38. Android 反射资源工具ReflectionUtil

工具代码

ReflectionUtil

public class ReflectionUtil {    public enum ResourcesType {        styleable,        style,        string,        mipmap,        menu,        layout,        integer,        id,        drawable,        dimen,        color,        bool,        attr,        anim    }    /**     * 根据名字，反射取得资源     *     * @param context context     * @param name    resources name     * @param type    enum of ResourcesType     * @return resources id     */    public static int getResourceId(Context context, String name, ResourcesType type) {        String className = context.getPackageName() + ".R";        try {            Class<?> c = Class.forName(className);            for (Class childClass : c.getClasses()) {                String simpleName = childClass.getSimpleName();                if (simpleName.equals(type.name())) {                    for (Field field : childClass.getFields()) {                        String fieldName = field.getName();                        if (fieldName.equals(name)) {                            try {                                return (int) field.get(null);                            } catch (IllegalAccessException e) {                                e.printStackTrace();                            }                        }                    }                }            }        } catch (ClassNotFoundException e) {            e.printStackTrace();        }        return -1;    }}

工具使用

ReflectionUtilActivity

public class ReflectionUtilActivity extends AppCompatActivity implements View.OnClickListener {    ImageView imageView;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        this.setContentView(R.layout.activity_reflection_util);        this.imageView = (ImageView) this.findViewById(R.id.reflection_iv);        this.findViewById(R.id.reflection_bt).setOnClickListener(this);    }    /**     * Called when a view has been clicked.     *     * @param v The view that was clicked.     */    @Override    public void onClick(View v) {        switch (v.getId()) {            case R.id.reflection_bt:                /*                 * 获取资源名为mm_1的mipmap类型文件                 */                this.imageView.setImageResource(ReflectionUtil.getResourceId(this, "mm_1", ReflectionUtil.ResourcesType.mipmap));                break;        }    }}