访客 Fragment是什么
具备生命周期；依托Activity运行
Fragment运行
<?xmlversion="1.0"encoding="utf-8"?><LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"tools:context=".Fragemnt1"><!--TODO:Updateblankfragmentlayout--><TextViewandroid:id="@id/tv1"android:layout_width="200dp"android:layout_height="200dp"android:text="@string/hello_blank_fragment"/><Buttonandroid:layout_width="200dp"android:layout_height="200dp"android:text="按钮1"android:id="@id/btn1"/></LinearLayout><?xmlversion="1.0"encoding="utf-8"?><LinearLayoutandroid:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"xmlns:android="http://schemas.android.com/apk/res/android"><fragmentandroid:id="@id/fragment1"android:name="com.example.fragmentlearn1.Fragemnt1"android:layout_width="match_parent"android:layout_height="match_parent"/><fragmentandroid:id="@id/fragment2"android:name="com.example.fragmentlearn1.Fragemnt2"android:layout_weight="1"android:layout_width="match_parent"android:layout_height="match_parent"/></LinearLayout>packagecom.example.fragmentlearn1;importandroid.os.Bundle;importandroidx.fragment.app.Fragment;importandroid.view.LayoutInflater;importandroid.view.View;importandroid.view.ViewGroup;importandroid.widget.Button;importandroid.widget.TextView;importorg.w3c.dom.Text;/***Asimple{@linkFragment}subclass.*Usethe{@linkFragemnt1#newInstance}factorymethodto*createaninstanceofthisfragment.*/publicclassFragemnt1extendsFragment{//TODO:Renameparameterarguments,choosenamesthatmatch//thefragmentinitializationparameters,e.g.ARG_ITEM_NUMBERprivatestaticfinalStringARG_PARAM1="param1";privatestaticfinalStringARG_PARAM2="param2";//TODO:RenameandchangetypesofparametersprivateStringmParam1;privateStringmParam2;publicFragemnt1(){//Requiredemptypublicconstructor}privateViewroot;privateTextViewtextView;privateButtonbutton;/***Usethisfactorymethodtocreateanewinstanceof*thisfragmentusingtheprovidedparameters.**@paramparam1Parameter1.*@paramparam2Parameter2.*@returnAnewinstanceoffragmentFragemnt1.*///TODO:RenameandchangetypesandnumberofparameterspublicstaticFragemnt1newInstance(Stringparam1,Stringparam2){Fragemnt1fragment=newFragemnt1();Bundleargs=newBundle();args.putString(ARG_PARAM1,param1);args.putString(ARG_PARAM2,param2);fragment.setArguments(args);returnfragment;}@OverridepublicvoidonCreate(BundlesavedInstanceState){super.onCreate(savedInstanceState);if(getArguments()!=null){mParam1=getArguments().getString(ARG_PARAM1);mParam2=getArguments().getString(ARG_PARAM2);}}@OverridepublicViewonCreateView(LayoutInflaterinflater,ViewGroupcontainer,BundlesavedInstanceState){if(root==null)//Inflatethelayoutforthisfragmentroot=inflater.inflate(R.layout.fragment_fragemnt1,container,false);textView=root.findViewById(R.id.tv1);button=root.findViewById(R.id.btn1);button.setOnClickListener(newView.OnClickListener(){@OverridepublicvoidonClick(Viewv){textView.setText("啦啦啦啦啦");}});returnroot;}}packagecom.example.fragmentlearn1;importandroidx.appcompat.app.AppCompatActivity;importandroid.os.Bundle;publicclassMainActivityextendsAppCompatActivity{@OverrideprotectedvoidonCreate(BundlesavedInstanceState){super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);}}