Concat two dynamic strings using Data Binding

Question

Is it possible to concat two dynamic strings using Data Binding?

My code looks like:

<TextView
                    android:id="@+id/text_view_activity_profile_name"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_below="@id/image_view_activity_profile_small_photo"
                    android:layout_centerHorizontal="true"
                    android:layout_marginTop="15dp"
                    android:text="@={userdata.firstName+' '+userdata.lastName}"
                    android:textColor="@color/white"
                    android:textSize="24sp" />

,but it is not the correct way : Error:(52, 42) The expression (firstNameUserdataCha) + (lastNameUserdata) cannot cannot be inverted: Two way binding with operator + supports only a single dynamic expressions.

set your textview in your java code with setText. – Mehran Zamani Feb 27 '17 at 15:34 — Mehran Zamani, Feb 27 '17 at 15:34

Carl Poole · Accepted Answer · 2017-02-27T15:15:21.657

23

Try it like this instead

android:text='@{userdata.firstName+" "+userdata.lastName}'

or alternately...

android:text='@{String.format("%s %s", userdata.firstName, userdata.lastName)}'

edited Feb 27 '17 at 15:15

answered Feb 27 '17 at 15:07

Carl Poole

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7

This is right. It is not possible to use two-way data binding (`@={...}` instead of `@{...}`) with string concatenation. A third (and better) option is to use resource formatting to support multiple languages: `android:text="@{@string/name(userdata.firstName, userdata.lastName)}"` – George Mount Feb 27 '17 at 23:45

Khemraj Sharma · Answer 2 · 2018-10-03T05:21:34.787

11

Below is recommended way.

It is also useful when you have localization/ multi language

Use string resource like this.

android:text="@{@string/generic_name(user.firstName,user.lastName)}"

and make string resource in strings.xml

<string name="generic_name">first name : %1$s and last name : %2$s</string>

You can check many other ways in this answer.

edited Oct 03 '18 at 05:21

answered Aug 07 '18 at 05:23

Khemraj Sharma

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score 2 · Answer 3 · answered Feb 27 '17 at 15:35

It doesn't compile since you're using two-way data binding. Android DataBinding generated class won't be able to assign back the value of the TextView to userData since there are two variables used. You can use one-way data binding instead:

android:text='@{userData.firstName + " " + userData.lastName}'

If you really want to use two-way data binding, then make a custom converter for that.

score 0 · Answer 4 · answered Aug 25 '21 at 10:06

                        <TextView
                        ..........
                        android:text='@{String.format("%s %s","+91", userInfo.mobile)}'
                        .............. />

try this if you want add multiple string

android:text='@{String.format("%s %s","+91", userInfo.mobile)}'

output: +91 0000000000

Concat two dynamic strings using Data Binding

4 Answers4

Below is recommended way.

try this if you want add multiple string