android - 数据绑定(bind) Android - 类型参数 T 具有不兼容的上限 : ViewDataBinding and MainActivity

Question

我正在使用 Android Studio 2.0 Preview 4。我正在使用 Android SDK 工具 25 rc1。无论我清理/重建项目多少次，此错误都会持续存在。 File-> Invalidate Caches and restart 也不起作用。我无法运行最基本的数据绑定(bind)示例。

build.gradle 文件

apply plugin: 'com.android.application'

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.2"

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

    dataBinding {
        enabled = true
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    testCompile 'junit:junit:4.12'
    compile 'com.android.support:appcompat-v7:23.1.1'
    compile 'com.android.support:design:23.1.1'
}

MainActivity.java

package com.example.chiragshenoy.myapplication;

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

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        MainActivity binding = DataBindingUtil.setContentView(this, R.layout.activity_main);
        User user = new User("Test", "User");
        binding.setUser(user);
    }

    @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;
    }

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.chiragshenoy.myapplication.User"/>
    </data>
    <LinearLayout
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <TextView android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@{user.firstName}"/>
        <TextView android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@{user.lastName}"/>
    </LinearLayout>
</layout>

这是我的顶级 build.gradle 文件

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

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:2.0.0-alpha3'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        jcenter()
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

Answer 1

如果你的 gradle 版本没问题(1.5+)那么你应该试试这个:

1. 转到您的“some_layout.xml”
2. 单击右键 -> 重构 -> 重命名(或 SHIFT + F6)
3. 例如将布局重命名为“some_layout2.xml”
4. 将此文件重命名回原来的“some_layout.xml”

这可能会解决问题。让我们知道。