static const int var = 5; #define var 5 enum { var = 5 }; 回答 取决于你用来干什么。...static const int var = 5 #define var 5 enum { var = 5 } 如果需要传指针,那只能用 (1) (1) 不能作为全局作用域下数组的维数定义,而 (2)(...) 不能在 switch 语句下使用,而 (2)(3) 可以 (1) 不能用来初始化另一个静态常量,而 (2)(3) 可以 (2) 可以用预处理器判断是否已存在,而 (1)(3) 不可以 大多场景下,enum
; flags: ACC_PUBLIC, ACC_STATIC, ACC_FINAL, ACC_ENUM public static final club.throwable.enumeration.PhoneOsEnum...; private final String typeName; public static final PhoneOsEnumeration ANDROID; public static final...PhoneOsEnumeration IOS; private static final PhoneOsEnumeration[] $VALUES; static { ANDROID = new...protected Enum(String name, int ordinal),其他方法的实现都是十分简单。...return name; } private final int ordinal; public final int ordinal() { return
public static final Color BLACK; public static final Color WHITE; // private static final...Enum成员变量和方法分析 Enum类实现了 Comparable接口,表明它是支持排序的,可以通过 Collections.sort 进行自动排序.实现了public final int compareTo...public final int compareTo(E o) { Enum other = (EnumAndroid. 使用枚举常量比使用final static来实现常量定义,枚举的内存消耗比后高不止两倍....单个枚举类型常量,比static final声明的常量占用的内存大的多. 因此,不建议在Android中使用枚举常量,而更偏向于使用 static final来定义常量.
. public static final int COLOR_RED = 0; public static final int COLOR_GREEN = 1; public static final...java.lang.enum的类 既然隐式继承自java.lang.enum,也就意味java代码中,Season不能再继承其他的类 Season被标记成了final,意味着它不能被继承 static代码块...转成了int值(通过调用Enum.oridinal()方法) 枚举与混淆 在Android开发中,进行混淆是我们在发布前必不可少的工作,混下后,我们能增强反编译的难度,在一定程度上保护了增强了安全性....关于枚举是否使用的结论,大家可以参考 如果你开发的是Framework不建议使用enum 如果是简单的enum,可以使用int很轻松代替,则不建议使用enum 另外,如果是Android中,可以使用下面介绍的枚举注解来实现...final int RED = 0; public static final int GREEN = 1; public static final int YELLOW = 2; }
. public static final int COLOR_RED = 0;public static final int COLOR_GREEN = 1;public static final int...SPRING; public static final com.company.Season SUMMER; public static final com.company.Season AUTUMN...转成了int值(通过调用Enum.oridinal()方法) 枚举与混淆 在Android开发中,进行混淆是我们在发布前必不可少的工作,混下后,我们能增强反编译的难度,在一定程度上保护了增强了安全性....关于枚举是否使用的结论,大家可以参考 如果你开发的是Framework不建议使用enum 如果是简单的enum,可以使用int很轻松代替,则不建议使用enum 另外,如果是Android中,可以使用下面介绍的枚举注解来实现...final int RED = 0; public static final int GREEN = 1; public static final int YELLOW = 2; } 声明必要的
public class TriangleView extends View { private static final int TOP = 0; private static final...int BOTTOM = 1; private static final int RIGHT = 2; private static final int LEFT = 3; private...static final int DEFUALT_WIDTH = 10; private static final int DEFUALT_HEIGHT = 6; private static...final int DEFUALT_COLOR = R.color.FFF; private Paint mPaint; private int mColor; private...Context context, final AttributeSet attrs, final int defStyleAttr) { super(context, attrs, defStyleAttr
final int VIEW_CONTENT = 0; // 加载 View public static final int VIEW_LOADING = -1; // 数据异常...( 数据异常指原本应该是有数据,但是服务器返回了错误的、不符合格式的数据 ) View public static final int VIEW_ERROR_DATA = -2; //...网络异常 View public static final int VIEW_ERROR_NET = -3; // 数据为空 View public static final int...VIEW_EMPTY = -4; // View 的 Tag 标签值 private static final int VIEW_TAG = -5; // 用来存放 View...int state, final View showView, final View currentView) { ObjectAnimator
> componentType, int… dimensions) 指定组件类型和多个固定长度创建多维数组,维度的最大值为255 static native int getLength(Object array...2、所有的枚举成员属性都变成static final修饰的在第1步中提到的Java类的实例,属性的名称和原来枚举的名字一致,实例在静态代码块中创建。...; private final String typeName; public static final PhoneOsEnumeration ANDROID; public static final...PhoneOsEnumeration IOS; private static final PhoneOsEnumeration[] $VALUES; static { ANDROID = new...$VALUES = new PhoneOsEnumeration[]{ANDROID, IOS}; } } 实际上,如果你直接编写一个Java类去继承java.lang.Enum会编译报错,也就是
于是我就写了一个简单的程序来告诉他们,伪代码如下: public final static int DAVID = 0; public final static int MARRY = 1; public...相比使用 int 常量来定义,枚举具有类型安全和可读性良好的优势。《Effective Java》中也鼓励 用 enum 代替 int 常量。...int compareTo(E o) { Enum<?...} public static final Child DAVID; public static final Child MARY; private String name...枚举中声明的变量都是 static final 的,且在 static 代码块中进行初始化,并存入对象数组 VALUES。所以枚举实例的创建默认是线程安全的。
> { public static final com.example.admin.proguardsample.Day MONDAY; public static final com.example.admin.proguardsample.Day...TUESDAY; public static final com.example.admin.proguardsample.Day WEDNESDAY; public static final...com.example.admin.proguardsample.Day THURSDAY; public static final com.example.admin.proguardsample.Day...FRIDAY; public static final com.example.admin.proguardsample.Day SATURDAY; public static final com.example.admin.proguardsample.Day...valueOf(java.lang.String); static {}; } 枚举实际是创建了一个继承自java.lang.Enum的类 java代码中的枚举类型最后转换成类中的static
可以定义轮播图的圆点样式 核心代码 public class FlashView extends RelativeLayout { private static final int RMP...= LayoutParams.MATCH_PARENT; private static final int RWP = LayoutParams.WRAP_CONTENT; private...static final int LWC = LinearLayout.LayoutParams.WRAP_CONTENT; private static final int WHAT_AUTO_PLAY...= 1000; //Point位置 public static final int CENTER = 0; public static final int LEFT = 1;...public static final int RIGHT = 2; private LinearLayout mPointRealContainerLl; private
sdk自带attrs.xml 我们可以看到除了通常定义的attr,还要在attr结点的节点内部添加enum常量。...ScaleView"> enum...> 自定义控件java实现 public class ScaleImageView extends ImageView { // 常量标记:固定宽度 public static final...int SOLID_WIDTH = -1; // 常量标记:固定高度 public static final int SOLID_HEIGHT = -2; // 常量标记...:未设置比例 private static final float NO_SCALE = -1; // 宽高比 private float mScale = NO_SCALE
static final Boolean TRUE = new Boolean(true); public static final Boolean FALSE = new Boolean(false...29、优先考虑类型安全的异构容器 30、用enum代替int常量 public enum Apple { FUJI, PIPPIN, GRANNY_SMITH } public enum Orange...32、用EnumSet代替位域 public class Text{ public static final int STYLE_BOLD = 1 << 0; // 1 public static...final int STYLE_ITALIC = 1 << 1; // 2 public static final int STYLE_UNDERLINE = 1 static final int STYLE_STRIKETHROUGH = 1 << 3; // 8 public void applyStyles(int styles){
private static final java.io.ObjectStreamField[] serialPersistentFields; private void writeObject...enum * { public static **[] values(); public static ** valueOf(java.lang.String); } -keep public..., android.util.AttributeSet, int); } -keepclasseswithmembers class * { public (android.content.Context..., android.util.AttributeSet); public (android.content.Context, android.util.AttributeSet, int...); } -keep class * implements android.os.Parcelable { public static final android.os.Parcelable$Creator
static int OUT_SLIDE_TOP = 0; public final static int OUT_SLIDE_BOTTOM = 1; public final static...int OUT_SLIDE_LEFT = 2; public final static int OUT_SLIDE_RIGHT = 3; @IntDef({OUT_SLIDE_TOP...static long DEFAULT_DRAW_INTERVALS_TIME = 5L; public long DEFAULT_DRAW_INTERVALS_TIME = 100L;.../> enum name="ordinary" value="3" /> enum name="fast" value="5" /> ...value="0" /> enum name="toBottom" value="1" /> enum name="toLeft" value="2" />
mTriangleWidth; private int mTriangleHeight; private static final float RADIO_TRIANGLE_WIDTH...= 1 / 6F; private final int DIMENSION_TRIANGLE_WIDTH_MAX = (int) (getScreenWidth() / 3 * RADIO_TRIANGLE_WIDTH...; private static final int COUNT_DEFAULT_TAB = 4; private static final int COLOR_TEXT_NORMAL...= 0xFF2C2C2C; private static final int COLOR_TEXT_HIGHLIGHT = 0xFF4CAF50; private ViewPager mViewPager...cCount = getChildCount(); for (int i = 0; i < cCount; i++) { final int j = i;
是用的这种东西吗 private final String[] PERMISSIONS = {"android.permission.BLUETOOTH", "android.permission.BLUETOOTH_ADMIN...final SparseArrayCompat h = new SparseArrayCompat(); public final int value;...final String[] a = {"HUAWEI ANE", "HONOR STF"}; static f a() { String upperCase = String.format...int a = 0; private final int b = 1; private final int c = 3; private int d = 0; private...i2, int i3, int i4, int i5) { } private static boolean a(int i2) { if (!
Random random = new Random(47); static final int SIZE = 20; /** * 随机生产 * @return...public static void main(String[] args) { //随机生成20次记录 for (int i = 0; i < SIZE; i...(b)); } public static Enum & Competitor> void play(Class rsbClass, int size...) { for (int i = 0; i < size; i++) { //随机获取枚举值,并比较 match(Enums.random...Random rand = new Random(47); public static Enum> T random(Class ec) {
public static final android.os.Parcelable$Creator CREATOR; } -keepclassmembers class **.R$* {...* implements java.io.Serializable { static final long serialVersionUID; private static final...implements android.os.Parcelable { public static final android.os.Parcelable$Creator *; } #// natvie...{ public static final android.os.Parcelable$Creator *; } #---------------------------------------...final int *; } -keepclassmembers class * { public (org.json.JSONObject); } -keepclassmembers
static final Boolean TRUE = new Boolean(true); public static final Boolean FALSE = new Boolean(false...// 非Android中的AlertDialog,便于说明问题,举个例子 public class AlertDialog { private int width; private int...29、优先考虑类型安全的异构容器 30、用enum代替int常量 public enum Apple { FUJI, PIPPIN, GRANNY_SMITH } public enum Orange ...0; // 1 public static final int STYLE_ITALIC = 1 << 1; // 2 public static... final int STYLE_UNDERLINE = 1 << 2; // 4 public static final int STYLE_STRIKETHROUGH