kotlin for android 之fragment
如果只要求手机屏幕上一部分改变，用新建activity的方法就不行了，这时就要使用fragment。新建一个项目然后再MainActivity.kt文件旁新建2个fragment，方法是，鼠标右键点目录->new->Fragment->Fragment(Blank)，系统会自动生成xml文件跟kt文件，修改BlankFragment.kt文件：package com.example.xinwei.fragmentkotlin
import android.app.Fragment
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
class BlankFragment : Fragment() {
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?): View? {
return inflater.inflate(R.layout.fragment_blank, container, false)
}
}
修改BlankFragment2.kt文件：
package com.example.xinwei.fragmentkotlin
import android.app.Fragment
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
class BlankFragment2 : Fragment() {
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?): View? {
return inflater.inflate(R.layout.fragment_blank_fragment2, container, false)
}
}
修改fragment_blank.xml
<FrameLayout xmlns: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"
tools:context="com.example.xinwei.fragmentkotlin.BlankFragment">
<!-- TODO: Update blank fragment layout -->
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#ffff00"
android:text="@string/hello_blank_fragment" />
</FrameLayout>
修改fragment_blank_fragment2.xml
<FrameLayout xmlns: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"
tools:context="com.example.xinwei.fragmentkotlin.BlankFragment2">
<!-- TODO: Update blank fragment layout -->
<TextView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#ff0000"
android:text="@string/hello_blank_fragment" />
</FrameLayout>
修改activity_main.xml文件
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<LinearLayout
android:id="@+id/idlayout1"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="8"
android:orientation="vertical"/>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:orientation="horizontal">
<Button
android:id="@+id/idbutton1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="button1" />
<Button
android:id="@+id/idbutton2"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="button2" />
</LinearLayout>
</LinearLayout>
修改MainActivity.kt
package com.example.xinwei.fragmentkotlin
import android.app.FragmentTransaction
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.view.View
import kotlinx.android.synthetic.main.activity_main.*
class MainActivity : AppCompatActivity(),View.OnClickListener {
override fun onClick(p0: View?) {
when(p0?.id){
idbutton1.id->{
var manager=fragmentManager
var transaction=manager.beginTransaction()
transaction?.replace(R.id.idlayout1,BlankFragment())
transaction?.commit()
}
idbutton2.id->{
var manager=fragmentManager
var transaction=manager.beginTransaction()
transaction?.replace(R.id.idlayout1,BlankFragment2())
transaction?.commit()
}
}
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
idbutton1.setOnClickListener(this)
idbutton2.setOnClickListener(this)
var manager=fragmentManager
var transaction=manager.beginTransaction()
transaction?.replace(R.id.idlayout1,BlankFragment())
transaction?.commit()
}
}
效果图为：
页:
[1]