Toast in Android

Toast notification is a short small message popped up on the window surface. It only fills in the space required by the message, and the user's current activity remains visible and interactive. This notification automatically fades in and out and does not accept user interaction events. The toast notification can be created and displayed by activity or service. If you create a toast notification from the service, it is displayed at the top of the current activity.

The following describes a common method in toast:

1. maketext () method

public static Toast makeText (Context context, CharSequence text, int duration)public static Toast makeText (Context context, int resId, int duration)

You can use the maketext () method to obtain a toast instance. The first maketext method has three parameters: 1. context of the application, 2. text message to be displayed; 3. the time when the toast notification is continuously displayed. Use the show () method to display the toast notification. You can also use strings in the resource file to display text.

Context context = getApplicationContext();CharSequence text = "Hello toast!";int duration = Toast.LENGTH_SHORT;Toast toast = Toast.makeText(context, text, duration);toast.show();

Of course, you can directly use the combination method and avoid creating a toast object:

Toast.makeText(context, text, duration).show();

2. setgravity ()

This method is simple. Set the toast display position:

Toast. setgravity (gravity. Center, 0, 0); // set the toast display position to center

3. setview ()

By viewing the toast source code, we found that this class contains a view variable mnextview, so we can use setview () to implement our custom toast requirements. This method allows us to use custom toast, as shown in the following example:

// Custom toast_layout.xml layout file <linearlayout xmlns: Android = "http://schemas.android.com/apk/res/android" Android: Id = "@ + ID/toast_layout_root" Android: Orientation = "horizontal" Android: layout_width = "fill_parent" Android: layout_height = "fill_parent" Android: padding = "8dp" Android: Background = "# daaa"> <imageview Android: src = "@ drawable/droid" Android: layout_width = "wrap_content" Android: layout_height = "wrap_content" Android: layout_marginright = "8dp"/> <textview Android: id = "@ + ID/text" Android: layout_width = "wrap_content" Android: layout_height = "wrap_content" Android: textcolor = "# fff"/> </linearlayout> // In the activity, layoutinflater Inflater = getlayoutinflater (); view layout = Inflater. inflate (R. layout. custom_toast, (viewgroup) findviewbyid (R. id. toast_layout_root); textview text = (textview) layout. findviewbyid (R. id. text); text. settext ("this is a custom toast"); Toast = new toast (getapplicationcontext (); toast. setgravity (gravity. center_vertical, 0, 0); toast. setduration (toast. length_long); toast. setview (layout); toast. show ();

Note: Do not use a public toast class constructor unless you use the setview (View) method to define layout. If you do not use custom layout, you must use the maketext (context, Int, INT) method to create toast.

For instance demonstration, you can refer to this example, which contains five different toast types and provides download:

Http://www.cnblogs.com/salam/archive/2010/11/10/1873654.html#2390550

Note the following:
When toast is used as the prompt message, toast is displayed at the bottom of the screen, which is generally used to prompt users for incorrect operations. In some cases, when a user tries to operate multiple times consecutively, many toast entries may appear, which are displayed in sequence and remain on the page for a long time, this will seriously affect the user affinity of the software. We can use the following method to show that the toast does not accumulate the time when the toast is not finished, but interrupts the current toast to display the new toast. In this way, toast will not stay on the interface for a long time. A maximum of one toast prompt time is displayed.

 

　　private Toast toast = null;        private void showTextToast(String msg) {        if (toast == null) {            toast = Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_SHORT);        } else {            toast.setText(msg);        }        toast.show();    }