为什么要做activity的管理
在android app的开发过程中，或多或少会涉及到activity的管理。会有这样的业务场景存在，例如：
- 广播接收器接收到某个动作，需要finish某个指定的activity；
- 在缺乏activity上下文的地方也需要finish某个指定的activity......
话不多说，上代码。
1. AppManager.java
/**
* ProjectName：AndroidUtil
* PackageName: com.standard.util.helper
* Description：自定义activity的栈管理(栈结构扩展Vector，元素不要求唯一性，可存在多个相同实例)
*
* CreateTime: 6/24/2016 12:36
* Modifier：liminghuang
* ModifyTime：6/24/2016 12:36
* Comment：因为第一版本AppManager的使用过程中发现存在问题，所以为了保持api的一致性，采用桥接模式委托AppManagerDelegate类处理
*
* @author liminghuang
*/
public final class AppManager {
/** 是否使用桥接模式 **/
private boolean isBridge = false;
/** AppManager管理activity的委托类 **/
private AppManagerDelegate mDelegate;
/** 维护activity的栈结构 **/
private Stack mActivityStack;
private static volatile AppManager sInstance;
/**
* 隐藏构造器
*
* @param isBridge 是否开启桥接模式
*/
private AppManager(boolean isBridge) {
this.isBridge = isBridge;
mDelegate = AppManagerDelegate.getInstance();
}
/**
* 单例
*
* @return 返回AppManager的单例
*/
public static AppManager getInstance() {
if (sInstance == null) {
synchronized (AppManager.class) {
if (sInstance == null) {
sInstance = new AppManager(true);
}
}
}
return sInstance;
}
/**
* 添加Activity到堆栈
*
* @param activity activity实例
*/
public void addActivity(Activity activity) {
if (isBridge) {
mDelegate.addActivity(activity);
} else {
if (mActivityStack == null) {
mActivityStack = new Stack<>();
}
mActivityStack.add(activity);
}
}
/**
* 获取当前Activity（栈中最后一个压入的）
*
* @return 当前（栈顶）activity
*/
public Activity currentActivity() {
if (isBridge) {
return mDelegate.currentActivity();
} else {
if (mActivityStack != null && !mActivityStack.isEmpty()) {
return mActivityStack.lastElement();
}
return null;
}
}
/**
* 结束除当前activtiy以外的所有activity
* 注意：不能使用foreach遍历并发删除，会抛出java.util.ConcurrentModificationException的异常
*
* @param activity 不需要结束的activity
*/
public void finishOtherActivity(Activity activity) {
if (isBridge) {
mDelegate.finishOtherActivity(activity);
} else {
if (mActivityStack != null) {
for (Iterator it = mActivityStack.iterator(); it.hasNext(); ) {
Activity temp = it.next();
if (temp != null && temp != activity) {
finishActivity(temp);
}
}
}
}
}
/**
* 结束除这一类activtiy以外的所有activity
* 注意：不能使用foreach遍历并发删除，会抛出java.util.ConcurrentModificationException的异常
*
* @param cls 不需要结束的activity
*/
public void finishOtherActivity(Class cls) {
if (isBridge) {
mDelegate.finishOtherActivity(cls);
} else {
if (mActivityStack != null) {
for (Iterator it = mActivityStack.iterator(); it.hasNext(); ) {
Activity activity = it.next();
if (!activity.getClass().equals(cls)) {
finishActivity(activity);
}
}
}
}
}
/**
* 结束当前Activity（堆栈中最后一个压入的）
*/
public void finishActivity() {
if (isBridge) {
mDelegate.finishActivity();
} else {
if (mActivityStack != null && !mActivityStack.isEmpty()) {
Activity activity = mActivityStack.lastElement();
finishActivity(activity);
}
}
}
/**
* 结束指定的Activity
*
* @param activity 指定的activity实例
*/
public void finishActivity(Activity activity) {
if (isBridge) {
mDelegate.finishActivity(activity);
} else {
if (activity != null) {
if (mActivityStack != null && mActivityStack.contains(activity)) {// 兼容未使用AppManager管理的实例
mActivityStack.remove(activity);
}
activity.finish();
}
}
}
/**
* 结束指定类名的所有Activity
*
* @param cls 指定的类的class
*/
public void finishActivity(Class cls) {
if (isBridge) {
mDelegate.finishActivity(cls);
} else {
if (mActivityStack != null) {
for (Iterator it = mActivityStack.iterator(); it.hasNext(); ) {
Activity activity = it.next();
if (activity.getClass().equals(cls)) {
finishActivity(activity);
}
}
}
}
}
/**
* 结束所有Activity
*/
public void finishAllActivity() {
if (isBridge) {
mDelegate.finishAllActivity();
} else {
if (mActivityStack != null) {
for (int i = 0, size = mActivityStack.size(); i < size; i++) {
if (null != mActivityStack.get(i)) {
mActivityStack.get(i).finish();
}
}
mActivityStack.clear();
}
}
}
/**
* 退出应用程序
*/
public void exitApp() {
if (isBridge) {
mDelegate.exitApp();
} else {
try {
finishAllActivity();
// 退出JVM(java虚拟机),释放所占内存资源,0表示正常退出(非0的都为异常退出)
System.exit(0);
// 从操作系统中结束掉当前程序的进程
android.os.Process.killProcess(android.os.Process.myPid());
} catch (Exception e) {
LogUtil.e("Exit exception", e);
}
}
}
}
2. AppManagerDelegate.java
/**
* ProjectName：AndroidUtil
* PackageName: com.standard.util.helper
* Description：自定义activity的栈管理(栈结构扩展Vector，元素不要求唯一性，可存在多个相同实例)
*
* CreateTime: 6/24/2016 12:36
* Modifier：liminghuang
* ModifyTime：6/24/2016 12:36
* Comment：
*
* @author liminghuang
*/
public final class AppManagerDelegate {
// 使用弱引用是因为存在未使用AppManager的finish方法来释放的activity，但mActivityStack并未断开对其应用导致内存泄露的问题
private Stack> mActivityStack;
private static volatile AppManagerDelegate sInstance;
private AppManagerDelegate() {
}
/**
* 单例
*
* @return 返回AppManager的单例
*/
public static AppManagerDelegate getInstance() {
if (sInstance == null) {
synchronized (AppManagerDelegate.class) {
if (sInstance == null) {
sInstance = new AppManagerDelegate();
}
}
}
return sInstance;
}
/**
* 添加Activity到堆栈
*
* @param activity activity实例
*/
public void addActivity(Activity activity) {
if (mActivityStack == null) {
mActivityStack = new Stack<>();
}
mActivityStack.add(new WeakReference<>(activity));
}
/**
* 检查弱引用是否释放，若释放，则从栈中清理掉该元素
*/
public void checkWeakReference() {
if (mActivityStack != null) {
for (Iterator> it = mActivityStack.iterator(); it.hasNext(); ) {
WeakReference activityReference = it.next();
Activity temp = activityReference.get();
if (temp == null) {
it.remove();// 使用迭代器来进行安全的加锁操作
}
}
}
}
/**
* 获取当前Activity（栈中最后一个压入的）
*
* @return 当前（栈顶）activity
*/
public Activity currentActivity() {
checkWeakReference();
if (mActivityStack != null && !mActivityStack.isEmpty()) {
return mActivityStack.lastElement().get();
}
return null;
}
/**
* 结束除当前activtiy以外的所有activity
* 注意：不能使用foreach遍历并发删除，会抛出java.util.ConcurrentModificationException的异常
*
* @param activtiy 不需要结束的activity
*/
public void finishOtherActivity(Activity activtiy) {
if (mActivityStack != null && activtiy != null) {
for (Iterator> it = mActivityStack.iterator(); it.hasNext(); ) {
WeakReference activityReference = it.next();
Activity temp = activityReference.get();
if (temp == null) {// 清理掉已经释放的activity
it.remove();
continue;
}
if (temp != activtiy) {
it.remove();// 使用迭代器来进行安全的加锁操作
temp.finish();
}
}
}
}
/**
* 结束除这一类activtiy以外的所有activity
*
* @param cls 指定的某类activity
*/
public void finishOtherActivity(Class cls) {
if (mActivityStack != null) {
for (Iterator> it = mActivityStack.iterator(); it.hasNext(); ) {
WeakReference activityReference = it.next();
Activity activity = activityReference.get();
if (activity == null) {// 清理掉已经释放的activity
it.remove();
continue;
}
if (!activity.getClass().equals(cls)) {
it.remove();// 使用迭代器来进行安全的加锁操作
activity.finish();
}
}
}
}
/**
* 结束当前Activity（堆栈中最后一个压入的）
*/
public void finishActivity() {
Activity activity = currentActivity();
if (activity != null) {
finishActivity(activity);
}
}
/**
* 结束指定的Activity
*
* @param activity 指定的activity实例
*/
public void finishActivity(Activity activity) {
if (activity != null) {
for (Iterator> it = mActivityStack.iterator(); it.hasNext(); ) {
WeakReference activityReference = it.next();
Activity temp = activityReference.get();
if (temp == null) {// 清理掉已经释放的activity
it.remove();
continue;
}
if (temp == activity) {
it.remove();
}
}
activity.finish();
}
}
/**
* 结束指定类名的所有Activity
*
* @param cls 指定的类的class
*/
public void finishActivity(Class cls) {
if (mActivityStack != null) {
for (Iterator> it = mActivityStack.iterator(); it.hasNext(); ) {
WeakReference activityReference = it.next();
Activity activity = activityReference.get();
if (activity == null) {// 清理掉已经释放的activity
it.remove();
continue;
}
if (activity.getClass().equals(cls)) {
it.remove();
activity.finish();
}
}
}
}
/**
* 结束所有Activity
*/
public void finishAllActivity() {
if (mActivityStack != null) {
for (Iterator> it = mActivityStack.iterator(); it.hasNext(); ) {
WeakReference activityReference = it.next();
Activity activity = activityReference.get();
if (activity != null) {
activity.finish();
}
}
mActivityStack.clear();
}
}
/**
* 退出应用程序
*/
public void exitApp() {
try {
finishAllActivity();
// 退出JVM(java虚拟机),释放所占内存资源,0表示正常退出(非0的都为异常退出)
System.exit(0);
// 从操作系统中结束掉当前程序的进程
android.os.Process.killProcess(android.os.Process.myPid());
} catch (Exception e) {
LogUtil.e("Exit exception", e);
}
}
}
如何使用
- 在BaseActivity#onCreate回调中添加AppManager.getInstance().addActivity(this)
- 获取当前栈顶activityAppManager.getInstance().currentActivity()
- 在需要销毁的当前activity的地方调用AppManager.getInstance().finishActivity()
- 在需要销毁指定类别实例的地方调用AppManager.getInstance().finishActivity(XXX.class)
- 在需要销毁指定类别除外的其他实例的地方调用AppManager.getInstance().finishOtherActivity(XXX.class)
- 退出应用调用AppManager.getInstance().exitApp()