Data Binding and You

Lightning talk overview of data binding on Android. Presented at Airbnb's Taking Flight, May 31st, San Francisco, CA.

Transcript

1. Data Binding and You
   Siena Aguayo
   Software Engineer, Indiegogo
   @sienatime
   

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2. @sienatime
   What is data binding?
   

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3. @sienatime
   Attaches model data to your view
   public class Pikachu {
   public String name = "Pikachu";
   public String genus = "Mouse";
   public String type = "Electric";
   public int imageResource =
   R.drawable.sprite_25;
   }
   

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4. @sienatime
   One- and Two-Way Binding
   One-Way Binding Two-Way Binding
   Model
   View
   Model
   View
   

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5. @sienatime
   Why is data binding useful?
   

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6. @sienatime
   Eliminate boilerplate!
   TextView pokeName = (TextView) findViewById(R.id.poke_name);
   TextView pokeGenus = (TextView) findViewById(R.id.poke_genus);
   TextView pokeType = (TextView) findViewById(R.id.poke_type);
   pokeName.setText(pikachu.name);
   pokeGenus.setText(String.format(R.string.genus_format, pikachu.genus));
   pokeType.setText(pikachu.type)
   PikachuActivityBinding binding =
   DataBindingUtil.setContentView(this, R.layout.pikachu_activity);
   binding.setPikachu(new Pikachu());
   

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7. @sienatime
   How do I set it up?
   

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8. @sienatime
   Usage in build.gradle
   android {
   dataBinding {
   enabled = true
   }
   }
   dependencies {
   compile "com.android.support:appcompat-v7:23.4.0"
   }
   

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9. @sienatime
   Usage in XML
   
   
   
   
   
   ...
   android:text="@{pikachu.name}"/>
   ...
   android:text="@{@string/genus_format(pikachu.genus)}"/>
   ...
   android:text="@{pikachu.type}"/>
   
   
   

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10. @sienatime
    Custom @BindingAdapter
    XML
    ...
    android:imageResource=
    "@{pikachu.imageResource}"/>
    ImageViewBindings.java
    @BindingAdapter("android:imageResource")
    public static void setImage(ImageView view, int resourceId) {
    view.setImageDrawable(view.getContext().getDrawable(resourceId));
    }
    Pikachu.java
    public int imageResource =
    R.drawable.sprite_25;
    

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11. @sienatime
    Data binding works
    back to
    API 7!
    compile "com.android.support:appcompat-v7:23.4.0"
    

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12. @sienatime
    Further Reading
    ● Code used in this presentation https://github.com/sienatime/pikachu-data-
    binding
    ● Official documentation https://developer.android.com/topic/libraries/data-
    binding/index.html
    ● “Data Binding Techniques” by Jacob Tabak’s (video from Droidcon NYC 2015)
    https://www.youtube.com/watch?v=WdUbXWztKNY
    ● “Marshmallow Brings Data Bindings to Android” by Yiğit Boyar and George
    Mount (video and transcription from Bay Area Android Dev Group, Oct. 2015)
    https://realm.io/news/data-binding-android-boyar-mount/
    ● “Advanced Data Binding” by Yiğit Boyar (video from Google I/O 2016) https:
    //www.youtube.com/watch?v=DAmMN7m3wLU
    

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