在android studio中打开一个片段内的片段

Question

我有一个框架布局。我在其中设置了扫描仪视图。

<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/white"
android:orientation="vertical"
android:id="@+id/root"
android:padding="10dp">

<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.budiyev.android.codescanner.CodeScannerView
        android:id="@+id/scanner_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:autoFocusButtonColor="@android:color/white"
        app:autoFocusButtonVisible="true"
        app:flashButtonColor="@android:color/white"
        app:flashButtonVisible="true"
        app:frameColor="@android:color/white"
        app:frameCornersSize="50dp"
        app:frameCornersRadius="0dp"
        app:frameAspectRatioWidth="1"
        app:frameAspectRatioHeight="1"
        app:frameSize="0.75"
        app:frameThickness="2dp"
        app:maskColor="#77000000"/>
</FrameLayout>
</androidx.coordinatorlayout.widget.CoordinatorLayout>

现在我正在另一个片段上打开它，但我不想这样做。我想点击按钮打开它

 @BindView(R.id.start_scan)
 ImageButton startScan;

public void bindListners()
{
   startScan.setOnClickListener(startScanning);
}

private final View.OnClickListener startScanning = v -> {

     if(v.getId()==R.id.start_scan){
       //here I want to call it
     }

}

更新 1 MainActivity

我的MainActivity 中还有一些其他片段。以下是我的整个主要活动代码

public class MainActivity extends AppCompatActivity
    implements NavigationView.OnNavigationItemSelectedListener {
//fragments
ScanFragment scanFragment = null;
NewFormFragment mNewFormFragment = null;
InstallationListFragment mInstallationListFragment = null;
ProgressFragment progressFragment = null;
boolean quitPress = false;

NavigationView navigationView;

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

    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) {
        @Override
        public void onDrawerClosed(View drawerView) {
            super.onDrawerClosed(drawerView);
        }

        @Override
        public void onDrawerOpened(View drawerView) {
            super.onDrawerOpened(drawerView);
        }

        @Override
        public void onDrawerSlide(View drawerView, float slideOffset) {
            super.onDrawerSlide(drawerView, slideOffset);
            Common.hideSoftKeyboard(MainActivity.this);
        }

        @Override
        public void onDrawerStateChanged(int newState) {
            super.onDrawerStateChanged(newState);
        }
    };
    drawer.setDrawerListener(toggle);
    toggle.syncState();

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

    mNewFormFragment = new NewFormFragment();
    FragmentManager fragmentManager = getFragmentManager();
    fragmentManager.beginTransaction()
            .setCustomAnimations(android.R.animator.fade_in, android.R.animator.fade_out, android.R.animator.fade_in, android.R.animator.fade_out)
            .replace(R.id.fragment_container, mNewFormFragment, Constants.FRAGMENTS_NEW_FORM_TAG)
            .commit();
    fragmentManager.executePendingTransactions();
    navigationView.setCheckedItem(R.id.new_form);

    View headerView = navigationView.getHeaderView(0);
    TextView t = (TextView) headerView.findViewById(R.id.user_name);
    t.setText(Common.SharedPreferenceHelper.getSharedPreference(this, getString(R.string.user_name_key), ""));

    Log.d("zaidi","auth = "+Common.getAuthKey(this));

}

@Override
public void onBackPressed() {
    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    if (drawer.isDrawerOpen(GravityCompat.START)) {
        drawer.closeDrawer(GravityCompat.START);
    }
    FragmentManager manager = getFragmentManager();
    if (manager.getBackStackEntryCount() == 0 && !quitPress) {
        Toast.makeText(MainActivity.this, "Press again to quit", Toast.LENGTH_SHORT).show();
        quitPress = true;
    } else {
        quitPress = false;
        try {
            super.onBackPressed();
        } catch (Exception e) {

        }
    }
    if (manager.getBackStackEntryCount() > 0) {
        String backStack = manager.getBackStackEntryAt(manager.getBackStackEntryCount() - 1).getName();
        setNavigationItem(getMenuIdByTag(backStack));
    } else {
        setNavigationItem(getMenuIdByTag(Constants.FRAGMENTS_NEW_FORM_TAG));
    }
}

private void setNavigationItem(int id) {
    try {
        navigationView.getMenu().getItem(id).setChecked(true);
    } catch (Exception e) {
        e.printStackTrace();
    }
}

private int getMenuIdByTag(String tag) {
    switch (tag) {
        case Constants.FRAGMENTS_NEW_FORM_TAG: {
            return 0;
        }
        case Constants.FRAGMENT_INSTALLATIONS_TAG: {
            return 1;
        }
        case Constants.FRAGMENT_INSTALLATION_PROGRESS_TAG: {
            return 2;
        }
        case Constants.FRAGMENT_SETTINGS_TAG: {
            return 3;
        }
        default: {
            return -1;
        }
    }
}

@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();
    Common.hideSoftKeyboard(MainActivity.this);
    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        SettingsFragment myFragment = (SettingsFragment) getFragmentManager().findFragmentByTag(Constants.FRAGMENT_SETTINGS_TAG);
        if (myFragment != null && myFragment.isVisible()) {
            // add your code here
        } else {
            FragmentManager fragmentManager = getFragmentManager();
            fragmentManager.beginTransaction()
                    .setCustomAnimations(android.R.animator.fade_in, android.R.animator.fade_out, android.R.animator.fade_in, android.R.animator.fade_out)
                    .replace(R.id.fragment_container, new SettingsFragment(), Constants.FRAGMENT_SETTINGS_TAG)
                    .addToBackStack(Constants.FRAGMENT_SETTINGS_TAG).commit();
            fragmentManager.executePendingTransactions();
            setNavigationItem(getMenuIdByTag(Constants.FRAGMENT_SETTINGS_TAG));
        }
        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.new_form) {
        NewFormFragment myFragment = (NewFormFragment) getFragmentManager().findFragmentByTag(Constants.FRAGMENTS_NEW_FORM_TAG);
        if (myFragment != null && myFragment.isVisible() && this.getTitle() == "New Form") {
            // add your code here

        } else if (mNewFormFragment == null) {
            mNewFormFragment = new NewFormFragment();
        }
        FragmentManager fragmentManager = getFragmentManager();
        fragmentManager.beginTransaction()
                .setCustomAnimations(android.R.animator.fade_in, android.R.animator.fade_out, android.R.animator.fade_in, android.R.animator.fade_out)
                .replace(R.id.fragment_container, mNewFormFragment, Constants.FRAGMENTS_NEW_FORM_TAG)
                .addToBackStack(Constants.FRAGMENTS_NEW_FORM_TAG).commit();
        fragmentManager.executePendingTransactions();
    } else if (id == R.id.action_settings) {
        SettingsFragment myFragment = (SettingsFragment) getFragmentManager().findFragmentByTag(Constants.FRAGMENT_SETTINGS_TAG);
        if (myFragment != null && myFragment.isVisible()) {
            // add your code here
        } else {
            FragmentManager fragmentManager = getFragmentManager();
            fragmentManager.beginTransaction()
                    .setCustomAnimations(android.R.animator.fade_in, android.R.animator.fade_out, android.R.animator.fade_in, android.R.animator.fade_out)
                    .replace(R.id.fragment_container, new SettingsFragment(), Constants.FRAGMENT_SETTINGS_TAG)
                    .addToBackStack(Constants.FRAGMENT_SETTINGS_TAG).commit();
            fragmentManager.executePendingTransactions();
        }
    } else if (id == R.id.installations) {
        InstallationListFragment myFragment = (InstallationListFragment) getFragmentManager().findFragmentByTag(Constants.FRAGMENT_INSTALLATIONS_TAG);
        if (myFragment != null && myFragment.isVisible()) {
            // add your code here
        } else {
            if (this.mInstallationListFragment == null) {
                this.mInstallationListFragment = new InstallationListFragment();
            }
            FragmentManager fragmentManager = getFragmentManager();
            fragmentManager.beginTransaction()
                    .setCustomAnimations(android.R.animator.fade_in, android.R.animator.fade_out, android.R.animator.fade_in, android.R.animator.fade_out)
                    .replace(R.id.fragment_container, mInstallationListFragment, Constants.FRAGMENT_INSTALLATIONS_TAG)
                    .addToBackStack(Constants.FRAGMENT_INSTALLATIONS_TAG).commit();
            fragmentManager.executePendingTransactions();
        }
    } else if (id == R.id.progress) {
        ProgressFragment myFragment = (ProgressFragment) getFragmentManager().findFragmentByTag(Constants.FRAGMENT_INSTALLATION_PROGRESS_TAG);
        if (myFragment != null && myFragment.isVisible()) {
            // add your code here
        } else {
            if (this.progressFragment == null) {
                this.progressFragment = new ProgressFragment();
            }
            FragmentManager fragmentManager = getFragmentManager();
            fragmentManager.beginTransaction()
                    .setCustomAnimations(android.R.animator.fade_in, android.R.animator.fade_out, android.R.animator.fade_in, android.R.animator.fade_out)
                    .replace(R.id.fragment_container, progressFragment, Constants.FRAGMENT_INSTALLATION_PROGRESS_TAG)
                    .addToBackStack(Constants.FRAGMENT_INSTALLATION_PROGRESS_TAG).commit();
            fragmentManager.executePendingTransactions();
        }
    }

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


@Override
public void onRequestPermissionsResult(int requestCode,
                                       String permissions[], int[] grantResults) {
    switch (requestCode) {
        case Constants.MY_PERMISSIONS_LOCATION_REQUEST_CODE: {
            // If request is cancelled, the result arrays are empty.
            if (grantResults.length > 0
                    && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                // permission was granted, yay! Do the
                // contacts-related task you need to do.
                mNewFormFragment.getGPSLocation();

            } else {

                // permission denied, boo! Disable the
                // functionality that depends on this permission.
            }
            return;
        }

        case Constants.MY_PERMISSIONS_CAMERA_REQUEST_CODE: {
            // If request is cancelled, the result arrays are empty.
            if (grantResults.length > 0
                    && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                // permission was granted, yay! Do the
                // contacts-related task you need to do.
                if (mNewFormFragment.checkStoragePermission()) {
                    mNewFormFragment.openCamera();
                }

            } else {

                // permission denied, boo! Disable the
                // functionality that depends on this permission.
            }
            return;
        }

        case Constants.MY_PERMISSIONS_STORAGE_REQUEST_FOR_CAMERA_CODE: {
            // If request is cancelled, the result arrays are empty.
            if (grantResults.length > 0
                    && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

                // permission was granted, yay! Do the

                mNewFormFragment.openCamera();

            } else {

                // permission denied, boo! Disable the
                // functionality that depends on this permission.
            }
            return;
        }
        case RefreshRefrenceNumber.WRITE_PERMISSION_REQUEST_CODE_REF_NO: {
            // If request is cancelled, the result arrays are empty.
            if (grantResults.length > 0
                    && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                // permission was granted, yay! Do the
                RefreshRefrenceNumber.refreshManagerInstance(this).refreshReferenceNumber();
                RefreshMeterNumber.refreshManagerInstance(this).refreshMetetNumber();
                RefreshImsiNumber.refreshManagerInstance(this).refreshImsiNumber();
            } else {

                // permission denied, boo! Disable the
                // functionality that depends on this permission.
            }
            return;
        }
    }
}}

任何帮助将不胜感激。

Answer 1

当我必须管理多个片段，它们的动作可以在一个片段中启动另一个片段时，这是我使用的架构： 管理 Fragment 启动的父 Activity，我们称之为 MainActivity： 和框架： Fragment1 和 Fragment2：代码如下：

主活动

           public class MAinActivity extends AppCompatActivity  implements
                 Fragment1.ActionListener,
                 Fragment2.ActionListener {
                 private FragmentManager manager=null;
                
            @Override
            protected void onCreate(Bundle savedInstanceState) {
                  super.onCreate(savedInstanceState);
                  setContentView(R.layout.activity_main);
  
                  manager=getSupportFragmentManager();

               //you should launch one fragment at startup
               changefrag(new Fragment1());

       }
       public void changefrag(Fragment frag) {

          manager = getSupportFragmentManager();

         if (!manager.beginTransaction().isEmpty()) {
          manager.beginTransaction().detach(frag);
         }
       manager.beginTransaction()
            .replace(R.id.activity_main_frame_layout, frag).commit();

      }



    /**
     *
     *To start Fragment1 when action is perform in Fragment2
     */
    @Override
    public void onFragment1() {
     changefrag(new Fragment1());
    }

     /**
      * to start frament 2 when action is performe inside Fragment1
      * @param id
      */


     @Override
     public void onFragment2() {
        changefrag(new Fragment2());
     }
 }

片段1：

 public class Fragment1 extends Fragment {
    private ActionListener listerner;

   public Fragment1() {
    // Required empty public constructor
    }

   public static Fragment1 newInstance() {
    Fragment1 fragment = new Fragment1();
 
    return fragment;
    }

   @Override
   public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
   listener=(ActionListener)getActivity();
     
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
        View view=inflater.inflate(R.layout.fragment_1, container, false);
      view.findViewById(R.id.start_frag2).setOnClickListener(new 
           View.OnClickListener() {
           @Override
           public void onClick(View view) {

            listener.onFragment2();
        }
    });
    return view;
  
    }
     public interface ActionListener{
       void onFragment2();
   
     }
   }
    

片段2：

 public class Fragment2 extends Fragment {
    private ActionListener listerner;

   public Fragment1() {
    // Required empty public constructor
    }

   public static Fragment2 newInstance() {
    Fragment2 fragment = new Fragment2();
 
    return fragment;
    }

   @Override
   public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
   listener=(ActionListener)getActivity();
     
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
        View view=inflater.inflate(R.layout.fragment_2, container, false);
      view.findViewById(R.id.start_frag1).setOnClickListener(new 
           View.OnClickListener() {
           @Override
           public void onClick(View view) {

            listener.onFragment1();
        }
    });
    return view;
  
    }
     public interface ActionListener{
       void onFragment1();
   
     }
   }

Answer 2

单击按钮时执行此操作

   Fragment someFragment = new SomeFragment(); 
    FragmentTransaction transaction = getFragmentManager().beginTransaction();
    transaction.replace(R.id.fragment_container, someFragment ); 
// give your fragment container id in first parameter
    transaction.addToBackStack(null);  
// if written, this transaction will be added to backstack
    transaction.commit();