我想更改 android 中 Child Activity 选项卡的标题

i want to change the title of the Tabbed Child Activity in android

<android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:layout_weight="1"
        app:layout_scrollFlags="scroll|enterAlways"
        app:popupTheme="@style/AppTheme.PopupOverlay"
        app:title="@string/app_name">

    </android.support.v7.widget.Toolbar>

以上是actitvity_main2.xml中的代码,即activity_main.xml的childactivity。

我想在从 Main activity 转到 Main2Acitivty 时更改此 child activity 的标题。这是带有主要应用程序(即股票)标题的图片。

我想在加载 Main2Activity(此 activity 包含选项卡式视图,如图所示)时将标题更改为其他内容。我尝试使用 getActionBar().setTitle(<name to put on title>); 并且还使用了 setTitle(<name to put in the title>) 但没有任何效果。

请帮忙,因为我是 android 的新手。

我正在提供所有代码。

MainActivity.java

import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    private ViewPager mViewPager;
    private SectionsPagerAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);


        // Set up the ViewPager with the sections adapter.
        mViewPager = (ViewPager) findViewById(R.id.container);
        setupViewPager(mViewPager);

        TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
        tabLayout.setupWithViewPager(mViewPager);         

// This listener helps for changing name on title when you change page through slide or click on tab
        mViewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
                if(adapter != null){
                    getSupportActionBar().setTitle(adapter.getPageTitle(position));
                }
            }

            @Override
            public void onPageSelected(int position) {

            }

            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });
    }    

    private void setupViewPager(ViewPager viewPager) {
        adapter = new SectionsPagerAdapter(getSupportFragmentManager());
        adapter.addFragment(new TabOne(), "ONE");
        adapter.addFragment(new TabSecond(), "TWO");
        adapter.addFragment(new TabThird(), "THREE");
        viewPager.setAdapter(adapter);
    }


    public class SectionsPagerAdapter extends FragmentPagerAdapter {
        private final List<Fragment> mFragmentList = new ArrayList<>();
        private final List<String> mFragmentTitleList = new ArrayList<>();

        public SectionsPagerAdapter(FragmentManager fm) {
            super(fm);
        }

        public void addFragment(Fragment fragment, String title) {
            mFragmentList.add(fragment);
            mFragmentTitleList.add(title);
        }

        @Override
        public Fragment getItem(int position) {
            return mFragmentList.get(position);
        }

        @Override
        public int getCount() {
            return mFragmentList.size();
        }

        @Override
        public CharSequence getPageTitle(int position) {
            return mFragmentTitleList.get(position);
        }
    }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
    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="com.taxsmart.testapplication.MainActivity">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/AppTheme.PopupOverlay"/>

        <android.support.design.widget.TabLayout
            android:id="@+id/tabs"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />

    </android.support.design.widget.AppBarLayout>

    <android.support.v4.view.ViewPager
        android:id="@+id/container"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior" />

</android.support.design.widget.CoordinatorLayout>

在 gradle 文件中添加依赖项

compile 'com.android.support:appcompat-v7:26.1.0'
compile 'com.android.support.constraint:constraint-layout:1.0.2'
compile 'com.android.support:design:26.1.0'

有3个tab是fragment。所有片段的 xml 文件

tabone.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:layout_gravity="center">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="TabOne"
        android:gravity="center"/>

</LinearLayout>

tabsecond.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:layout_gravity="center">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="TabSecond"
        android:gravity="center"/>

</LinearLayout>

tabthird.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="match_parent"
              android:layout_height="wrap_content"
              android:layout_gravity="center">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="TabThird"
        android:gravity="center"/>

</LinearLayout>

全部片段java文件 TabOne.java

import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class TabOne extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.tabone, container, false);
        return rootView;
    }
}

TabSecond.java

import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;


public class TabSecond extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.tabsecond, container, false);
        return rootView;
    }
}

TabThird.java

import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class TabThird extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.tabthird, container, false);
        return rootView;
    }
}

希望这能解决您的问题。

在 sytle.xml 文件中制作样式

<style name="AppTheme.NoActionBar">
    <item name="windowActionBar">false</item>
    <item name="windowNoTitle">true</item>
</style>

从您的第一个 activity

调用以下代码
Intent intent = new Intent(FirstActivity.this, MainActivity.class);
intent.putExtra("TitleBarName","FirstActivity");
startActivity(intent);

在 SecondActivity 上

    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    String titleName = getIntent().getStringExtra("TitleBarName");
    getSupportActionBar().setTitle(titleName);

并确保签入清单文件。

如果您使用工具栏,则必须将此主题放在清单文件activity中

    <activity
        android:name=".MainActivity"
        android:label="@string/app_name"
        android:theme="@style/AppTheme.NoActionBar">
    </activity>

希望这能解决您的问题。