java - TabLayout OnPageChangeListener 不能应用于“()”

Question

我在构建项目时在我的项目中遇到此错误，请任何人帮助

这是代码：-

'TabLayoutOnPageChangeListener(com.google.android.material.tabs.TabLayout)' in 'com.google.android.material.tabs.TabLayout.TabLayoutOnPageChangeListener' cannot be applied to '()'

这是我的java类

package com.heven.meme2;

import android.os.Bundle;

import androidx.appcompat.app.AppCompatActivity;
import androidx.viewpager.widget.ViewPager;

import com.google.android.material.tabs.TabLayout;
import com.heven.meme2.adapter.ViewPagerAdapter;

//import android.widget.TabLayout;


public class MainActivity extends AppCompatActivity {

    private TabLayout tabLayout;
    private ViewPager viewPager;
    ViewPagerAdapter pagerAdapter;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        init();

        addTabs();

    }

    private void init() {


        viewPager = findViewById(R.id.viewPager);
        tabLayout = findViewById(R.id.tabLaout);

    }

    private void addTabs(){

        tabLayout.addTab(tabLayout.newTab().setIcon(R.drawable.ic_home));
        tabLayout.addTab(tabLayout.newTab().setIcon(R.drawable.ic_search));
        tabLayout.addTab(tabLayout.newTab().setIcon(R.drawable.ic_add));
        tabLayout.addTab(tabLayout.newTab().setIcon(R.drawable.ic_heart));
        tabLayout.addTab(tabLayout.newTab().setIcon(R.drawable.ic_home_fill));

        tabLayout.setTabGravity(TabLayout.GRAVITY_CENTER);
        tabLayout.setTabMode(TabLayout.MODE_SCROLLABLE);

        pagerAdapter = new ViewPagerAdapter(getSupportFragmentManager(), tabLayout.getTabCount());
        viewPager.setAdapter(pagerAdapter);

        ViewPager.OnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener());

        tabLayout.getTabAt(0).setIcon(R.drawable.ic_home_fill);

        tabLayout.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
            @Override
            public void onTabSelected(TabLayout.Tab tab) {

                viewPager.setCurrentItem(tab.getPosition());

                switch (tab.getPosition()){

                    case 0:
                        tabLayout.getTabAt(0).setIcon(R.drawable.ic_home_fill);
                        break;
                    case 1:
                        tabLayout.getTabAt(1).setIcon(R.drawable.ic_search);
                        break;
                    case 2:
                        tabLayout.getTabAt(2).setIcon(R.drawable.ic_add);
                        break;
                    case 3:
                        tabLayout.getTabAt(3).setIcon(R.drawable.ic_heart_fill);
                        break;
                    case 4:
                        tabLayout.getTabAt(4).setIcon(android.R.drawable.ic_media_play);
                        break;
                }

            }

            @Override
            public void onTabUnselected(TabLayout.Tab tab) {

                switch (tab.getPosition()){

                    case 0:
                        tabLayout.getTabAt(0).setIcon(R.drawable.ic_home);
                        break;
                    case 1:
                        tabLayout.getTabAt(1).setIcon(R.drawable.ic_search);
                        break;
                    case 2:
                        tabLayout.getTabAt(2).setIcon(R.drawable.ic_add);
                        break;
                    case 3:
                        tabLayout.getTabAt(3).setIcon(R.drawable.ic_heart);
                        break;
                    case 4:
                        tabLayout.getTabAt(4).setIcon(android.R.drawable.ic_media_pause);
                        break;
                }

            }

            @Override
            public void onTabReselected(TabLayout.Tab tab) {

                switch (tab.getPosition()){

                    case 0:
                        tabLayout.getTabAt(0).setIcon(R.drawable.ic_home_fill);
                        break;
                    case 1:
                        tabLayout.getTabAt(1).setIcon(R.drawable.ic_search);
                        break;
                    case 2:
                        tabLayout.getTabAt(2).setIcon(R.drawable.ic_add);
                        break;
                    case 3:
                        tabLayout.getTabAt(3).setIcon(R.drawable.ic_heart_fill);
                        break;
                    case 4:
                        tabLayout.getTabAt(4).setIcon(android.R.drawable.ic_media_play);
                        break;
                }

            }
        });

    }

}

这是我的 xml 文件

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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"
    tools:context=".MainActivity">

    <androidx.viewpager.widget.ViewPager
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_above="@id/tabLaout"
        android:id="@+id/viewPager"/>

    <com.google.android.material.tabs.TabLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/tabLaout"
        android:layout_alignParentBottom="true"/>
</RelativeLayout>

实际上，我正在关注 youtube 上的教程，它对他有用，但对我无效。

我也通过引用上一个问题添加了 android.material:material:1.4.0" 但它对我没有用。

标签： javaandroid

Answer 1

由于文档TabLayoutOnPageChangeListener中没有空的构造函数

替换这一行：

ViewPager.OnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener());

有了这个：

viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));