[移动开发]Android Hilt

Hilt基础使用

添加依赖

custom.gradle

ext {
    dependencies = [
            "hilt-android" : "com.google.dagger:hilt-android:2.28-alpha",
            "hilt-android-compiler" : "com.google.dagger:hilt-android-compiler:2.28-alpha"
    ]
}

build.gradle

apply from : "custom.gradle"

buildscript {
    dependencies {
        classpath "com.android.tools.build:gradle:4.2.0"
        // 添加这行
        classpath "com.google.dagger:hilt-android-gradle-plugin:2.28-alpha"
    }
}

mytest1\build.gradle

plugins {
    id 'com.android.application'
}

// 添加这行
apply plugin: "dagger.hilt.android.plugin"

dependencies {
    ......
    // 添加依赖
    implementation rootProject.ext.dependencies["hilt-android"]
    annotationProcessor rootProject.ext.dependencies["hilt-android-compiler"]
}

HttpObject.java

mytest1\src\main\java\com\example\mytest1\obj\HttpObject.java

public class HttpObject {
}

HttpModule.java

mytest1\src\main\java\com\example\mytest1\module\HttpModule.java

import com.example.mytest1.obj.HttpObject;
import javax.inject.Singleton;
import dagger.Module;
import dagger.Provides;
import dagger.hilt.InstallIn;
import dagger.hilt.android.components.ActivityComponent;
import dagger.hilt.android.components.ApplicationComponent;
import dagger.hilt.android.scopes.ActivityScoped;

@InstallIn(ApplicationComponent.class) // 能注入到 Activity，能注入到 Application
//@InstallIn(ActivityComponent.class) // 能注入到 Activity，不能注入到 Application
@Module
public class HttpModule {
    @Provides
    @Singleton // 配合 @InstallIn(ApplicationComponent.class) ，全局单例
//    @ActivityScoped // 配合 @InstallIn(ActivityComponent.class) ，局部单例
    public HttpObject getHttpObject() {
        return new HttpObject();
    }
}

MyApplication

mytest1\src\main\java\com\example\mytest1\MyApplication.java

import android.app.Application;
import dagger.hilt.android.HiltAndroidApp;

@HiltAndroidApp
public class MyApplication extends Application {
}

MainActivity

mytest1\src\main\java\com\example\mytest1\MainActivity.java

import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import com.example.mytest1.obj.HttpObject;
import javax.inject.Inject;
import dagger.hilt.android.AndroidEntryPoint;

@AndroidEntryPoint // 被注入的
public class MainActivity extends AppCompatActivity {
    private static final String TAG = "AAAAAAAAAAA";

    @Inject
    HttpObject httpObject;

    @Inject
    HttpObject httpObject2;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Log.d(TAG, "onCreate: " + httpObject.hashCode());
        Log.d(TAG, "onCreate: " + httpObject2.hashCode());

        findViewById(R.id.test_bt).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(MainActivity.this, MainActivity2.class);
                startActivity(intent);
            }
        });
    }
}

MainActivity2

mytest1\src\main\java\com\example\mytest1\MainActivity2.java

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import com.example.mytest1.obj.HttpObject;
import javax.inject.Inject;
import dagger.hilt.android.AndroidEntryPoint;

@AndroidEntryPoint
public class MainActivity2 extends AppCompatActivity {
    private static final String TAG = "AAAAAAAAAAA";

    @Inject
    HttpObject httpObject;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);

        Log.d(TAG, "onCreate: " + httpObject.hashCode());
    }
}

接口依赖注入

MyApplication

mytest2\src\main\java\com\example\mytest2\MyApplication.java

import android.app.Application;
import dagger.hilt.android.HiltAndroidApp;

@HiltAndroidApp
public class MyApplication extends Application {
}

IHttpRequest接口

mytest2\src\main\java\com\example\mytest2\http\IHttpRequest.java

public interface IHttpRequest {
    void get();
}

HttpRequestImpl

mytest2\src\main\java\com\example\mytest2\http\HttpRequestImpl.java

import android.util.Log;
import javax.inject.Inject;

public class HttpRequestImpl implements IHttpRequest{
    private static final String TAG = "AAAAAAAAAAAAAAAAAA";

    @Inject
    HttpRequestImpl() {}

    @Override
    public void get() {
        Log.d(TAG, "测试接口注入！");
    }
}

HttpRequestModule

mytest2\src\main\java\com\example\mytest2\http\HttpRequestModule.java

import dagger.Binds;
import dagger.Module;
import dagger.hilt.InstallIn;
import dagger.hilt.android.components.ActivityComponent;

@Module
@InstallIn(ActivityComponent.class)
public abstract class HttpRequestModule {
    @Binds
    public abstract IHttpRequest bindTest(HttpRequestImpl httpRequest);
}

MainActivity

mytest2\src\main\java\com\example\mytest2\MainActivity.java

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import com.example.mytest2.http.IHttpRequest;
import javax.inject.Inject;
import dagger.hilt.android.AndroidEntryPoint;

@AndroidEntryPoint
public class MainActivity extends AppCompatActivity {
    @Inject
    IHttpRequest httpRequest;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        httpRequest.get();
    }
}

代码示例

地址：HiltDemo