Android ApiDemos示例解析(48)：Content->Resources->Resources

Android SDK对应没个定义在res目录下的资源都会定义一个维一的资源ID。在编译时会在gen目录下生成 R.java , 资源ID的格式为 R.[type].[id] 类型为资源类型如anim, array, attr等

可以在代码或是XML资源文件(如layout, style中）访问这些资源。

Context类提供了访问资源的方法，一是直接通过如getText, getString等来访问资源，此外一般的方法是通过getResources()来取代Resources对象，再通过Resources对象来访问资源。下图为Context的类继承图：

可以看到Application ,Service ,Activity 都是Context的子类，因此在这些类中都可以直接访问资源：

// Using the getString() conevenience method, // retrieve a string // resource that hapepns to have style information. //Note the use of // CharSequence instead of String so we don't // lose the style info. cs = getText(R.string.styled_text); tv = (TextView)findViewById(R.id.styled_text); tv.setText(cs);   // Use the same resource, but convert it to a //string, which causes it // to lose the style information. str = getString(R.string.styled_text); tv = (TextView)findViewById(R.id.plain_text); tv.setText(str);   // You might need to do this if your code // is not in an activity. // For example View has a protected mContext //field you can use. // In this case it's just 'this' since //Activity is a context. Context context = this;   // Get the Resources object from our context Resources res = context.getResources();   // Get the string resource, like above. cs = res.getText(R.string.styled_text); tv = (TextView)findViewById(R.id.res1); tv.setText(cs);