1. 对话保持的解决方案。
要求:
1、app中使用webview访问具体网站的内容,但是app与服务器的沟通是使用HttpUrlConnection来完成。
2、webview访问时不需要再次登陆,继承app的登陆状态。
会话未保持的现象:
1、虽然app已经登录服务器,但是在webview中还是提示需要登录。
2、app下一次对服务器的请求也会失败,提示session过期。
解决方案:
1、获取到HttpUrlConnection中服务器返回的session id。
2、本地保存session id,每次对服务器的请求,手动添加。
3、将此session id设置到持有webview的activity中的CookieManager里
1 网络处理类 NetHelper
2
3 /**
4 * 发送登陆请求,并将SESSIONID保存起来
5 * @param urlPath 登陆请求的地址
6 * @return 返回的内容
7 * */
8 public static String login(String urlPath) {
9
10 ......省略号......
11
12 try {
13 URL url = new URL(urlPath);
14 HttpURLConnection conn = (HttpURLConnection) url.openConnection();
15
16 //设置请求方式
17 conn.setRequestMethod("GET");
18 conn.setConnectTimeout(5000);
19 // conn.setReadTimeout(5000);
20
21 int responseCode = conn.getResponseCode();
22 if (responseCode == HttpURLConnection.HTTP_OK) {
23 InputStream is = conn.getInputStream();
24 cookList = conn.getHeaderFields().get("Set-Cookie");
25 if ((sessionId == null) && (cookList != null)) {
26 for (String value : cookList) {
27 if ((value != null) && (value.toUpperCase().indexOf(";") > 0)) {
28 sessionId = value.split(";")[0];
29 }
30 }
31 }
32
33 ......省略号......
34
35 }
36 }catch (Exception e){
37 e.printStackTrace();
38 }
39 ......省略号......
40 }/**
41 * 发送一条请求,将内容以字符串返回
42 * @param urlPath 请求的地址
43 * @return 返回的内容
44 * */
45 public static String request(String urlPath) {
46
47 ......省略号......
48
49 try {
50 URL url = new URL(urlPath);
51 HttpURLConnection conn = (HttpURLConnection) url.openConnection();
52 if(sessionId !=null ){
53 conn.setRequestProperty("Cookie",sessionId);
54 }
55 conn.setRequestMethod("GET");
56 conn.setConnectTimeout(5000);
57 // conn.setReadTimeout(5000);
58
59 ......省略号......
60
61 } catch (Exception e) {
62 e.printStackTrace();
63 }
64
65 ......省略号......
66
67 }持有webview的Activity MainActivity
68
69 private CookieManager cookieManager;
70
71 cookieManager = CookieManager.getInstance();
72 cookieManager.setAcceptCookie(true);
73 clearSession();
74
75 private void clearSession() {
76 if (NetHelper.cookList != null) {
77 cookieManager.removeSessionCookie();
78 }
79 }
80
81 //在第一次请求的时候,设置一次session即可
82 private void setSession(String url) {
83 if (NetHelper.cookList != null) {
84 String values = NetHelper.cookList.toString();
85 cookieManager.setCookie(url, values); //设置cookie
86 CookieSyncManager.getInstance().sync(); //同步
87 }
88 }
2. 自定义控件的实现方案
自定义控件的实现方式(详细内容可以参考压缩包中的<自定义控件.pdf>):
1、继承方式
当简单控件不满足需求时,通过继承重写简单控件,实现对控件的定制。
2、组合方式
当单个控件不满足需求时,可以采用多个控件的组合,实现对控件的定制。
3、控件自绘方式
通过继承自view,重写onDraw方法实现。
项目中的具体应用:
1、登录邮箱的自动补全功能实现(纯代码实现布局)。
2、弹窗滚轮的实现(代码加布局文件)
3、TabButton的实现(两种实现方式)
A、 登录邮箱的自动补全功能实现:
效果:
实现原理:
1、继承重写简单控件AutoCompleteTextView
2、编写自定义数据适配器和布局文件,并实现文字变化监听器
3、通过组合方式,实现右侧的删除图标。并根据焦点和文字的变化,动态显示右侧删除图标。
1、通过继承自简单控件AutoCompleteTextView实现帐号自动补全
关键代码:
1 public class AutoComplete extends AutoCompleteTextView {
2
3 private static final String[] emailSuffix = {
4 "@qq.com", "@163.com", "@126.com", "@gmail.com", "@sina.com", "@hotmail.com",
5 "@yahoo.cn", "@sohu.com", "@foxmail.com", "@139.com", "@yeah.net", "@vip.qq.com",
6 "@vip.sina.com"};
7
8 ......省略号......
9
10 //构造函数原型要正确,留给系统调用
11
12 public AutoComplete(Context context) {
13 super(context);
14 mContext = context;
15 }
16
17 public AutoComplete(Context context, AttributeSet attrs) {
18 super(context, attrs);
19 mContext = context;
20 }
21
22 public void init(ImageView imageView) {
23 mImageView = imageView;
24 final MyAdatper adapter = new MyAdatper(mContext);
25 setAdapter(adapter);
26 addTextChangedListener(new TextWatcher() {
27 @Override
28 public void afterTextChanged(Editable s) {
29 if (isTextWatch) {
30 String input = s.toString();
31
32 ......省略号......
33
34 adapter.clearList(); //注意要清空数据,根据输入的变化,自动生成数据
35 if (input.length() > 0) {
36 for (int i = 0; i < emailSuffix.length; ++i) {
37 adapter.addListData(input + emailSuffix[i]);
38 }
39 }
40 adapter.notifyDataSetChanged();
41 showDropDown();//该行代码会造成崩溃
42 }
43 }
44 });
45 //当输入一个字符的时候就开始检测
46 setThreshold(1);
47 }
48
49 private class ViewHolder {
50 TextView tv_Text;
51 }
52
53 class MyAdatper extends BaseAdapter implements Filterable {
54 private List<String> mList;
55 private Context mContext;
56 private MyFilter mFilter;
57
58 ......省略号......
59
60 public void clearList() {
61 mList.clear();
62 }
63
64 public void addListData(String strData) {
65 mList.add(strData);
66 }
67
68 @Override
69 public View getView(int position, View convertView, ViewGroup parent) {
70 View view;
71 ViewHolder viewHolder;
72
73 if (convertView == null) {
74 view = LayoutInflater.from(mContext).inflate(R.layout.activity_autocomplete_item, null);
75 viewHolder = new ViewHolder();
76 viewHolder.tv_Text = (TextView) view.findViewById(R.id.tv_autocomplete);
77 view.setTag(viewHolder);
78 } else {
79 view = convertView;
80 viewHolder = (ViewHolder) view.getTag();
81 }
82
83 viewHolder.tv_Text.setText(mList.get(position));
84
85 return view;
86 }
87
88 ......省略号......
89
90 }
activity_autocomplete_item 下拉列表布局文件
1 <?xml version="1.0" encoding="utf-8"?>
2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
3 android:orientation="vertical"
4 android:layout_width="match_parent"
5 android:background="@color/White"
6 android:layout_height="wrap_content">
7
8 <TextView
9 android:id="@+id/tv_autocomplete"
10 android:padding="15dp"
11 android:textSize="20sp"
12 android:singleLine="true"
13 android:textColor="@color/Black"
14 android:layout_width="match_parent"
15 android:layout_height="wrap_content" />
16
17 </LinearLayout>
上面自动补全的效果图:
2、通过组合方式实现帐号自动补全复杂控件
关键代码:
1 public class AdvancedAutoCompleteTextView extends RelativeLayout {
2 private Context mContext;
3 private AutoComplete mAutoComplete; //上面的自定义控件
4 private ImageView mImageView; //右侧的图标控件
5
6 ......省略号......
7
8 @Override
9 protected void onFinishInflate() {
10 super.onFinishInflate();
11 initViews();
12 }
13 //代码方式,初始化布局
14 private void initViews() {
15 RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT);
16 params.addRule(RelativeLayout.ALIGN_PARENT_LEFT);
17 params.addRule(RelativeLayout.CENTER_VERTICAL);
18 mAutoComplete = new AutoComplete(mContext);
19 mAutoComplete.setLayoutParams(params);
20 mAutoComplete.setPadding(0, 0, 40, 0);
21 mAutoComplete.setSingleLine(true);
22 mAutoComplete.setInputType(InputType.TYPE_TEXT_VARIATION_EMAIL_ADDRESS);
23 mAutoComplete.setFitsSystemWindows(true);
24 mAutoComplete.setEms(10);
25 mAutoComplete.setHint("URS账号");
26 mAutoComplete.setImeOptions(EditorInfo.IME_ACTION_NEXT
27 | EditorInfo.IME_FLAG_NO_EXTRACT_UI | EditorInfo.IME_FLAG_NO_FULLSCREEN);
28 mAutoComplete.setDropDownHorizontalOffset(0);
29 mAutoComplete.setDropDownVerticalOffset(2);
30 mAutoComplete.setBackgroundResource(R.drawable.edit_text_background);
31
32 RelativeLayout.LayoutParams p = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, LayoutParams.FILL_PARENT);
33 p.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);
34 p.addRule(RelativeLayout.CENTER_VERTICAL);
35 p.rightMargin = 10;
36 mImageView = new ImageView(mContext);
37 mImageView.setLayoutParams(p);
38 mImageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
39 mImageView.setImageResource(R.drawable.unselect);
40 mImageView.setClickable(true);
41 mImageView.setOnClickListener(new View.OnClickListener() {
42 @Override
43 public void onClick(View v) {
44 setText("");
45 }
46 });
47
48 this.addView(mAutoComplete);
49 this.addView(mImageView);
50 //监听获取焦点事件,目的:输入帐号时,右侧图标的显示
51 mAutoComplete.setOnFocusChangeListener(new OnFocusChangeListener() {
52 @Override
53 public void onFocusChange(View v, boolean hasFocus) {
54 if (hasFocus && !mAutoComplete.getText().toString().isEmpty()) {
55 mAutoComplete.setShow(false); //如果获取首次获取焦点,此时文本不为空,则显示,并禁止文本改变监听里的设置
56 mImageView.setImageResource(R.drawable.item_delete);
57 } else if (hasFocus) {
58 mAutoComplete.setShow(true);//如果获取首次获取焦点,此时文本为空,则不改变,并开启文本改变监听里的设置
59 } else {
60 mAutoComplete.setShow(false);
61 mImageView.setImageResource(R.drawable.unselect);
62 }
63 }
64 });
65
66 //对AutoComplete自定义控件初始化,一定要放到最后.否则,会由于AutoComplete初始化未完成,就弹窗,而崩溃
67
68 mAutoComplete.init(mImageView);
69 }
70 }
B、弹窗滚轮的实现
效果:
实现原理:
1、继承重写简单控件ScrollView,实现滚动效果,并添加回调接口,用于获取选择的内容。
2、为自定义控件添加内容,其中每一项为一个TextView,用于内容显示。
3、通过自绘添加上下两条直线,实现选中状态。
4、最后利用popup弹窗,加载整个视图,显示弹窗滚动效果。
1、通过继承ScrollView实现滚动,并向布局添加具体项
关键代码:
1 ublic class WheelView extends ScrollView {
2
3 //选择后的回调接口
4 public interface OnWheelViewListener {
5 void onSelected(int selectedIndex, String item);
6 }
7
8 ......省略号......
9
10 //初始化,并创建布局
11 private void init(Context context) {
12 this.context = context;
13 this.setVerticalScrollBarEnabled(false);
14
15 views = new LinearLayout(context); //为自定义控件创建线性布局
16 views.setOrientation(LinearLayout.VERTICAL);
17 this.addView(views);
18
19 //异步任务,根据滚动的位置自动调整待显示的数据,该异步任务会在滚动事件触发式执行
20 scrollerTask = new Runnable() {
21 public void run() {
22 if (itemHeight == 0) {
23 return;
24 }
25 int newY = getScrollY();
26 if (initialY - newY == 0) { // stopped
27 final int remainder = initialY % itemHeight;
28 final int divided = initialY / itemHeight;
29
30 if (remainder == 0) {
31 selectedIndex = divided + offset;
32 onSeletedCallBack();
33 } else {
34 if (remainder > itemHeight / 2) {
35 WheelView.this.post(new Runnable() {
36 @Override
37 public void run() {
38 WheelView.this.smoothScrollTo(0, initialY - remainder + itemHeight);
39 selectedIndex = divided + offset + 1;
40 onSeletedCallBack();
41 }
42 });
43 } else {
44 WheelView.this.post(new Runnable() {
45 @Override
46 public void run() {
47 WheelView.this.smoothScrollTo(0, initialY - remainder);
48 selectedIndex = divided + offset;
49 onSeletedCallBack();
50 }
51 });
52 }
53 }
54 } else {
55 initialY = getScrollY();
56 WheelView.this.postDelayed(scrollerTask, newCheck);
57 }
58 }
59 };
60 }
61
62 //往布局添加数据
63
64 private void initData() {
65 displayItemCount = offset * 2 + 1;
66
67 //添加新view之前,必须移除旧的,否则不正确
68 views.removeAllViews();
69
70 for (String item : items) {
71 views.addView(createView(item));
72 }
73
74 refreshItemView(0);
75 }
76
77 private TextView createView(String item) {
78 TextView tv = new TextView(context);
79 tv.setLayoutParams(new LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
80 tv.setSingleLine(true);
81 tv.setTextSize(TypedValue.COMPLEX_UNIT_SP, 20);
82 tv.setText(item);
83 tv.setGravity(Gravity.CENTER);
84 int padding = dip2px(15);
85 tv.setPadding(padding, padding, padding, padding);
86 if (0 == itemHeight) {
87 itemHeight = getViewMeasuredHeight(tv);
88 views.setLayoutParams(new LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, itemHeight * displayItemCount));
89 LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) this.getLayoutParams();
90 this.setLayoutParams(new LinearLayout.LayoutParams(lp.width, itemHeight * displayItemCount));
91 }
92 return tv;
93 }
94
95 ......省略号......
96
97 @Override //上下直线的自绘
98 public void setBackgroundDrawable(Drawable background) {
99
100 if (viewWidth == 0) {
101 viewWidth = ((Activity) context).getWindowManager().getDefaultDisplay().getWidth();
102 }
103
104 if (null == paint) {
105 paint = new Paint();
106 paint.setColor(Color.parseColor("#83cde6"));
107 paint.setStrokeWidth(dip2px(1f));
108 }
109
110 background = new Drawable() {
111 @Override
112 public void draw(Canvas canvas) {
113 canvas.drawLine(viewWidth * 1 / 6, obtainSelectedAreaBorder()[0], viewWidth * 5 / 6,
114
115 obtainSelectedAreaBorder()[0], paint);
116
117 canvas.drawLine(viewWidth * 1 / 6, obtainSelectedAreaBorder()[1], viewWidth * 5 / 6,
118
119 obtainSelectedAreaBorder()[1], paint);
120
121 }
122 };
123
124 super.setBackgroundDrawable(background);
125 }
126
127 }
2、动态加载布局,并利用PopupWindow弹窗显示。
关键代码:
1 private void addView(int num){
2
3 ......省略号......
4
5 wheel_layout_view = LayoutInflater.from(this).inflate(R.layout.wheel_view, null);
6
7 ......省略号......
8
9 }
布局文件 wheel_view 效果图
1 private void popupWindows(List<String> list){
2 if (wheel_layout_view != null){
3
4 mPopupWindow = null;
5 mPopupWindow = new PopupWindow(wheel_layout_view);
6 mPopupWindow.setWidth(ViewGroup.LayoutParams.MATCH_PARENT);
7 mPopupWindow.setHeight(ViewGroup.LayoutParams.WRAP_CONTENT);
8
9 //点击外部,自动消失
10 mPopupWindow.setFocusable(true);
11 mPopupWindow.setOutsideTouchable(true);
12
13 ......省略号......
14
15 mPopupWindow.showAtLocation(ll_weidu_condition, Gravity.BOTTOM, 0, 0);
16 }
17 }
C、TabButton的实现
效果:
1、利用.9.png图标实现(简单、美观)
属性定义attrs.xml:
1 <?xml version="1.0" encoding="utf-8"?>
2 <resources>
3 <!-- 自定义的button控件,用于日期的选择-->
4 <declare-styleable name="TabButton">
5 <attr name="normal_bg_res" format="reference" />
6 <attr name="selected_bg_res" format="reference" />
7 </declare-styleable>
8 </resources>
布局文件:
1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
2 xmlns:custom="http://schemas.android.com/apk/res-auto" //声明自定义属性空间
3
4 ......省略号......
5
6 android:orientation="vertical">
7
8 ......省略号......
9
10 <xxxxxxxxxxx.customui.TabButton
11 style="@style/commonButton"
12 android:layout_width="0dp"
13 android:layout_margin="0dp"
14 android:layout_weight="1"
15 android:layout_height="40dp"
16 android:text="昨天"
17 android:textSize="22sp"
18 android:gravity="center"
19 android:background="@drawable/btn_left"
20 android:textColor="@color/blue"
21 custom:normal_bg_res="@drawable/btn_left"
22 custom:selected_bg_res="@drawable/btn_left_selected"
23 android:id="@+id/bt_yesterday" />
24
25 ......省略号......
26
27 </LinearLayout>
关键代码:
1 public class TabButton extends Button {
2 private int normal_bg_res;
3 private int selected_bg_res;
4
5 public TabButton(Context context) {
6 super(context);
7 }
8
9 public TabButton(Context context, AttributeSet attrs) {
10 super(context, attrs);
11
12 TypedArray typeArray = context.obtainStyledAttributes(attrs, R.styleable.TabButton);
13 normal_bg_res = typeArray.getResourceId(R.styleable.TabButton_normal_bg_res, 0);
14 selected_bg_res = typeArray.getResourceId(R.styleable.TabButton_selected_bg_res, 0);
15
16 typeArray.recycle();
17 }
18
19 public void setSelected(boolean selected) {
20 if (selected) {
21 setBackgroundResource(selected_bg_res);
22 setTextColor(Color.WHITE);
23 } else {
24 setBackgroundResource(normal_bg_res);
25 setTextColor(getResources().getColor(R.color.blue));
26 }
27 }
28 }
2、利用布局文件实现(复杂、灵活)。
更多样式,可以参数官方的SDK(android-sdk-windows\platforms\android-1.5\data\res\)
布局样式button_style:
1 <?xml version="1.0" encoding="utf-8"?>
2 <selector xmlns:android="http://schemas.android.com/apk/res/android">
3 <item android:state_pressed="true">
4 <shape android:shape="rectangle">
5 <solid android:color="#0d76e1" />
6 </shape>
7 </item>
8
9 <item android:state_focused="true">
10 <shape android:shape="rectangle">
11 <solid android:color="@color/Grey" />
12 </shape>
13 </item>
14
15 <item>
16 <shape android:shape="rectangle">
17 <solid android:color="@color/Grey" />
18 </shape>
19 </item>
20 </selector>
样式应用:
1 <Button android:id="@+id/tab_button"
2 android:layout_width="wrap_content"
3 android:layout_height="wrap_content"
4 android:background="@drawable/button_style">
3. 蒙板效果的实现
1、不保留标题栏蒙板的实现
效果:
原理:
1、弹窗时,设置背景窗体的透明度
2、取消弹窗时,恢复背景窗体的透明度
关键代码:
1 private void popupWindows(List<String> list){
2 //产生背景变暗效果
3 WindowManager.LayoutParams lp=getWindow().getAttributes();
4 lp.alpha = 0.4f;
5 getWindow().setAttributes(lp);
6
7 ......省略号......
8
9 mPopupWindow.setOnDismissListener(new PopupWindow.OnDismissListener() {
10 @Override
11 public void onDismiss() {
12 WindowManager.LayoutParams lp = getWindow().getAttributes();
13 lp.alpha = 1f;
14 getWindow().setAttributes(lp);
15 }
16 });
17
18 ......省略号......
19
20 }
2、保留标题栏蒙板的实现
效果:
原理:
1、根据需求,设置蒙板布局大小。
2、弹窗时,显示蒙板布局
2、取消弹窗时,隐藏蒙板布局
关键代码:
1、蒙板布局实现:
1 <!-- popup蒙板 -->
2 <LinearLayout
3 android:id="@+id/ll_popup_hide"
4 android:layout_width="match_parent"
5 android:background="@color/hide_bg"
6 android:orientation="vertical"
7 android:layout_height="match_parent">
8 </LinearLayout>
9
10 <color name="hide_bg">#88323232</color>
2、代码处理
1 ll_popup_hide.setVisibility(View.VISIBLE); //显示蒙板
2 ll_popup_hide.setVisibility(View.INVISIBLE); //隐藏蒙板
4. Activity的回收与操作超时的处理
1、Activity的回收
针对多个activity退出的处理
关键代码:
1、新建活动管理类:
1 public class ActivityCollector {
2 private static List<Activity> activityList = new ArrayList<Activity>();
3 public static void addActivity(Activity activity){
4 activityList.add(activity);
5 }
6 public static void removeActivity(Activity activity){
7 activityList.remove(activity);
8 }
9
10 public static void finishAllButLast(){
11 Activity activity = activityList.get(activityList.size()-1);
12 removeActivity(activity);
13
14 for (Activity activityItem: activityList){
15 if (!activityItem.isFinishing()){
16 activityItem.finish();
17 }
18 }
19
20 activityList.clear();
21 activityList.add(activity);
22 }
23
24 public static void finishAll(){
25 for (Activity activity: activityList){
26 if (!activity.isFinishing()){
27 activity.finish();
28 }
29 }
30
31 activityList.clear();
32 }
33 }
2、创建基类BaseActivity,并使所有的activity继承自该基类 。在创建时,添加到活动管理器,销毁时,从活动管理器中移除。
1 public class BaseActivity extends Activity {
2 @Override
3 protected void onCreate(Bundle savedInstanceState) {
4 super.onCreate(savedInstanceState);
5 ActivityCollector.addActivity(this);
6 }
7
8 @Override
9 protected void onDestroy() {
10 super.onDestroy();
11 ActivityCollector.removeActivity(this);
12 }
13 }
如果需要销毁所有activity,只需调用finishAll()即可
2、操作超时处理
原理:
1、在activity的stop函数中,根据app进程IMPORTANCE_FOREGROUND判断app在前台或后台
2、在activity的onResume函数中,做超时检查。
关键代码:
1 abstract public class TimeOutCheckActivity extends BaseActivity {
2 private boolean isLeave = false;
3
4 @Override
5 protected void onCreate(Bundle savedInstanceState) {
6 super.onCreate(savedInstanceState);
7 pref = getSharedPreferences(Constant.CONFIG_NAME, Context.MODE_PRIVATE);
8 }
9
10 /**
11 * 回调函数,方便测试
12 * @return
13 */
14 abstract protected String getTag();
15
16 ......省略号......
17
18 /***
19 * 当用户使程序恢复为前台显示时执行onResume()方法,在其中判断是否超时.
20 */
21 @Override
22 protected void onResume() {
23 // Log.i("Back",getTag() + ",onResume,是否在前台:" + isOnForeground());
24 super.onResume();
25 if (isLeave) {
26 isLeave = false;
27 timeOutCheck();
28 }
29 }
30
31 @Override
32 protected void onStop() {
33 super.onStop();
34 if (!isOnForeground()){
35 if (!isLeave && isOpenALP()) {
36 isLeave = true;
37 saveStartTime();
38 }
39 }
40 }
41
42 public void timeOutCheck() {
43 long endtime = System.currentTimeMillis();
44 if (endtime - getStartTime() >= Constant.TIMEOUT_ALP * 1000) {
45 Util.toast(this, "超时了,请重新验证");
46 String alp = pref.getString(Constant.ALP, null);
47 if (alp == null || alp == "") {
48 } else {
49 Intent intent = new Intent(this, UnlockGesturePasswordActivity.class);
50 intent.putExtra("pattern", alp);
51 intent.putExtra("login",false); //手势验证,不进行登录验证
52 intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK);
53 // 打开新的Activity
54 startActivityForResult(intent, Constant.REQ_COMPARE_PATTERN_TIMEOUT_CHECK);
55 }
56 }
57 }
58
59 public void saveStartTime() {
60 pref.edit().putLong(Constant.START_TIME, System.currentTimeMillis()).commit();
61 }
62
63 public long getStartTime() {
64 long startTime = 0;
65 try {
66 startTime = pref.getLong(Constant.START_TIME, 0);
67 }catch (Exception e){
68 startTime = 0;
69 }
70 return startTime;
71 }
72
73 /**
74 * 程序是否在前端运行,通过枚举运行的app实现。防止重复超时检测多次,保证只有一个activity进入超时检测
75 *当用户按home键时,程序进入后端运行,此时会返回false,其他情况引起activity的stop函数的调用,会返回true
76 * @return
77 */
78 public boolean isOnForeground() {
79 ActivityManager activityManager = (ActivityManager) getApplicationContext().getSystemService(Context.ACTIVITY_SERVICE);
80 String packageName = getApplicationContext().getPackageName();
81
82 List<ActivityManager.RunningAppProcessInfo> appProcesses = activityManager.getRunningAppProcesses();
83 if (appProcesses == null)
84 return false;
85
86 for (ActivityManager.RunningAppProcessInfo appProcess : appProcesses) {
87 if (appProcess.processName.equals(packageName)
88 && appProcess.importance == ActivityManager.RunningAppProcessInfo.IMPORTANCE_FOREGROUND) {
89 return true;
90 }
91 }
92
93 return false;
94 }
95 }
补充说明:
可以根据importance的不同来判断前台或后台,RunningAppProcessInfo 里面的常量IMTANCE就是上面所说的前台后台,其实IMOPORTANCE是表示这个app进程的重要性,因为系统回收时候,会根据IMOPORTANCE来回收进程的。具体可以去看文档。
1 public static final int IMPORTANCE_BACKGROUND = 400//后台
2 public static final int IMPORTANCE_EMPTY = 500//空进程
3 public static final int IMPORTANCE_FOREGROUND = 100//在屏幕最前端、可获取到焦点
4 可理解为Activity生命周期的OnResume();
5 public static final int IMPORTANCE_SERVICE = 300//在服务中
6 public static final int IMPORTANCE_VISIBLE =
7 200//在屏幕前端、获取不到焦点可理解为Activity生命周期的OnStart();