar offers an updated visual style and allows the user to dismiss the message or take further action. See the SnackBar (opens new window) documentation for details.

Official Documentation:

https://developer.android.com/reference/android/widget/Toast.html (opens new window)

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