Fatal编程技术网
  • java/
  • 使用Java导入强制类

使用Java导入强制类

java android-studio

使用Java导入强制类,java,android-studio,Java,Android Studio,在构建我的应用程序时，我注意到当我在MainActivity（.Java）中导入任何Java util时，我的应用程序强制关闭 原来是这个, package com.ivancristina.navigazione; import android.content.Context; import android.os.Bundle; import android.support.design.widget.FloatingActionButton; import android.support.

在构建我的应用程序时，我注意到当我在MainActivity（.Java）中导入任何Java util时，我的应用程序强制关闭

原来是这个,

package com.ivancristina.navigazione;

import android.content.Context;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.NavigationView;
import android.support.design.widget.Snackbar;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.LinearLayout;


public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener {

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        getSupportActionBar().setTitle("");

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.setDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);
    }

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }



    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        if (id == R.id.nav_formule) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_formule, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        } else if (id == R.id.nav_esempi) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_esempi, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        } else if (id == R.id.nav_home) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_main, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }
}

package com.ivancristina.navigazione;

import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.NavigationView;
import android.support.design.widget.Snackbar;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.SparseBooleanArray;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.Toast;

import java.util.*;


public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener {

        private ImageView logo;
        private Button github;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        initialize();
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        getSupportActionBar().setTitle("");

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.setDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);
    }

    private void  initialize() {
        logo = (ImageView) findViewById(R.id.logo);
        github = (Button) findViewById(R.id.github);


        logo.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View _v) {
                showMessage("OnClick");
            }
        });
        github.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View _v) {
                startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("http://www.github.com/ivancristina")));
            }
        });

    }

    // created automatically
    private void showMessage(String _s) {
        Toast.makeText(getApplicationContext(), _s, Toast.LENGTH_SHORT).show();
    }

    private int getRandom(int _minValue ,int _maxValue){
        Random random = new Random();
        return random.nextInt(_maxValue - _minValue + 1) + _minValue;
    }

    public ArrayList<Double> getCheckedItemPositionsToArray(ListView _list) {
        ArrayList<Double> _result = new ArrayList<Double>();
        SparseBooleanArray _arr = _list.getCheckedItemPositions();
        for (int _iIdx = 0; _iIdx < _arr.size(); _iIdx++) {
            if (_arr.valueAt(_iIdx))
                _result.add((double)_arr.keyAt(_iIdx));
        }
        return _result;
    }

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }



    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        if (id == R.id.nav_formule) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_formule, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        } else if (id == R.id.nav_esempi) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_esempi, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        } else if (id == R.id.nav_home) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_main, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }
}
而使用java的是这个：

package com.ivancristina.navigazione;

import android.content.Context;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.NavigationView;
import android.support.design.widget.Snackbar;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.LinearLayout;


public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener {

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        getSupportActionBar().setTitle("");

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.setDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);
    }

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }



    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        if (id == R.id.nav_formule) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_formule, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        } else if (id == R.id.nav_esempi) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_esempi, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        } else if (id == R.id.nav_home) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_main, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }
}

package com.ivancristina.navigazione;

import android.content.Context;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.NavigationView;
import android.support.design.widget.Snackbar;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.SparseBooleanArray;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.Toast;

import java.util.*;


public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener {

        private ImageView logo;
        private Button github;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        initialize();
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        getSupportActionBar().setTitle("");

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.setDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);
    }

    private void  initialize() {
        logo = (ImageView) findViewById(R.id.logo);
        github = (Button) findViewById(R.id.github);


        logo.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View _v) {
                showMessage("OnClick");
            }
        });
        github.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View _v) {
                startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("http://www.github.com/ivancristina")));
            }
        });

    }

    // created automatically
    private void showMessage(String _s) {
        Toast.makeText(getApplicationContext(), _s, Toast.LENGTH_SHORT).show();
    }

    private int getRandom(int _minValue ,int _maxValue){
        Random random = new Random();
        return random.nextInt(_maxValue - _minValue + 1) + _minValue;
    }

    public ArrayList<Double> getCheckedItemPositionsToArray(ListView _list) {
        ArrayList<Double> _result = new ArrayList<Double>();
        SparseBooleanArray _arr = _list.getCheckedItemPositions();
        for (int _iIdx = 0; _iIdx < _arr.size(); _iIdx++) {
            if (_arr.valueAt(_iIdx))
                _result.add((double)_arr.keyAt(_iIdx));
        }
        return _result;
    }

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }



    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();

        if (id == R.id.nav_formule) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_formule, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        } else if (id == R.id.nav_esempi) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_esempi, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        } else if (id == R.id.nav_home) {

            LinearLayout mainLayout = (LinearLayout) findViewById(R.id. main_container);
            LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View layout = inflater.inflate(R.layout.content_main, null);
            mainLayout.removeAllViews();
            mainLayout.addView(layout);

        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }
}

package com.ivancristina.navigazione；
导入android.content.Context；
导入android.content.Intent；
导入android.net.Uri；
导入android.os.Bundle；
导入android.support.design.widget.FloatingActionButton；
导入android.support.design.widget.NavigationView；
导入android.support.design.widget.Snackbar；
导入android.support.v4.view.GravityCompat；
导入android.support.v4.widget.DrawerLayout；
导入android.support.v7.app.ActionBarDrawerToggle；
导入android.support.v7.app.AppActivity；
导入android.support.v7.widget.Toolbar；
导入android.util.SparseBooleanArray；
导入android.view.LayoutInflater；
导入android.view.Menu；
导入android.view.MenuItem；
导入android.view.view；
导入android.widget.Button；
导入android.widget.ImageView；
导入android.widget.LinearLayout；
导入android.widget.ListView；
导入android.widget.Toast；
导入java.util.*；
公共类MainActivity扩展了AppCompatActivity
实现NavigationView.OnNavigationItemSelectedListener{
私人影像视图标识；
专用按钮github；
创建时受保护的void（Bundle savedInstanceState）{
super.onCreate（savedInstanceState）；
初始化（）；
setContentView（R.layout.activity_main）；
Toolbar Toolbar=（Toolbar）findViewById（R.id.Toolbar）；
设置支持操作栏（工具栏）；
getSupportActionBar（）.setTitle（“”）；
FloatingActionButton fab=（FloatingActionButton）findViewById（R.id.fab）；
fab.setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图）{
Snackbar.make（查看“替换为您自己的操作”，Snackbar.LENGTH\u LONG）
.setAction（“Action”，null）.show（）；
}
});
抽屉布局抽屉=（抽屉布局）findViewById（R.id.抽屉布局）；
ActionBarDrawerToggle切换=新建ActionBarDrawerToggle(
这，抽屉，工具栏，R.string.navigation\u drawer\u open，R.string.navigation\u drawer\u close）；
抽屉。设置抽屉定位器（开关）；
toggle.syncState（）；
NavigationView NavigationView=（NavigationView）findViewById（R.id.nav_视图）；
navigationView.setNavigationItemSelectedListener（此）；
}
私有void初始化（）{
logo=（ImageView）findviewbyd（R.id.logo）；
github=（按钮）findviewbyd（R.id.github）；
logo.setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图_v）{
showMessage（“OnClick”）；
}
});
github.setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图_v）{
startActivity（新意图（Intent.ACTION_视图，Uri.parse（“http://www.github.com/ivancristina")));
}
});
}
//自动创建
私有void showMessage（字符串）{
Toast.makeText（getApplicationContext（），_s，Toast.LENGTH_SHORT）.show（）；
}
私有int getRandom（int _minValue，int _maxValue）{
随机=新随机（）；
返回random.nextInt（_maxValue-_minValue+1）+_minValue；
}
公共阵列列表GetCheckEditionsToArray（列表视图_列表）{
ArrayList_result=新的ArrayList（）；
SparseBooleanArray _arr=_list.getCheckedItemPositions（）；
对于（int _iIdx=0；_iIdx<_arr.size（）；_iIdx++）{
如果（_arr.valueAt（_iIdx））
_结果.添加（（双）_arr.keyAt（_iIdx））；
}
返回结果；
}
@凌驾
public void onBackPressed（）{
抽屉布局抽屉=（抽屉布局）findViewById（R.id.抽屉布局）；
if（抽屉isDrawerOpen（重力压缩机启动））{
抽屉。关闭抽屉（重力压缩机启动）；
}否则{
super.onBackPressed（）；
}
}
@凌驾
公共布尔onCreateOptions菜单（菜单）{
//为菜单充气；这会将项目添加到操作栏（如果存在）。
getMenuInflater（）.充气（R.menu.main，menu）；
返回true；
}
@凌驾
公共布尔值onOptionsItemSelected（菜单项项）{
//处理操作栏项目单击此处。操作栏将
//自动处理Home/Up按钮上的点击，只要
//在AndroidManifest.xml中指定父活动时。
int id=item.getItemId（）；
//noinspection SimplifiableIf语句
if（id==R.id.action\u设置）{
返回true；
}
返回super.onOptionsItemSelected（项目）；
}
@SuppressWarnings（“StatementWithEmptyBody”）
@凌驾
公共布尔值onNavigationItemSelected（MenuItem项）{
//处理导航视图项单击此处。
int id=item.getItemId（）；
if（id==R.id.nav_公式）{
LinearLayout mainLayout=（LinearLayout）findViewById（R.id.main_容器）；
LayoutFlater充气器=（LayoutFlater）getSystemService（Context.LAYOUT\u充气器\u服务）；
视图布局=充气机。充气（R.layout.content\u公式，空）；
mainLayout.removeAllViews（）；
mainLayout.addView（布局）；
}else if（id==R.id.nav\u esempi）{
LinearLayout mainLayout=（LinearLayout）findViewById（R.id.main_容器）；
LayoutFlater充气器=（LayoutFlater）getSystemService（Context.LAYOUT\u充气器\u服务）；
视图布局=充气机。充气（R.layout.content\u esempi，null）；
mainLayout.removeAllViews（）；
mainLayout.addView（布局）；
}else if（id==R.id.nav_home）{
LinearLayout mainLayout=（LinearLayout）findViewById（R.id.main_容器）；
LayoutInflater充气机=（LayoutInflater）getSy