Android JUnit模拟活动上下文

import android.content.Context;
import android.widget.Toast;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mock;
import org.mockito.MockitoAnnotations;
import org.mockito.junit.MockitoJUnitRunner;

import static org.mockito.Mockito.*;

@RunWith(MockitoJUnitRunner.class)
public class ExampleUnitTest {

    @Mock
    private Context mockContext;

    @Test
    public void testToastMessage() {
        // 初始化模拟对象
        MockitoAnnotations.initMocks(this);

        // 创建被测试的对象
        ToastHelper toastHelper = new ToastHelper();

        // 设置模拟对象的行为
        when(mockContext.getString(anyInt())).thenReturn("Mocked Toast Message");

        // 调用被测试的方法
        toastHelper.showToast(mockContext, R.string.toast_message);

        // 验证模拟对象的方法是否被调用
        verify(mockContext).getString(R.string.toast_message);
        verify(mockContext).getSystemService(Context.TOAST_SERVICE);
    }
}

class ToastHelper {
    public void showToast(Context context, int messageId) {
        String message = context.getString(messageId);
        Toast.makeText(context, message, Toast.LENGTH_SHORT).show();
    }
}