Android Data binding : Cannot resolve symbol

问题:

I have tried to use the beta features(data binding) in the android studio. After following the guides from the android studio, I can find the related class DataBindingInfo in the android studio. But the databinding class does not generate after I create the project. Can someone help?

build.gradle for the app module

apply plugin: 'com.android.application'

apply plugin: 'com.android.databinding'
android {
    compileSdkVersion 23
    buildToolsVersion "23.0.1"

    defaultConfig {
        applicationId "com.example.pigfamily.myapplication"
        minSdkVersion 15
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:23.0.1'
}

build.gradle for the project

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        dependencies {
            classpath "com.android.tools.build:gradle:1.3.0"
            classpath "com.android.databinding:dataBinder:1.0-rc1"
        }
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        jcenter()
    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">

    <data>

        <variable
            name="user"
            type="com.example.pigfamily.myapplication.User" />
    </data>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
 >

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@{user.name}" />

    </LinearLayout>
</layout>

MainActivity.java

package com.example.pigfamily.myapplication;

import android.databinding.DataBindingUtil;
import android.databinding.ViewDataBinding;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ActivityMainBinding //cannot resolve the symbol here
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

回答1:

enable dataBinding in your App Level build.gradle file

android {
    ...
    dataBinding{
        enabled=true
    }
}

回答2:

I had this same problem. I was digging through gradle settings, cleaning, rebuilding... nothing worked. Finally all I had to do was restart Android Studio

https://www.bignerdranch.com/blog/descent-into-databinding/

As of this writing, this integration needs a little jump-start to get going. To make ListItemCrimeBinding available after adding the tag, you must restart Android Studio, then rebuild the project.

回答3:

Either click sync if a dialogue pops up, hit the sync button next to save, or restart Android Studio.

回答4:

1.Add Below in app gradle

 dataBinding {
        enabled = true
    }

2.In xml layout write below code

<layout
    xmlns:android="http://schemas.android.com/apk/res/android">
  <data></data>
</layout>

3.Most Important because of which databinding is not generating . INTERNET PERMISSION

Add Below code in manifest

  <uses-permission android:name="android.permission.INTERNET"/>

UPDATED: CLEAN AND REBUILD THE PROJECT