我刚刚下载并安装了新的Android SDK。我想创建一个简单的应用程序来测试它。

向导创建了以下代码:

package eu.mauriziopz.gps;

import android.app.Activity;
import android.os.Bundle;

public class ggps extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
}

但是Eclipse给出了错误

R不能被分解

在网上

setContentView(R.layout.main);

Why?

PS:我在res/layout/下有一个名为main.xml的XML文件。


当前回答

So I have run into this problem multiple times when switching build targets. Usually doing a Project >> Clean worked for me. This last time, however, it did not. Finally I tried to open my default.properties file, located under the root project folder. I received an error message stating that it was out of sync with the file system. I actually deleted it and copied a coworkers version which allowed eclipse to rebuild my R file. I will paste what it looks like below. It is named 'default.properties'.

# This file is automatically generated by Android Tools.
# Do not modify this file -- YOUR CHANGES WILL BE ERASED!
# 
# This file must be checked in Version Control Systems.
# 
# To customize properties used by the Ant build system use,
# "build.properties", and override values to adapt the script to your
# project structure.

# Indicates whether an apk should be generated for each density.
split.density=false
# Project target.
target=android-3

其他回答

R有两种出错的方式

1)布局文件ie xml文件的问题

2)如果你更新adt,那么就会出现R问题。 -你必须检查项目的属性 - goto->属性->Java构建路径->命令和导出,并检查所有的lib。

这将解决问题。

检查上面的类文件导入,确保没有android的导入。R,如果它有,然后删除它,然后按Ctrl + Shift + o,选择packagename。R不导入另一个。

还有一件事可能会导致这个问题:

我安装了新的ADT(第22节)。它停止创建包含R.java的gen文件夹。解决方案是在Android SDK管理器中安装新的Android SDK构建工具。

在这里找到解决方案

对我来说,这是因为使用了“私人”android drawables:

[2015-11-26 18:59:48 - MyAndroidApp] 
/Users/myname/git/MyAndroidApp/res/menu/drawer_view.xml:24: 
error: Error: Resource is not public. (at 'icon' with value 
'@android:drawable/ic_menu_home').

有趣的是,直到我使用图标删除了对文件的引用,这个错误才出现在控制台中。

android:entries="@menu/drawer_view"

现在解决方案非常明显,将图标复制到我的项目(res/draw - xxxx /)并切换到本地引用。

@drawable/ic_menu_home

希望这能有所帮助。

1)首先关闭所有文件。 2)进入Build ->清洁项目。 3)进入Build ->重建项目。

这对我很有用。