java数据显示在logcat上，但我无法在android上显示

2jcobegt  于 2021-06-29  发布在  Java
关注(0)|答案(0)|浏览(221)

所以，我试图从我的hc05接收数据，它连接到我的arduino uno，从温度传感器dht11接收值。我做了一个应用程序，这样我就可以得到这些值，但它们只显示在logcat上，而不是在我的android屏幕上。
这是我的showinfoactivity，在这里我激活bt，它允许我显示不同的bt设备。

package com.example.temperaturaehumidade;

import android.Manifest;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Build;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

import java.util.ArrayList;
import java.util.UUID;

public class ShowInfoActivity extends AppCompatActivity{

    private static final String TAG = "ShowInfoActivity";

    private Button btnDiscoverability;
    private Button btnSearch;
    private Button btnONOFF;
    private Button btnConnect;
    private ListView listView;

    BluetoothAdapter mBluetoothAdapter;
    Button btnEnableDisable_Discoverable;

    BluetoothConnection mBluetoothConnection;

    TextView etSend;

    private static final UUID MY_UUID_INSECURE =
            UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");

    BluetoothDevice mBTDevice;

    public ArrayList<BluetoothDevice> mBTDevices = new ArrayList<>();

    public DeviceListAdapter mDeviceListAdapter;

    ListView lvNewDevices;

    // Create a BroadcastReceiver for ACTION_FOUND
    private final BroadcastReceiver mBroadcastReceiver1 = new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) {
            String action = intent.getAction();
            // When discovery finds a device
            if (action.equals(mBluetoothAdapter.ACTION_STATE_CHANGED)) {
                final int state = intent.getIntExtra(BluetoothAdapter.EXTRA_STATE, mBluetoothAdapter.ERROR);

                switch (state) {
                    case BluetoothAdapter.STATE_OFF:
                        Log.d(TAG, "onReceive: STATE OFF");
                        break;
                    case BluetoothAdapter.STATE_TURNING_OFF:
                        Log.d(TAG, "mBroadcastReceiver1: STATE TURNING OFF");
                        break;
                    case BluetoothAdapter.STATE_ON:
                        Log.d(TAG, "mBroadcastReceiver1: STATE ON");
                        break;
                    case BluetoothAdapter.STATE_TURNING_ON:
                        Log.d(TAG, "mBroadcastReceiver1: STATE TURNING ON");
                        break;
                }
            }
        }
    };

    /**
     * Broadcast Receiver for changes made to bluetooth states such as:
     * 1) Discoverability mode on/off or expire.
     */
    private final BroadcastReceiver mBroadcastReceiver2 = new BroadcastReceiver() {

        @Override
        public void onReceive(Context context, Intent intent) {
            final String action = intent.getAction();

            if (action.equals(BluetoothAdapter.ACTION_SCAN_MODE_CHANGED)) {

                int mode = intent.getIntExtra(BluetoothAdapter.EXTRA_SCAN_MODE, BluetoothAdapter.ERROR);

                switch (mode) {
                    //Device is in Discoverable Mode
                    case BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERABLE:
                        Log.d(TAG, "mBroadcastReceiver2: Discoverability Enabled.");
                        break;
                    //Device not in discoverable mode
                    case BluetoothAdapter.SCAN_MODE_CONNECTABLE:
                        Log.d(TAG, "mBroadcastReceiver2: Discoverability Disabled. Able to receive connections.");
                        break;
                    case BluetoothAdapter.SCAN_MODE_NONE:
                        Log.d(TAG, "mBroadcastReceiver2: Discoverability Disabled. Not able to receive connections.");
                        break;
                    case BluetoothAdapter.STATE_CONNECTING:
                        Log.d(TAG, "mBroadcastReceiver2: Connecting....");
                        break;
                    case BluetoothAdapter.STATE_CONNECTED:
                        Log.d(TAG, "mBroadcastReceiver2: Connected.");
                        break;
                }

            }
        }
    };

    /**
     * Broadcast Receiver for listing devices that are not yet paired
     * -Executed by btnDiscover() method.
     */
    private BroadcastReceiver mBroadcastReceiver3 = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            final String action = intent.getAction();
            Log.d(TAG, "onReceive: ACTION FOUND.");

            if (action.equals(BluetoothDevice.ACTION_FOUND)) {
                BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
                mBTDevices.add(device);
                Log.d(TAG, "onReceive: " + device.getName() + ": " + device.getAddress());
                mDeviceListAdapter = new DeviceListAdapter(context, R.layout.list_item, mBTDevices);
                lvNewDevices.setAdapter(mDeviceListAdapter);
            }
        }
    };

    /**
     * Broadcast Receiver that detects bond state changes (Pairing status changes)
     */
    private final BroadcastReceiver mBroadcastReceiver4 = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            final String action = intent.getAction();

            if (action.equals(BluetoothDevice.ACTION_BOND_STATE_CHANGED)) {
                BluetoothDevice mDevice = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
                //3 cases:
                //case1: bonded already
                if (mDevice.getBondState() == BluetoothDevice.BOND_BONDED) {
                    Log.d(TAG, "BroadcastReceiver: BOND_BONDED.");
                    //inside BroadcastReceiver4
                    mBTDevice = mDevice;
                }
                //case2: creating a bone
                if (mDevice.getBondState() == BluetoothDevice.BOND_BONDING) {
                    Log.d(TAG, "BroadcastReceiver: BOND_BONDING.");
                }
                //case3: breaking a bond
                if (mDevice.getBondState() == BluetoothDevice.BOND_NONE) {
                    Log.d(TAG, "BroadcastReceiver: BOND_NONE.");
                }
            }
        }
    };

    @Override
    protected void onDestroy() {
        Log.d(TAG, "onDestroy: called.");
        super.onDestroy();
        unregisterReceiver(mBroadcastReceiver1);
        unregisterReceiver(mBroadcastReceiver2);
        unregisterReceiver(mBroadcastReceiver3);
        unregisterReceiver(mBroadcastReceiver4);
    }

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

        btnConnect=findViewById(R.id.id_connect);
        btnDiscoverability = findViewById(R.id.id_Discoverability);
        btnONOFF = findViewById(R.id.id_ONOFF);
        btnSearch = findViewById(R.id.id_search);
        lvNewDevices = (ListView) findViewById(R.id.lvNewDevices);
        etSend = (TextView) findViewById(R.id.txtReceive);
        mBTDevices = new ArrayList<>();

        //Broadcasts when bond state changes (ie:pairing)
        IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_BOND_STATE_CHANGED);
        registerReceiver(mBroadcastReceiver4, filter);

        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

        lvNewDevices.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int i, long id) {
                //first cancel discovery because its very memory intensive.
                mBluetoothAdapter.cancelDiscovery();

                Log.d(TAG, "onItemClick: You Clicked on a device.");
                String deviceName = mBTDevices.get(i).getName();
                String deviceAddress = mBTDevices.get(i).getAddress();

                Log.d(TAG, "onItemClick: deviceName = " + deviceName);
                Log.d(TAG, "onItemClick: deviceAddress = " + deviceAddress);

                //create the bond.
                //NOTE: Requires API 17+? I think this is JellyBean
                if(Build.VERSION.SDK_INT > Build.VERSION_CODES.JELLY_BEAN_MR2){
                    Log.d(TAG, "Trying to pair with " + deviceName);
                    mBTDevices.get(i).createBond();

                    mBTDevice = mBTDevices.get(i);
                    mBluetoothConnection = new BluetoothConnection(ShowInfoActivity.this);
                }

            }
        });

        btnConnect.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                startConnection();

            }
        });

        btnONOFF.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Log.d(TAG, "onClick: enabling/disabling bluetooth.");
                enableDisableBT();
            }
        });

        btnDiscoverability.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Log.d(TAG, "btnEnableDisable_Discoverable: Making device discoverable for 300 seconds.");
                enableDisableDiscoverability();

            }
        });
        btnSearch.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Log.d(TAG, "btnDiscover: Looking for unpaired devices.");
                enableDiscover();
            }
        });

    }

    //create method for starting connection
//***remember the conncction will fail and app will crash if you haven't paired first
    public void startConnection(){
        startBTConnection(mBTDevice,MY_UUID_INSECURE);
    }

    /**
     * starting chat service method
     */
    public void startBTConnection(BluetoothDevice device, UUID uuid){
        Log.d(TAG, "startBTConnection: Initializing RFCOM Bluetooth Connection.");

        mBluetoothConnection.startClient(device,uuid);
    }

    public void enableDisableBT() {
        if (mBluetoothAdapter == null) {
            Log.d(TAG, "enableDisableBT: Does not have BT capabilities.");
        }
        if (!mBluetoothAdapter.isEnabled()) {
            Log.d(TAG, "enableDisableBT: enabling BT.");
            Intent enableBTIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
            startActivity(enableBTIntent);

            IntentFilter BTIntent = new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED);
            registerReceiver(mBroadcastReceiver1, BTIntent);
        }
        if (mBluetoothAdapter.isEnabled()) {
            Log.d(TAG, "enableDisableBT: disabling BT.");
            mBluetoothAdapter.disable();

            IntentFilter BTIntent = new IntentFilter(BluetoothAdapter.ACTION_STATE_CHANGED);
            registerReceiver(mBroadcastReceiver1, BTIntent);
        }

    }

    public void enableDisableDiscoverability() {

        Intent discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
        discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);
        startActivity(discoverableIntent);

        IntentFilter intentFilter = new IntentFilter(mBluetoothAdapter.ACTION_SCAN_MODE_CHANGED);
        registerReceiver(mBroadcastReceiver2, intentFilter);
    }

    public void enableDiscover() {
        if (mBluetoothAdapter.isDiscovering()) {
            mBluetoothAdapter.cancelDiscovery();
            Log.d(TAG, "btnDiscover: Canceling discovery.");

            //check BT permissions in manifest
            checkBTPermissions();

            mBluetoothAdapter.startDiscovery();
            IntentFilter discoverDevicesIntent = new IntentFilter(BluetoothDevice.ACTION_FOUND);
            registerReceiver(mBroadcastReceiver3, discoverDevicesIntent);
        }
        if (!mBluetoothAdapter.isDiscovering()) {

            //check BT permissions in manifest
            checkBTPermissions();

            mBluetoothAdapter.startDiscovery();
            IntentFilter discoverDevicesIntent = new IntentFilter(BluetoothDevice.ACTION_FOUND);
            registerReceiver(mBroadcastReceiver3, discoverDevicesIntent);
        }

    }

    /**
     * This method is required for all devices running API23+
     * Android must programmatically check the permissions for bluetooth. Putting the proper permissions
     * in the manifest is not enough.
     * <p>
     * NOTE: This will only execute on versions > LOLLIPOP because it is not needed otherwise.
     */

    private void checkBTPermissions() {
        if (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP) {
            int permissionCheck = this.checkSelfPermission("Manifest.permission.ACCESS_FINE_LOCATION");
            permissionCheck += this.checkSelfPermission("Manifest.permission.ACCESS_COARSE_LOCATION");
            if (permissionCheck != 0) {

                this.requestPermissions(new String[]{Manifest.permission.ACCESS_FINE_LOCATION, Manifest.permission.ACCESS_COARSE_LOCATION}, 1001); //Any number
            }
        } else {
            Log.d(TAG, "checkBTPermissions: No need to check permissions. SDK version < LOLLIPOP.");
        }
    }

}```

蓝牙连接

package com.example.temperaturaehumidade;

import android.app.ProgressDialog;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothServerSocket;
import android.bluetooth.BluetoothSocket;
import android.content.Context;
import android.util.Log;
import android.widget.TextView;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.Charset;
import java.util.UUID;

/**
 * Created by User on 12/21/2016.
 */

public class BluetoothConnection {
    private static final String TAG = "BluetoothConnectionServ";

    private static final String appName = "MYAPP";

    private static final UUID MY_UUID_INSECURE =
            UUID.fromString("00001101-0000-1000-8000-00805f9b34fb");

    private final BluetoothAdapter mBluetoothAdapter;
    Context mContext;

    private AcceptThread mInsecureAcceptThread;

    private ConnectThread mConnectThread;
    private TextView mTxtReceive;
    private BluetoothDevice mmDevice;
    private UUID deviceUUID;
    ProgressDialog mProgressDialog;

    private ConnectedThread mConnectedThread;

    public BluetoothConnection(Context context) {
        mContext = context;
        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
        start();
    }

     Finally the ConnectedThread which is responsible for maintaining the BTConnection, Sending the data, and
     receiving incoming data through input/output streams respectively.
   **/
    private class ConnectedThread extends Thread {
        private final BluetoothSocket mmSocket;
        private final InputStream mmInStream;
        private final OutputStream mmOutStream;

        private class ReadInput implements Runnable {

            private boolean bStop = false;
            private Thread t;

            public ReadInput() {
                t = new Thread(this, "Input Thread");
                t.start();
            }

            public boolean isRunning() {
                return t.isAlive();
            }

            @Override
            public void run() {
                InputStream inputStream;

                try {
                    inputStream = mmSocket.getInputStream();
                    while (!bStop) {
                        byte[] buffer = new byte[256];
                        if (inputStream.available() > 0) {
                            inputStream.read(buffer);
                            int i = 0;
                            /*
                             * This is needed because new String(buffer) is taking the entire buffer i.e. 256 chars on Android 2.3.4 http://stackoverflow.com/a/8843462/1287554
                             */
                            for (i = 0; i < buffer.length && buffer[i] != 0; i++) {
                            }
                            final String strInput = new String(buffer, 0, i);

                            /*
                             * If checked then receive text, better design would probably be to stop thread if unchecked and free resources, but this is a quick fix
                             */

                        }
                        Thread.sleep(500);
                    }
                } catch (IOException e) {
// TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (InterruptedException e) {
// TODO Auto-generated catch block
                    e.printStackTrace();
                }

            }

            public void stop() {
                bStop = true;
            }

        }

        public ConnectedThread(BluetoothSocket socket) {
            Log.d(TAG, "ConnectedThread: Starting.");

            mmSocket = socket;
            InputStream tmpIn = null;
            OutputStream tmpOut = null;

            //dismiss the progressdialog when connection is established
            try{
                mProgressDialog.dismiss();
            }catch (NullPointerException e){
                e.printStackTrace();
            }

            try {
                tmpIn = mmSocket.getInputStream();
                tmpOut = mmSocket.getOutputStream();
            } catch (IOException e) {
                e.printStackTrace();
            }

            mmInStream = tmpIn;
            mmOutStream = tmpOut;
        }

        public void run(){
            byte[] buffer = new byte[1024];  // buffer store for the stream

            int bytes; // bytes returned from read()

            // Keep listening to the InputStream until an exception occurs
            while (true) {
                // Read from the InputStream
                try {
                    bytes = mmInStream.read(buffer);
                    String incomingMessage = new String(buffer, 0, bytes);
                    Log.d(TAG, "InputStream: " + incomingMessage);
                } catch (IOException e) {
                    Log.e(TAG, "write: Error reading Input Stream. " + e.getMessage() );
                    break;
                }
            }
        }

        //Call this from the main activity to send data to the remote device
        public void write(byte[] bytes) {
            String text = new String(bytes, Charset.defaultCharset());
            Log.d(TAG, "write: Writing to outputstream: " + text);
            try {
                mmOutStream.write(bytes);
            } catch (IOException e) {
                Log.e(TAG, "write: Error writing to output stream. " + e.getMessage() );
            }
        }

        /* Call this from the main activity to shutdown the connection */
        public void cancel() {
            try {
                mmSocket.close();
            } catch (IOException e) { }
        }
    }

    private void connected(BluetoothSocket mmSocket, BluetoothDevice mmDevice) {
        Log.d(TAG, "connected: Starting.");

        // Start the thread to manage the connection and perform transmissions
        mConnectedThread = new ConnectedThread(mmSocket);
        mConnectedThread.start();
    }

    /**
     * Write to the ConnectedThread in an unsynchronized manner
     *
     * @param out The bytes to write
     * @see ConnectedThread#write(byte[])
     */
    public void write(byte[] out) {
        // Create temporary object
        ConnectedThread r;

        // Synchronize a copy of the ConnectedThread
        Log.d(TAG, "write: Write Called.");
        //perform the write
        mConnectedThread.write(out);
    }

}

xml文件：

<?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="match_parent"
    android:background="@color/black">

        <Button
            android:id="@+id/id_ONOFF"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_margin="20dp"
            android:gravity="center_vertical|center_horizontal"
            android:hint="ON/OFF"
            android:textColorHint="@color/white" />
        <Button
            android:id="@+id/id_Discoverability"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="Discoverability"
            android:layout_margin="20dp"
            android:gravity="center_vertical|center_horizontal"
            android:textColorHint="@color/white"/>

        <Button
            android:id="@+id/id_search"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="Search"
            android:layout_margin="20dp"
            android:gravity="center_vertical|center_horizontal"
            android:textColorHint="@color/white"/>

        <Button
            android:id="@+id/id_connect"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_margin="20dp"
            android:gravity="center_vertical|center_horizontal"
            android:hint="Connect"
            android:textColorHint="@color/white" />

    <ListView
        android:layout_below="@id/id_connect"
        android:layout_width="match_parent"
        android:layout_height="150dp"
        android:id="@+id/lvNewDevices"/>

    <TextView
            android:id="@+id/txtReceive"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:background="#eeeeee"
            android:hint="Message shows up here ..." />

</LinearLayout>

logcat公司
这些值出现在logcat上而不是android屏幕上，有人能帮我吗？非常感谢。为了给你提供信息，我在youtube上关注了这个家伙关于如何建立蓝牙连接的视频https://www.youtube.com/watch?v=y8r2c86biuc&list=plgcyzuzkibe8khmzpp6jitz2jxtgwqdh2

JavaandroidlogcatbluetoothLayout

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