android - 如何从主目录访问产品 flavor 类？

Question

我的应用程序中有两种产品 flavor
flavorOne(src/flavorOne/java) 和flavorTwo(src/flavorTwo/java)。 Main (src/main/java) 是两种风格都使用类的目录形式。我想从 src/main/java/ActivityA 中的 Activity 开始 Activity src/flavorTwo/java/ActivityB.java。在运行 flavorTwo 时它可以工作，但是当我切换 flavorOne 时它​​显示导入 com.packagename.ActivityB 错误。

+ App // module
    |- src
       |- main// shared srcDir
          |- java
           |- SharedActivity
       + flavorOne
          |- java
           |- FlavorOneActivity
       + flavorTwo
          |- java
           |- FlavorTwoActivity

这是目录 src/main/java/SharedActivity.java 中的 SharedActivity.java

package com.example.buildvariants;

import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
/**********************  works if it is in flavorOne otherwise it shows error on this package import ***********/
import com.example.buildvariants.flavorOne.LoginActivity;

public class SharedActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);

        //if flavor is flavorTwo hide the fab
        //else flavor is flavorOne show fab and launch activity under flavorOne/java/LoginActivity.java
        if (BuildConfig.FLAVOR.equalsIgnoreCase("flavorTwo")) {
            fab.setVisibility(View.GONE);
        } else {
            fab.setVisibility(View.VISIBLE);
            fab.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                            .setAction("Action", null).show();
                    startActivity(new Intent(SharedActivity.this, LoginActivity.class));

                }
            });
        }
    }
}

flavorOne src/flavorOne/FlavorOneMainActivity.java 下的 Activity

package com.example.buildvariants.flavorOne;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

import com.example.buildvariants.R;
import com.example.buildvariants.SharedActivity;

public class FlavorOneMainActivity extends AppCompatActivity {

    private static final String TAG =FlavorOneMainActivity.class.getSimpleName() ;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.flavor_one_activity_main);
        Intent intent = new Intent(FlavorOneMainActivity.this, SharedActivity.class);
        startActivity(intent);
    }
}

flavorTwo src/flavorOne/FlavorTwoMainActivity.java 下的 Activity

package com.example.buildvariants.flavorTwo;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

import com.example.buildvariants.R;
import com.example.buildvariants.SharedActivity;

public class FlavorTwoMainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.flavor_two_activity_main);
        startActivity(new Intent(FlavorTwoMainActivity.this, SharedActivity.class));
    }
}

当我更改构建变体 flavorTwo 时，SharedActivity(src/main/java/) 的包导入显示错误，如下所示。

package com.example.buildvariants;

import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
/********error  on package import***********/
import com.example.buildvariants.flavorOne.LoginActivity;

public class SharedActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);

        //if flavor is flavorTwo hide the fab
        //else flavor is flavorOne show fab and launch activity under flavorOne/java/LoginActivity.java
        if (BuildConfig.FLAVOR.equalsIgnoreCase("flavorTwo")) {
            fab.setVisibility(View.GONE);
        } else {
            fab.setVisibility(View.VISIBLE);
            fab.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                            .setAction("Action", null).show();
                    startActivity(new Intent(SharedActivity.this, LoginActivity.class));

                }
            });
        }
    }
}

这个问题的最佳解决方案是什么？

Answer 1

它失败了，因为当您构建您的应用程序时，一次只存在一种产品风格的代码。因此，您真正想要做的是在两种产品风格中使用同一个类名。

假设我们有一个类，我们希望根据产品口味替换它，我们称它为 ReplacableActivity.java

要使替换正常工作，两种产品风格都需要有这个类，而主要的源集不会有这个类

例子:

src/main/com/blah/myApp/ReplacableActivity #<- should not exist
# exists and is the implementation of ReplacableActivity for `flavorOne`
src/flavorOne/com/blah/myApp/ReplacableActivity.java
# exists and is the implementation of ReplaceableActivity.java for `flavorTwo`
src/flavorTwo/com/blah/myApp/ReplacableActivity.java

现在，对于您构建的所有产品风格，ReplacableActivity 都存在并且可以从 main 源集中引用。在构建时，只有该特定风格的 ReplaceableActivity 会与应用程序打包在一起。现在您的导入将按预期工作 从 main 源集中导入 com.blah.myApp.ReplaceableActivity;。

编辑:

如果您唯一关心的是隐藏或显示单个元素，那么上面的内容就有点矫枉过正了。从 BuildConfigField

获取它会容易得多

android {
    productFlavors {
        flavorOne {
            buildConfigField "boolean", "flavorShowsFab", 'false'
        }
        flavorTwo {
            buildConfigField 'boolean', 'flavorShowsFab', 'true'
        }
    }

然后在你的java代码中做

findViewById(R.id.myHidableFab).setVisibility(BuildConfig.flavorShowsFab ? View.VISIBLE : View.GONE));