除了@lonkly解决方案

参见反射和现场可访问性 不必要的变量

方法:

/**
 * lookup a resource id by field name in static R.class 
 * 
 * @author - ceph3us
 * @param variableName - name of drawable, e.g R.drawable.<b>image</b>
 * @param с            - class of resource, e.g R.drawable.class or R.raw.class
 * @return integer id of resource
 */
public static int getResId(String variableName, Class<?> с)
                     throws android.content.res.Resources.NotFoundException {
    try {
        // lookup field in class 
        java.lang.reflect.Field field = с.getField(variableName);
        // always set access when using reflections  
        // preventing IllegalAccessException   
        field.setAccessible(true);
        // we can use here also Field.get() and do a cast 
        // receiver reference is null as it's static field 
        return field.getInt(null);
    } catch (Exception e) {
        // rethrow as not found ex
        throw new Resources.NotFoundException(e.getMessage());
    }
}

•Kotlin版本通过扩展功能

在Kotlin中通过名称查找资源id，在Kotlin文件中添加以下代码片段:

ExtensionFunctions.kt

import android.content.Context
import android.content.res.Resources

fun Context.resIdByName(resIdName: String?, resType: String): Int {
    resIdName?.let {
        return resources.getIdentifier(it, resType, packageName)
    }
    throw Resources.NotFoundException()
}

•使用

现在所有的资源id都是可访问的，只要你有一个上下文引用使用resIdByName方法:

val drawableResId = context.resIdByName("ic_edit_black_24dp", "drawable")
val stringResId = context.resIdByName("title_home", "string")
.
.
.    

int resourceID = 
    this.getResources().getIdentifier("resource name", "resource type as mentioned in R.java",this.getPackageName());

我建议您使用我的方法来获取资源ID。它比使用getIdentidier()方法更有效，后者比较慢。

代码如下:

/**
 * @author Lonkly
 * @param variableName - name of drawable, e.g R.drawable.<b>image</b>
 * @param с - class of resource, e.g R.drawable.class or R.raw.class
 * @return integer id of resource
 */
public static int getResId(String variableName, Class<?> с) {

    Field field = null;
    int resId = 0;
    try {
        field = с.getField(variableName);
        try {
            resId = field.getInt(null);
        } catch (Exception e) {
            e.printStackTrace();
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    return resId;

}

如果你需要在compose中这样做，你可以这样做:

val context = LocalContext.current
val drawableId = remember(iconName) {
     //this block will re-calculate each time iconName has changed
     val resId by derivedStateOf {
        context.resources.getIdentifier(
             iconName,
             "drawable",
             context.packageName
            )
        }
    if (resId != 0) resId else R.drawable.some_fallback_icon //it doesn't throw an error instead resId becomes 0, so we need to check if 0 aka couldn't find the drawable.
   }

//然后使用drawableId

like painterResource(id = drawableId)

我发现这个类在处理资源方面非常有用。它有一些定义的方法来处理尺寸，颜色，drawables和字符串，就像这个:

public static String getString(Context context, String stringId) {
    int sid = getStringId(context, stringId);
    if (sid > 0) {
        return context.getResources().getString(sid);
    } else {
        return "";
    }
}