android.view.InflateException：二进制XML文件行＃6：错误输出类EditText

Question

我正在尝试将布局扩展为片段，并且有一个非常令人沮丧的错误

为什么只有EDITTEXT导致错误

我的片段布局代码usb_view.xml

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

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/editText"
        android:layout_alignParentTop="true"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true" />

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Begin"
        android:id="@+id/buttonStart"
        android:layout_below="@+id/editText"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:onClick="onClickStart"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Send"
        android:id="@+id/buttonSend"
        android:onClick="onClickSend"
        android:layout_below="@+id/editText"
        android:layout_toRightOf="@+id/buttonStart"
        android:layout_toEndOf="@+id/buttonStart" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/textView"
        android:layout_below="@+id/buttonSend"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_alignRight="@+id/editText"
        android:layout_alignEnd="@+id/editText"
        android:layout_alignParentBottom="true" />

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Stop"
        android:id="@+id/buttonStop"
        android:layout_below="@+id/editText"
        android:layout_toRightOf="@+id/buttonSend"
        android:layout_toEndOf="@+id/buttonSend"
        android:onClick="onClickStop"/>

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Clear"
        android:id="@+id/buttonClear"
        android:layout_below="@+id/editText"
        android:layout_toRightOf="@+id/buttonStop"
        android:layout_toEndOf="@+id/buttonStop"
        android:onClick="onClickClear"/>
</LinearLayout>

我的片段代码Usb.java

package com.example.rajat.blueusb
import android.app.Fragment;
import android.app.PendingIntent;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.hardware.usb.UsbDevice;
import android.hardware.usb.UsbDeviceConnection;
import android.hardware.usb.UsbManager;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

import com.felhr.usbserial.UsbSerialDevice;
import com.felhr.usbserial.UsbSerialInterface;

import java.io.UnsupportedEncodingException;
import java.util.HashMap;
import java.util.Map;

public class Usb extends Fragment {
    public Usb(){}


    public final String ACTION_USB_PERMISSION = "com.example.rajat.blueusb.USB_PERMISSION";
    Button startButton, sendButton, clearButton, stopButton;
    TextView textView;
    EditText editText;
    UsbManager usbManager;
    UsbDevice device;
    UsbSerialDevice serialPort;
    UsbDeviceConnection connection;

    UsbSerialInterface.UsbReadCallback mCallback = new UsbSerialInterface.UsbReadCallback() { //Defining a Callback which triggers whenever data is read.
        @Override
        public void onReceivedData(byte[] arg0) {
            String data = null;
            try {
                data = new String(arg0, "UTF-8");
                data.concat("/n");
                tvAppend(textView, data);
            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
            }


        }
    };
    private final BroadcastReceiver broadcastReceiver = new BroadcastReceiver() { //Broadcast Receiver to automatically start and stop the Serial connection.
        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equals(ACTION_USB_PERMISSION)) {
                boolean granted = intent.getExtras().getBoolean(UsbManager.EXTRA_PERMISSION_GRANTED);
                if (granted) {
                    connection = usbManager.openDevice(device);
                    serialPort = UsbSerialDevice.createUsbSerialDevice(device, connection);
                    if (serialPort != null) {
                        if (serialPort.open()) { //Set Serial Connection Parameters.
                            setUiEnabled(true);
                            serialPort.setBaudRate(9600);
                            serialPort.setDataBits(UsbSerialInterface.DATA_BITS_8);
                            serialPort.setStopBits(UsbSerialInterface.STOP_BITS_1);
                            serialPort.setParity(UsbSerialInterface.PARITY_NONE);
                            serialPort.setFlowControl(UsbSerialInterface.FLOW_CONTROL_OFF);
                            serialPort.read(mCallback);
                            tvAppend(textView,"Serial Connection Opened!\n");

                        } else {
                            Log.d("SERIAL", "PORT NOT OPEN");
                        }
                    } else {
                        Log.d("SERIAL", "PORT IS NULL");
                    }
                } else {
                    Log.d("SERIAL", "PERM NOT GRANTED");
                }
            } else if (intent.getAction().equals(UsbManager.ACTION_USB_DEVICE_ATTACHED)) {
                onClickStart(startButton);
            } else if (intent.getAction().equals(UsbManager.ACTION_USB_DEVICE_DETACHED)) {
                onClickStop(stopButton);

            }
        }

        ;
    };

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.usb_view, container, false);
        usbManager = (UsbManager) getActivity(). getSystemService(Context.USB_SERVICE);
        startButton = (Button)getView(). findViewById(R.id.buttonStart);
        sendButton = (Button)getView(). findViewById(R.id.buttonSend);
        clearButton = (Button)getView(). findViewById(R.id.buttonClear);
        stopButton = (Button)getView(). findViewById(R.id.buttonStop);
        editText = (EditText)getView().findViewById(R.id.editText);
        textView = (TextView)getView().findViewById(R.id.textView);
        setUiEnabled(false);
        IntentFilter filter = new IntentFilter();
        filter.addAction(ACTION_USB_PERMISSION);
        filter.addAction(UsbManager.ACTION_USB_DEVICE_ATTACHED);
        filter.addAction(UsbManager.ACTION_USB_DEVICE_DETACHED);
        getActivity().registerReceiver(broadcastReceiver, filter);

        return rootView;
    }

    public void setUiEnabled(boolean bool) {
        startButton.setEnabled(!bool);
        sendButton.setEnabled(bool);
        stopButton.setEnabled(bool);
        textView.setEnabled(bool);

    }

    public void onClickStart(View view) {

        HashMap<String, UsbDevice> usbDevices = usbManager.getDeviceList();
        if (!usbDevices.isEmpty()) {
            boolean keep = true;
            for (Map.Entry<String, UsbDevice> entry : usbDevices.entrySet()) {
                device = entry.getValue();
                int deviceVID = device.getVendorId();

                if (deviceVID ==1659)//Arduino Vendor ID
                {
                    PendingIntent pi = PendingIntent.getBroadcast(getActivity().getApplicationContext(), 0, new Intent(ACTION_USB_PERMISSION), 0);
                    usbManager.requestPermission(device, pi);
                    keep = false;

                    break;
                } else {
                    connection = null;
                    device = null;
                }

                if (!keep)
                    break;
            }
        }
    }

    public void onClickSend(View view) {
        String string = editText.getText().toString();
        serialPort.write(string.getBytes());
        tvAppend(textView, "\nData Sent : " + string + "\n");
    }

    public void onClickStop(View view) {
        setUiEnabled(false);
        serialPort.close();
        tvAppend(textView,"\nSerial Connection Closed! \n");

    }

    public void onClickClear(View view) {
        textView.setText(" ");
    }

    private void tvAppend(TextView tv, CharSequence text) {
        final TextView ftv = tv;
        final CharSequence ftext = text;

        getActivity().runOnUiThread(new Runnable() {
            @Override
            public void run() {
                ftv.append(ftext);
            }
        });
    }

}

我的MainActivity.java代码

package com.example.rajat.blueusb;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.view.View;
import android.support.design.widget.NavigationView;
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.Menu;
import android.view.MenuItem;
import android.app.Fragment;
import android.app.FragmentManager;
public class MainActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener {

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

        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.
        Fragment fragment=null;
        int id = item.getItemId();

        if (id == R.id.nav_usb) {
            fragment = new Usb();
        } else if (id == R.id.nav_blue) {
            fragment = new Bluetooth();

        }

        if (fragment != null) {
            FragmentManager fragmentManager = getFragmentManager();
            fragmentManager.beginTransaction()
                    .replace(R.id.content_main, fragment).commit();
        }

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

activity_main.xml中

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout 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:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start">

    <include
        layout="@layout/app_bar_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        app:headerLayout="@layout/nav_header_main"
        app:menu="@menu/activity_main_drawer" />


</android.support.v4.widget.DrawerLayout>

logcat的：

android.view.InflateException: Binary XML file line #6: Error inflating class EditText
   at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:763)
   at android.view.LayoutInflater.rInflate(LayoutInflater.java:806)
   at android.view.LayoutInflater.inflate(LayoutInflater.java:504)
   at android.view.LayoutInflater.inflate(LayoutInflater.java:414)
   at com.example.rajat.blueusb.Usb.onCreateView(Usb.java:109)
   at android.app.Fragment.performCreateView(Fragment.java:2069)
   at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:899)
   at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1072)

Answer 1

您无法同时将视图与左右对齐 如果您不想将EditText与左对齐：

   <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/editText"
        android:layout_alignParentTop="true"
        android:layout_alignParentStart="true" />

Answer 2

将import android.app.Fragment;更改为

import android.support.v4.app.Fragment;
public class Usb extends Fragment