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使用executeOnExcecutor的java AsyncTask使用太多内存,导致UI冻结

我被指示使用AsyncTask,因为多线程仍然导致我的应用程序冻结。我认为我没有正确使用AsyncTask。在我在线看到的示例中,他们不必调用方法Complete()

http://examples.javacodegeeks.com/安卓/core/os/asynctask/安卓-asynctask-example/

我在READ_消息的情况下调用Complete(),结果它使我的应用程序崩溃。我不确定需要采取什么步骤来修复此代码。使用executeOnExcecutor的AsyncTask使用太多内存,导致UI冻结。我认为我调用“Complete()”的方式不正确

BluetoothChat完整代码

/**
 * This is the main Activity that displays the current chat session.
 */
@SuppressLint("HandlerLeak")
public class BluetoothChat extends Activity {
    // Debugging
    private static final String TAG = "BluetoothChat";
    private static final boolean D = true;

    // Message types sent from the BluetoothChatService Handler
    public static final int MESSAGE_STATE_CHANGE = 1;
    public static final int MESSAGE_READ = 2;
    public static final int MESSAGE_WRITE = 3;
    public static final int MESSAGE_DEVICE_NAME = 4;
    public static final int MESSAGE_TOAST = 5;
    public static final int THREAD_POOL_SIZE = Integer.MAX;

    // Key names received from the BluetoothChatService Handler
    public static final String DEVICE_NAME = "device_name";
    public static final String TOAST = "toast";

    // Intent request codes
    private static final int REQUEST_CONNECT_DEVICE_SECURE = 1;
    private static final int REQUEST_CONNECT_DEVICE_INSECURE = 2;
    private static final int REQUEST_ENABLE_BT = 3;

    // Layout Views
    private ListView mConversationView;
    private EditText mOutEditText;
    private Button mSendButton;
    public Button mFunctionButton;
    public Button seizureResult;
    public double [][]stored = new double[8000][1];
    public static HjorthClass finalValue;
    public int a;
    public Handler handler;
    public static boolean potato = false;
    public String transfer;
    public boolean bool;

    // Name of the connected device
    private String mConnectedDeviceName = null;
    // Array adapter for the conversation thread
    private ArrayAdapter<String> mConversationArrayAdapter;
    // String buffer for outgoing messages
    private StringBuffer mOutStringBuffer;
    // Local Bluetooth adapter
    private BluetoothAdapter mBluetoothAdapter = null;
    // Member object for the chat services
    private BluetoothChatService mChatService = null;


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getWindow().requestFeature(Window.FEATURE_ACTION_BAR);
        if(D) Log.e(TAG, "+++ ON CREATE +++");

        // Set up the window layout
        setContentView(R.layout.main);
        setTitle("Seizure Detection Helmet Application");

        handler = new Handler();
        mFunctionButton = (Button)findViewById(R.id.functions);
        seizureResult  = (Button)findViewById(R.id.SeizureResult);

        mFunctionButton.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {

                Intent z = new Intent(BluetoothChat.this, MainActivity.class);
                startActivity(z);
            }

        });
        seizureResult.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v){
                Toast.makeText(getApplicationContext(), "Value =="+bool, Toast.LENGTH_LONG).show();
        }
        });

        // Get local Bluetooth adapter
        mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

        // If the adapter is null, then Bluetooth is not supported
        if (mBluetoothAdapter == null) {
            Toast.makeText(this, "Bluetooth is not available", Toast.LENGTH_LONG).show();
            finish();
            return;
        }
    }

    @Override
    public void onStart() {
        super.onStart();
        if(D) Log.e(TAG, "++ ON START ++");

        // If BT is not on, request that it be enabled.
        // setupChat() will then be called during onActivityResult
        if (!mBluetoothAdapter.isEnabled()) {
            Intent enableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
            startActivityForResult(enableIntent, REQUEST_ENABLE_BT);
        // Otherwise, setup the chat session
        } else {
            if (mChatService == null) setupChat();
        }
    }

    @Override
    public synchronized void onResume() {
        super.onResume();
        if(D) Log.e(TAG, "+ ON RESUME +");

        // Performing this check in onResume() covers the case in which BT was
        // not enabled during onStart(), so we were paused to enable it...
        // onResume() will be called when ACTION_REQUEST_ENABLE activity returns.
        if (mChatService != null) {
            // Only if the state is STATE_NONE, do we know that we haven't started already
            if (mChatService.getState() == BluetoothChatService.STATE_NONE) {
              // Start the Bluetooth chat services
              mChatService.start();
            }
        }
    }

    private void setupChat() {
        Log.d(TAG, "setupChat()");

        // Initialize the array adapter for the conversation thread
        mConversationArrayAdapter = new ArrayAdapter<String>(this, R.layout.message);
        mConversationView = (ListView) findViewById(R.id.in);
        mConversationView.setAdapter(mConversationArrayAdapter);

        // Initialize the compose field with a listener for the return key
        mOutEditText = (EditText) findViewById(R.id.edit_text_out);
        mOutEditText.setOnEditorActionListener(mWriteListener);

        // Initialize the send button with a listener that for click events
        mSendButton = (Button) findViewById(R.id.button_send);
        mSendButton.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                // Send a message using content of the edit text widget
                TextView view = (TextView) findViewById(R.id.edit_text_out);
                String message = view.getText().toString();
                sendMessage(message);
            }
        });

        // Initialize the BluetoothChatService to perform bluetooth connections
        mChatService = new BluetoothChatService(this, mHandler);

        // Initialize the buffer for outgoing messages
        mOutStringBuffer = new StringBuffer("");
    }

    @Override
    public synchronized void onPause() {
        super.onPause();
        if(D) Log.e(TAG, "- ON PAUSE -");
    }

    @Override
    public void onStop() {
        super.onStop();
        if(D) Log.e(TAG, "-- ON STOP --");
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        // Stop the Bluetooth chat services
        if (mChatService != null) mChatService.stop();
        if(D) Log.e(TAG, "--- ON DESTROY ---");
    }

    private void ensureDiscoverable() {
        if(D) Log.d(TAG, "ensure discoverable");
        if (mBluetoothAdapter.getScanMode() !=
            BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERABLE) {
            Intent discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE);
            discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300);
            startActivity(discoverableIntent);
        }
    }

    private class ProcessData extends AsyncTask<Boolean, Void, Boolean>
    {

        @Override
        protected Boolean doInBackground(Boolean... params) 
        {
        for(int a = 0; a<8000; a++)
        {
            try
            {
            if(transfer == null)
            {
                transfer = "0";
            }
            double[] convert = new double[1];
            for(int z=0; z <1;z++)
            {
            convert[z]= Double.parseDouble(transfer);
            }
            for(int j=0; j<1;j++)
            {
            stored[a][j]= convert[j];
            }
            }
            catch(NumberFormatException e)
            {
            }
            }
            finalValue = new HjorthClass(stored);
            bool = finalValue.returnSum();
            return bool;
        }
    }

    private final ExecutorService mThreadPoolExecutor = Executors.newFixedThreadPool(THREAD_POOL_SIZE);

    public void Complete()
    {
        ProcessData task = new ProcessData();
        task.executeOnExecutor(mThreadPoolExecutor,bool);
    }


    /**
     * Sends a message.
     * @param message  A string of text to send.
     */
    private void sendMessage(String message) {
        // Check that we're actually connected before trying anything
        if (mChatService.getState() != BluetoothChatService.STATE_CONNECTED) {
            Toast.makeText(this, R.string.not_connected, Toast.LENGTH_SHORT).show();
            return;
        }

        // Check that there's actually something to send
        if (message.length() > 0) {
            // Get the message bytes and tell the BluetoothChatService to write
            byte[] send = message.getBytes();
            mChatService.write(send);

            // Reset out string buffer to zero and clear the edit text field
            mOutStringBuffer.setLength(0);
            mOutEditText.setText(mOutStringBuffer);
        }
    }

    // The action listener for the EditText widget, to listen for the return key
    private TextView.OnEditorActionListener mWriteListener =
        new TextView.OnEditorActionListener() {
        public boolean onEditorAction(TextView view, int actionId, KeyEvent event) {
            // If the action is a key-up event on the return key, send the message
            if (actionId == EditorInfo.IME_NULL && event.getAction() == KeyEvent.ACTION_UP) {
                String message = view.getText().toString();
                sendMessage(message);
            }
            if(D) Log.i(TAG, "END onEditorAction");
            return true;
        }
    };




   /** private final void setStatus(int resId) {
        final ActionBar actionBar = getActionBar();
        actionBar.setSubtitle(resId);
    }

    private final void setStatus(CharSequence subTitle) {
        final ActionBar actionBar = getActionBar();
        actionBar.setSubtitle(subTitle);
    } **/

    // The Handler that gets information back from the BluetoothChatService
    private final Handler mHandler = new Handler() {
        @Override
        public void handleMessage(final Message msg) {
            switch (msg.what) {
            case MESSAGE_STATE_CHANGE:
                if(D) Log.i(TAG, "MESSAGE_STATE_CHANGE: " + msg.arg1);
                switch (msg.arg1) {
                case BluetoothChatService.STATE_CONNECTED:
                    //setStatus(getString(R.string.title_connected_to, mConnectedDeviceName));
                    mConversationArrayAdapter.clear();
                    break;
                case BluetoothChatService.STATE_CONNECTING:
                   // setStatus(R.string.title_connecting);
                    break;
                case BluetoothChatService.STATE_LISTEN:
                case BluetoothChatService.STATE_NONE:
                    //setStatus(R.string.title_not_connected);
                    break;
                }
                break;
            case MESSAGE_WRITE:
                byte[] writeBuf = (byte[]) msg.obj;
                // construct a string from the buffer
                String writeMessage = new String(writeBuf);
                mConversationArrayAdapter.add("Me:  " + writeMessage);
                break;
            case MESSAGE_READ:
            byte[] readBuf = (byte[]) msg.obj;
                String readMessage = new String(readBuf,0,msg.arg1);
                transfer = readMessage;
                mConversationArrayAdapter.add("Voltage: "+ transfer);
                Complete();
                break;


            case MESSAGE_DEVICE_NAME:
                // save the connected device's name
                mConnectedDeviceName = msg.getData().getString(DEVICE_NAME);
                Toast.makeText(getApplicationContext(), "Connected to "
                               + mConnectedDeviceName, Toast.LENGTH_SHORT).show();
                break;
            case MESSAGE_TOAST:
                Toast.makeText(getApplicationContext(), msg.getData().getString(TOAST),
                               Toast.LENGTH_SHORT).show();
                break;
            }
        }
    };

    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        if(D) Log.d(TAG, "onActivityResult " + resultCode);
        switch (requestCode) {
        case REQUEST_CONNECT_DEVICE_SECURE:
            // When DeviceListActivity returns with a device to connect
            if (resultCode == Activity.RESULT_OK) {
                connectDevice(data, true);
            }
            break;
        case REQUEST_CONNECT_DEVICE_INSECURE:
            // When DeviceListActivity returns with a device to connect
            if (resultCode == Activity.RESULT_OK) {
                connectDevice(data, false);
            }
            break;
        case REQUEST_ENABLE_BT:
            // When the request to enable Bluetooth returns
            if (resultCode == Activity.RESULT_OK) {
                // Bluetooth is now enabled, so set up a chat session
                setupChat();
            } else {
                // User did not enable Bluetooth or an error occurred
                Log.d(TAG, "BT not enabled");
                Toast.makeText(this, R.string.bt_not_enabled_leaving, Toast.LENGTH_SHORT).show();
                finish();
            }
        }
    }

    private void connectDevice(Intent data, boolean secure) {
        // Get the device MAC address
        String address = data.getExtras()
            .getString(DeviceListActivity.EXTRA_DEVICE_ADDRESS);
        // Get the BluetoothDevice object
        BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
        // Attempt to connect to the device
        mChatService.connect(device, secure);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.option_menu, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        Intent serverIntent = null;
        switch (item.getItemId()) {
        case R.id.secure_connect_scan:
            // Launch the DeviceListActivity to see devices and do scan
            serverIntent = new Intent(this, DeviceListActivity.class);
            startActivityForResult(serverIntent, REQUEST_CONNECT_DEVICE_SECURE);
            return true;
        case R.id.insecure_connect_scan:
            // Launch the DeviceListActivity to see devices and do scan
            serverIntent = new Intent(this, DeviceListActivity.class);
            startActivityForResult(serverIntent, REQUEST_CONNECT_DEVICE_INSECURE);
            return true;
        case R.id.discoverable:
            // Ensure this device is discoverable by others
            ensureDiscoverable();
            return true;
        }
        return false;
    }


}

共 (2) 个答案

  1. # 2 楼答案

    RejectedExecutionException您的问题是由于队列的容量有限导致的,这会使任务一直等待(而不是线程池的大小)

    队列的默认容量为10

    如果要让更多任务排队,请使用executeOnExecutor而不是execute(在android>;3.0上)运行它们:

    // create fixed-size thread pool for Executor 
    private final ExecutorService mThreadPoolExecutor = 
        Executors.newFixedThreadPool(THREAD_POOL_SIZE);
    
    // then execute your task
    task.executeOnExecutor(mThreadPoolExecutor, bool);
    

    在这种情况下,队列容量将等于Integer.MAX_VALUE,而不是10,并且您不会拒绝任务(但是请注意不要在提交太多任务时耗尽内存)

    我还建议重命名Boolean bool变量,看起来非常混乱