Navigation3
作者：互联网
两个页面可以通过连接ViewModel来共享数据。
这里也用了databinding
MasterFragment
package com.example.navviewmodel;
import android.os.Bundle;
import androidx.databinding.DataBindingUtil;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentManager;
import androidx.lifecycle.SavedStateViewModelFactory;
import androidx.lifecycle.ViewModelProvider;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.SeekBar;
import com.example.navviewmodel.databinding.FragmentMasterBinding;
/**
* A simple {@link Fragment} subclass.
*/
public class MasterFragment extends Fragment {
public MasterFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, final ViewGroup container,
Bundle savedInstanceState) {
final MyViewModel myViewModel;
myViewModel=new ViewModelProvider(getActivity()).get(MyViewModel.class);
FragmentMasterBinding binding;
binding= DataBindingUtil.inflate(inflater,R.layout.fragment_master,container,false);
binding.setData(myViewModel);
binding.setLifecycleOwner(getActivity());
binding.button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
NavController controller= Navigation.findNavController(view);
controller.navigate(R.id.action_masterFragment_to_detailFragment);
}
});
binding.seekBar.setProgress(myViewModel.getNumber().getValue());
binding.seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int i, boolean b) {
myViewModel.getNumber().setValue(i);
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
// Inflate the layout for this fragment
//return inflater.inflate(R.layout.fragment_master, container, false);
return binding.getRoot();
}
}
DetailFragment
package com.example.navviewmodel;
import android.content.Context;
import android.net.Uri;
import android.os.Bundle;
import androidx.databinding.DataBindingUtil;
import androidx.fragment.app.Fragment;
import androidx.lifecycle.SavedStateViewModelFactory;
import androidx.lifecycle.ViewModelProvider;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import com.example.navviewmodel.databinding.FragmentDetailBinding;
/**
* A simple {@link Fragment} subclass.
*/
public class DetailFragment extends Fragment {
public DetailFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, final ViewGroup container,
Bundle savedInstanceState) {
MyViewModel myViewModel;
myViewModel=new ViewModelProvider(getActivity()).get(MyViewModel.class);
FragmentDetailBinding binding;
binding= DataBindingUtil.inflate(inflater,R.layout.fragment_detail,container,false);
binding.setData(myViewModel);
binding.setLifecycleOwner(getActivity());
binding.button4.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
NavController controller= Navigation.findNavController(view);
controller.navigate(R.id.action_detailFragment_to_masterFragment);
}
});
return binding.getRoot();
// Inflate the layout for this fragment
//return inflater.inflate(R.layout.fragment_detail, container, false);
}
}
MyViewModel
package com.example.navviewmodel;
import androidx.lifecycle.MutableLiveData;
import androidx.lifecycle.ViewModel;
public class MyViewModel extends ViewModel {
private MutableLiveData<Integer> number;
public MutableLiveData<Integer> getNumber(){
if(number==null){
number=new MutableLiveData<>();
number.setValue(0);
}
return number;
}
public void add(int x){
number.setValue(number.getValue()+x);
if(number.getValue()<0){
number.setValue(0);
}
}
}
Master.xml
<?xml version="1.0" encoding="utf-8"?>
<layout 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">
<data>
<variable
name="data"
type="com.example.navviewmodel.MyViewModel" />
</data>
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MasterFragment">
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@{String.valueOf(data.number)}"
android:textSize="30sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.181" />
<SeekBar
android:id="@+id/seekBar"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:max="10"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.366" />
<Button
android:id="@+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="进入"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>
Detail.xml
<?xml version="1.0" encoding="utf-8"?>
<layout 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">
<data>
<variable
name="data"
type="com.example.navviewmodel.MyViewModel" />
</data>
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".DetailFragment">
<TextView
android:id="@+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@{String.valueOf(data.number)}"
android:textSize="30sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.538"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.172" />
<Button
android:id="@+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="76dp"
android:text="-"
android:onClick="@{()->data.add(-1)}"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="@+id/button3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="+"
android:onClick="@{()->data.add(1)}"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toEndOf="@+id/button2"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="@+id/button4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="返回"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.507"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.711" />
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>
标签：layout,androidx,binding,import,Navigation3,public,android 来源： https://www.cnblogs.com/nian-nian/p/15779988.html