将fragment与layout结合使用,一般都是主activity以frame填充activity的方式交互管理fragment :
1.由于用到getsupportfragmentmanager()之类,所以主activity的extends需为fragmentactivity:
1
2
3
|
public class mainactivity extends fragmentactivity{ .......... } |
2.主activity的layout(xml文件)中建立多个frame并定义其android:id="@+id/xxx"
3.主activity内操作函数中,由查找id来对这些framelayout进行activity填充:
添加语句如下
getsupportfragmentmanager().begintransaction().add(r.id.fragment_container2,new nullfrag()).commit();
取得支持fragment管理()->开始交易()->添加(frame的id , fragment).交付();
替换语句如下
getsupportfragmentmanager().begintransaction().replace(r.id.fragment_container2,new nullfrag()).commit();
取得支持fragment管理()->开始交易()->替代(frame的id , fragment).交付();
例:
public void click_btn_flag02(view view){
getsupportfragmentmanager().begintransaction().replace(r.id.fragment_container2,new midfrag()).commit();
}
注:函数参数要用view
下面我们来看实例:
效果图的左边是一个列表,右边是列表item的详情。
先看一下布局文件(layout):
1
2
3
4
5
6
7
8
9
10
11
12
|
<?xml version= "1.0" encoding= "utf-8" ?> <linearlayout xmlns:android= "http://schemas.android.com/apk/res/android" android:orientation= "horizontal" android:layout_width= "match_parent" android:layout_height= "match_parent" > <fragment class = "com.fragment.main.titlesfragment" android:id= "@+id/titles" android:layout_weight= "1" android:layout_width= "0px" android:layout_height= "match_parent" /> <framelayout android:id= "@+id/details" android:layout_weight= "1" android:layout_width= "0px" android:layout_height= "match_parent" android:background= "?android:attr/detailselementbackground" /> </linearlayout> |
布局文件中使用了fragment标签和framelayout标签。android fragment使用 中介绍了2中嵌入fragment的方法,这个实例中都用到,从布局文件看到有了fragment标签,这是一种使用方法,framelayout标签将会成为第二种加载fragment的载体view。
看一下程序实现(com.fragment.main.titlesfragment):
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
|
public class titlesfragment extends listfragment { int mcurcheckposition = 0 ; int mshowncheckposition = - 1 ; @override public void onactivitycreated(bundle savedinstancestate) { super .onactivitycreated(savedinstancestate); setlistadapter( new arrayadapter<string>(getactivity(), android.r.layout.simple_list_item_activated_1, shakespeare.titles)); //使用静态数组填充列表 if (savedinstancestate != null ) { mcurcheckposition = savedinstancestate.getint( "curchoice" , 0 ); mshowncheckposition = savedinstancestate.getint( "shownchoice" , - 1 ); } getlistview().setchoicemode(listview.choice_mode_single); showdetails(mcurcheckposition); } @override public void onsaveinstancestate(bundle outstate) { super .onsaveinstancestate(outstate); outstate.putint( "curchoice" , mcurcheckposition); outstate.putint( "shownchoice" , mshowncheckposition); } @override public void onlistitemclick(listview l, view v, int position, long id) { showdetails(position); } /** *显示listview item 详情 */ void showdetails( int index) { mcurcheckposition = index; getlistview().setitemchecked(index, true ); if (mshowncheckposition != mcurcheckposition) { detailsfragment df = detailsfragment.newinstance(index); fragmenttransaction ft = getfragmentmanager() .begintransaction(); ft.replace(r.id.details, df); ft.settransition(fragmenttransaction.transit_fragment_fade); ft.commit(); mshowncheckposition = index; } } } |
titlesfragment
titlesfragment继承自fragment的子类listfragment,使用了一个静态数组填充列表,重写了onlistitemclick方法,showdetails方法展示listview item的详情。
1
2
3
4
5
|
detailsfragment df = detailsfragment.newinstance(index); //获取详情fragment的实例 fragmenttransaction ft = getfragmentmanager().begintransaction(); //获取fragmenttransaction 实例 ft.replace(r.id.details, df); //使用detailsfragment 的实例 ft.settransition(fragmenttransaction.transit_fragment_fade); ft.commit(); //提交 |
看一下detailsfragment :
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
|
public class detailsfragment extends fragment { /** * create a new instance of detailsfragment, initialized to * show the text at 'index'. */ public static detailsfragment newinstance( int index) { detailsfragment f = new detailsfragment(); // supply index input as an argument. bundle args = new bundle(); args.putint( "index" , index); f.setarguments(args); return f; } @override public view oncreateview(layoutinflater inflater, viewgroup container, bundle savedinstancestate) { if (container == null ) { return null ; } scrollview scroller = new scrollview(getactivity()); textview text = new textview(getactivity()); int padding = ( int ) typedvalue.applydimension( typedvalue.complex_unit_dip, 4 , getactivity().getresources() .getdisplaymetrics()); text.setpadding(padding, padding, padding, padding); scroller.addview(text); text.settext(shakespeare.dialogue[getarguments().getint( "index" , 0 )]); return scroller; } } |
detailsfragment 中使用newinstance(int index)方法产生detailsfragment 实例并接受整型参数,重载了oncreateview方法创建view。