我正在尝试使用viewpager和fragments创建一个多页表单。表单需要有底部的点和点左右两侧的“后退”/“下一步”按钮,下一步按钮在最后一张幻灯片上变为“完成”。
我设法使底部的圆点和按钮起作用。然而,我迷失在如何使返回按钮不可见时,在第一个片段和下一个按钮在最后。
我的代码:
主活动.java
import androidx.appcompat.app.AppCompatActivity;
import androidx.viewpager.widget.ViewPager;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import com.google.android.material.tabs.TabLayout;
public class MainActivity extends AppCompatActivity {
TabLayout tabLayout;
ViewPager viewPager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tabLayout = findViewById(R.id.tabLayout);
viewPager = findViewById(R.id.viewPager);
getTabs();
}
public void getTabs(){
final ViewPagerAdapter viewPagerAdapter = new ViewPagerAdapter(getSupportFragmentManager());
new Handler().post(new Runnable() {
@Override
public void run() {
viewPagerAdapter.addFragment(oneFragment.getInstance(),null);
viewPagerAdapter.addFragment(twoFragment.getInstance(),null);
viewPagerAdapter.addFragment(threeFragment.getInstance(),null);
viewPager.setAdapter(viewPagerAdapter);
tabLayout.setupWithViewPager(viewPager);
}
});
}
//Implement the listeners for the back and previous items
public void goBack(View view) {
viewPager.setCurrentItem(viewPager.getCurrentItem()-1);
}
public void goNext(View view) {
viewPager.setCurrentItem(viewPager.getCurrentItem()+1);
}
}
活动\u main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical"
tools:context=".MainActivity">
<androidx.viewpager.widget.ViewPager
android:id="@+id/viewPager"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true">
<Button
android:id="@+id/back"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/back"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:onClick="goBack"/>
<Button
android:id="@+id/next"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/next"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:onClick="goNext"/>
<com.google.android.material.tabs.TabLayout
android:id="@+id/tabLayout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:tabBackground="@drawable/tab_selector"
app:tabIndicatorHeight="0dp" />
</androidx.constraintlayout.widget.ConstraintLayout>
</RelativeLayout>
viewpageradapter.java文件
import java.util.ArrayList;
import java.util.List;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentStatePagerAdapter;
public class ViewPagerAdapter extends FragmentStatePagerAdapter {
private List<Fragment> fragmentList = new ArrayList<>();
private List<String> stringList = new ArrayList<>();
public ViewPagerAdapter(@NonNull FragmentManager fm) {
super(fm);
}
@NonNull
@Override
public Fragment getItem(int position) {
return fragmentList.get(position);
}
@Override
public int getCount() {
return fragmentList.size();
}
@Nullable
@Override
public CharSequence getPageTitle(int position) {
return stringList.get(position);
}
public void addFragment(Fragment fragment, String title){
fragmentList.add(fragment);
stringList.add(title);
}
}
片段示例:布局行为1的onefragment.java
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;
public class OneFragment extends Fragment {
public static OneFragment getInstance(){
OneFragment oneFragment = new OneFragment();
return oneFragment;
}
@Override
public void onAttach(@NonNull Context context) {
super.onAttach(context);
}
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.row_one, container,false);
return view;
}
}
1条答案
按热度按时间uttx8gqw1#
您可以添加
addOnPageChangeListener
Listener到viewpager,然后在onPageSelected()
回调比较所选/当前position
到第一个(位置=0)或最后一个位置。