AsyncTask应用仍然运行缓慢

Question

我有一个对位图产生影响的应用。当用户滑动滑动条时，效果的失真水平增加/减少，然后重绘位图。我的自定义视图类称为TouchView，此类获取位图并从处理图像的Filters类调用方法。我帮助实现了asyncTask以加快处理速度，但无济于事。是否正确实现了AsyncTask。谢谢马特。

public class TouchView extends View{


    private File tempFile;
    private byte[] imageArray;
    private Bitmap bgr;
    private Bitmap bm;
    private Bitmap bgr2 = null;;
    private Paint pTouch;
    private int centreX = 1;
    private int centreY = 1;
    private int radius = 50;
    private int Progress = 1;
    private static final String TAG = "*********TouchView";
    private Filters f = null;
    private boolean AsyncRunning = false;



    public TouchView(Context context) {
        super(context);
       // TouchView(context, null);
    }




    public TouchView(Context context, AttributeSet attr) {
        super(context,attr);



     //.....code that gets the bitmap from camera and sdcard

        bm = BitmapFactory.decodeByteArray(imageArray, 0, imageArray.length, bfo);
        bgr = Bitmap.createBitmap(bm.getWidth(), bm.getHeight(), bm.getConfig());
        bgr = bm.copy(bm.getConfig(), true);
        bgr2 = Bitmap.createBitmap(bm.getWidth(), bm.getHeight(), bm.getConfig());


      // instantiate the image processing class
      f = new Filters();





    }// end of touchView constructor


    public void findCirclePixels(){ 



        //set level of distortion
        float prog = (float)Progress/150000;

        // call processing method on bitmap
        bgr2 = f.barrel(bgr,prog);


        }// end of changePixel()





    }//end of onTouchEvent





    public void initSlider(final HorizontalSlider slider)
    {
        Log.e(TAG, "******setting up slider*********** ");
        slider.setOnProgressChangeListener(changeListener);
    }



    private OnProgressChangeListener changeListener = new OnProgressChangeListener() {


        @Override
        public void onProgressChanged(View v, int progress) {
            // TODO Auto-generated method stub

            setProgress(progress);

            Log.e(TAG, "***********progress = "+Progress);

        }
    };

    private class MyTask extends AsyncTask<Void, Void, Void> {
          protected void onPreExecute() {

            }

            @Override
            protected Void doInBackground(Void... params) {
              TouchView.this.findCirclePixels();
              return null;

            }

            protected void onPostExecute(Void result) {                               
              TouchView.this.invalidate();
            }
        }




    @Override
    public void onDraw(Canvas canvas){
        super.onDraw(canvas);


        canvas.drawBitmap(bgr2, 0, 0, null);




    }//end of onDraw




    protected void setProgress(int progress2) {
        this.Progress = progress2;
        new MyTask().execute();


    }




}

[更新] 这就是我现在所拥有的。不幸的是，该应用程序运行速度较慢。你有什么进一步的想法吗？

public class TouchView extends View{


    private File tempFile;
    private byte[] imageArray;
    private Bitmap bgr;
    private Bitmap bm;
    private Bitmap bgr2 = null;;
    private Paint pTouch;
    private int centreX = 1;
    private int centreY = 1;
    private int radius = 50;
    private int Progress = 1;
    private static final String TAG = "*********TouchView";
    private Filters f = null;
    private boolean AsyncRunning = false;
    private MyTask mt = null;



    public TouchView(Context context) {
        super(context);
       // TouchView(context, null);
    }




    public TouchView(Context context, AttributeSet attr) {
        super(context,attr);




        tempFile = new File(Environment.getExternalStorageDirectory().
                getAbsolutePath() + "/"+"image.jpg");

        imageArray = new byte[(int)tempFile.length()];


     try{

            InputStream is = new FileInputStream(tempFile);
            BufferedInputStream bis = new BufferedInputStream(is);
            DataInputStream dis = new DataInputStream(bis);


            int i = 0;

            while (dis.available() > 0) {
            imageArray[i] = dis.readByte();
            i++;
            }

            dis.close();

       } catch (Exception e) {

               e.printStackTrace();
            }



        BitmapFactory.Options bfo = new BitmapFactory.Options();
        bfo.inSampleSize = 1;

        bm = BitmapFactory.decodeByteArray(imageArray, 0, imageArray.length, bfo);
        bgr = Bitmap.createBitmap(bm.getWidth(), bm.getHeight(), bm.getConfig());
        bgr = bm.copy(bm.getConfig(), true);
        bgr2 = Bitmap.createBitmap(bm.getWidth(), bm.getHeight(), bm.getConfig());



      f = new Filters();




    }// end of touchView constructor


    public void findCirclePixels(){ 




        float prog = (float)Progress/150000;
        bgr2 = f.barrel(bgr,prog);


        }// end of changePixel()









    public void initSlider(final HorizontalSlider slider)
    {
        Log.e(TAG, "******setting up slider*********** ");
        slider.setOnProgressChangeListener(changeListener);
    }



    private OnProgressChangeListener changeListener = new OnProgressChangeListener() {


        @Override
        public void onProgressChanged(View v, int progress) {
            // TODO Auto-generated method stub

            setProgress(progress);

            Log.e(TAG, "***********progress = "+Progress);

        }
    };

    private class MyTask extends AsyncTask<Void, Void, Void> {
          protected void onPreExecute() {

            }

            @Override
            protected Void doInBackground(Void... params) {
              TouchView.this.findCirclePixels();

              return null;

            }

            protected void onPostExecute(Void result) { 

                while(!isCancelled()){
              TouchView.this.invalidate();
                }
                     mt.cancel(true);
            }
        }




    @Override
    public void onDraw(Canvas canvas){
        super.onDraw(canvas);


        canvas.drawBitmap(bgr2, 0, 0, null);
        canvas.drawCircle(centreX, centreY, radius,pTouch);



    }//end of onDraw




    protected void setProgress(int progress2) {
        this.Progress = progress2;


        mt = new MyTask();
        mt.execute();
        AsyncRunning = true;


    }




}

[更新2]

import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.ProgressBar;

public class HorizontalSlider extends ProgressBar {



    private OnProgressChangeListener listener;

    private static int padding = 2;

    public interface OnProgressChangeListener {
        void onProgressChanged(View v, int progress);
    }

    /*
    public HorizontalSlider(Context context, AttributeSet attrs,

                            Map inflateParams, int defStyle) {

                    super(context, attrs, inflateParams, defStyle);

            }



            public HorizontalSlider(Context context, AttributeSet attrs,

                            Map inflateParams) {

                    super(context, attrs, inflateParams, android.R.attr.progressBarStyleHorizontal);
}*/
    public HorizontalSlider(Context context) {
        super(context);

    }
    public HorizontalSlider(Context context, AttributeSet attrs) {
        super(context, attrs);
        // TODO Auto-generated constructor stub
    }


    public void setOnProgressChangeListener(OnProgressChangeListener l) {
        listener = l;
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {

        int action = event.getAction();

        if (action == MotionEvent.ACTION_DOWN
                || action == MotionEvent.ACTION_MOVE) {
            float x_mouse = event.getX() - padding;
            float width = getWidth() - 2*padding;
            int progress = Math.round((float) getMax() * (x_mouse / width));

            if (progress < 0)
                progress = 0;

            this.setProgress(progress);

            if (listener != null)
                listener.onProgressChanged(this, progress);

        }

        return true;
    }
}

[更新3]

嗨，好吧我已经将我的代码更改为你的amendements并更改了几行，以便通过添加TouchView.this.invalidate（）等来更新视图。关于horizo​​ntalSlider我已将其设置为仅检查设置进度时的ACTION_UP。这样，用户可以移动滑动条，但只有在用户释放滑动条时视图才会失效。我有点希望在移动条形图时实时更新位图，但图像处理类“过滤器”需要大约20秒来处理一个不好的位图。我认为我需要处理后者，因为我确信你应该能够比这更快地处理位图！:)。如果这和AsyncTask一样快，那么我可能不得不考虑首先绘制相机位图而不失真，然后创建另一个只存在圆效应的位图叠加。这样滤波器编码只有1/3的像素可以循环通过？我会发布代码，以确保它是你的建议。

import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;

import com.tecmark.HorizontalSlider.OnProgressChangeListener;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuffXfermode;
import android.graphics.PorterDuff.Mode;
import android.os.AsyncTask;
import android.os.Environment;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;

public class TouchView extends View{


    private File tempFile;
    private byte[] imageArray;
    private Bitmap bgr;
    private Bitmap bm;
    private Bitmap bgr2 = null;;
    private Paint pTouch;
    private int centreX = 1;
    private int centreY = 1;
    private int radius = 50;
    private int Progress = 1;
    private static final String TAG = "*********TouchView";
    private Filters f = null;
    private boolean AsyncRunning = false;
    private MyTask mt = null;



    public TouchView(Context context) {
        super(context);
       // TouchView(context, null);
    }




    public TouchView(Context context, AttributeSet attr) {
        super(context,attr);




        tempFile = new File(Environment.getExternalStorageDirectory().
                getAbsolutePath() + "/"+"image.jpg");

        imageArray = new byte[(int)tempFile.length()];


     try{

            InputStream is = new FileInputStream(tempFile);
            BufferedInputStream bis = new BufferedInputStream(is);
            DataInputStream dis = new DataInputStream(bis);


            int i = 0;

            while (dis.available() > 0) {
            imageArray[i] = dis.readByte();
            i++;
            }

            dis.close();

       } catch (Exception e) {

               e.printStackTrace();
            }



        BitmapFactory.Options bfo = new BitmapFactory.Options();
        bfo.inSampleSize = 1;

        bm = BitmapFactory.decodeByteArray(imageArray, 0, imageArray.length, bfo);
        bgr = Bitmap.createBitmap(bm.getWidth(), bm.getHeight(), bm.getConfig());
        bgr = bm.copy(bm.getConfig(), true);
        bgr2 = Bitmap.createBitmap(bm.getWidth(), bm.getHeight(), bm.getConfig());



       f = new Filters();


        pTouch = new Paint(Paint.ANTI_ALIAS_FLAG);         
        pTouch.setXfermode(new PorterDuffXfermode(Mode.SRC_OUT)); 
        pTouch.setColor(Color.TRANSPARENT);
        pTouch.setStyle(Paint.Style.STROKE);


    }// end of touchView constructor


    public void findCirclePixels(){ 




        float prog = (float)Progress/150000;
        bgr2 = f.barrel(bgr,prog);


        }// end of changePixel()







    public void initSlider(final HorizontalSlider slider)
    {
      //  Log.e(TAG, "******setting up slider*********** ");
        slider.setOnProgressChangeListener(changeListener);
    }



    private OnProgressChangeListener changeListener = new OnProgressChangeListener() {


        @Override
        public void onProgressChanged(View v, int progress) {
            // TODO Auto-generated method stub

            setProgress(progress);

            //TouchView.this.Progress = progress;

              if (mt != null) {
                mt.cancel(true);
              }

              mt = new MyTask();
              mt.execute();


        }
    };

    private class MyTask extends AsyncTask<Void, Void, Void> {
          protected void onPreExecute() {
            //  Log.e(TAG, "***********in PREEXECUTE");
            }

            @Override
            protected Void doInBackground(Void... params) {
            //  Log.e(TAG, "***********in DOINBACKGROUND");
                if(!mt.isCancelled()){
            //  Log.e(TAG, "***********in doInBackgroud about to call fcp()");
            //  Log.e(TAG, "***********in doinbackground asyncStatus = "+mt.getStatus());
              TouchView.this.findCirclePixels();
              Log.e(TAG, "***********in doinbackground fcp() called!!!!");
                }

              return null;

            }

            protected void onPostExecute(Void result) { 
            //  Log.e(TAG, "***********in POSTEXECUTE");
                if(!isCancelled()){
           // Log.e(TAG, "***********in postExecute task not canclled and about to invalidate");
          //  Log.e(TAG, "***********in postexecute asyncStatus = "+mt.getStatus());
              TouchView.this.invalidate();
          //    Log.e(TAG, "***********in postexecute  invalidate() called!!!!");
           //   Log.e(TAG, "***********in postexecute asyncStatus = "+mt.getStatus());
                }


            }



        }// end of mytask




    @Override
    public void onDraw(Canvas canvas){
        super.onDraw(canvas);


        canvas.drawBitmap(bgr2, 0, 0, null);
        canvas.drawCircle(centreX, centreY, radius,pTouch);



    }//end of onDraw




    protected void setProgress(int progress2) {
        //Log.e(TAG, "***********in SETPROGRESS");
        this.Progress = progress2;

        //Log.e(TAG, "***********in setprogress progress = "+Progress);

        //Log.e(TAG, "***********in setProgress about to create mytask ");
        mt = new MyTask();
        //Log.e(TAG, "***********in setprogress about to execute mytask");
        //Log.e(TAG, "***********in setprogress asyncStatus = "+mt.getStatus());
        mt.execute();
    //  Log.e(TAG, "***********in setprogress asyncStatus = "+mt.getStatus());
    //  Log.e(TAG, "***********in setprogress mytask executed!!!!! ");



    }




}

@Override
    public boolean onTouchEvent(MotionEvent event) {

        int action = event.getAction();

        if (action == MotionEvent.ACTION_UP
                /*|| action == MotionEvent.ACTION_MOVE*/) {
            float x_mouse = event.getX() - padding;
            float width = getWidth() - 2*padding;

             int progress = Math.round((float) getMax() * (x_mouse / width));

            if (progress < 0)
                progress = 0;

            this.setProgress(progress);

            if (listener != null)
                listener.onProgressChanged(this, progress);
        }


        return true;
    }
}

Answer 1

对于滑块中的每个值更改，您似乎都在创建MyTask并运行它。相反，可能表现更好的一件事只是在滑块被释放（停止移动）时更新你的监听器。看起来HorizontalSlider是一个自定义类，所以我无法代表那里发生的事情。

如果滑块从左向右移动，则在移动过程中可能会触发100次更新事件。这将是100个后台任务！

<强>更新

在您制作另一个cancel()之前，MyTask有一种可能性。isCancelled()如果您采用该路线，则需要在onPostExecute中致电findCirclePixels()，并且只有在未取消任务时才会使您的观看无效。但是，如果MyTask中的代码是瓶颈，则无效。我的猜测是，在创建新任务之前取消活动任务将不解决您的问题。

正确编码（仅在必要时创建AsyncTask）仍然是最佳路线。考虑到每个doInBackground()操作系统必须生成一个新的后台线程，它有自己的开销。不要被public class TouchView extends View{ private File tempFile; private byte[] imageArray; private Bitmap bgr; private Bitmap bm; private Bitmap bgr2 = null;; private Paint pTouch; private int centreX = 1; private int centreY = 1; private int radius = 50; private int Progress = 1; private static final String TAG = "*********TouchView"; private Filters f = null; private MyTask mt = null; public TouchView(Context context) { super(context); } public TouchView(Context context, AttributeSet attr) { super(context,attr); tempFile = new File(Environment.getExternalStorageDirectory(). getAbsolutePath() + "/"+"image.jpg"); imageArray = new byte[(int) tempFile.length()]; try{ InputStream is = new FileInputStream(tempFile); BufferedInputStream bis = new BufferedInputStream(is); DataInputStream dis = new DataInputStream(bis); int i = 0; while (dis.available() > 0) { imageArray[i] = dis.readByte(); i++; } dis.close(); } catch (Exception e) { e.printStackTrace(); } BitmapFactory.Options bfo = new BitmapFactory.Options(); bfo.inSampleSize = 1; bm = BitmapFactory.decodeByteArray(imageArray, 0, imageArray.length, bfo); bgr = Bitmap.createBitmap(bm.getWidth(), bm.getHeight(), bm.getConfig()); bgr = bm.copy(bm.getConfig(), true); bgr2 = Bitmap.createBitmap(bm.getWidth(), bm.getHeight(), bm.getConfig()); f = new Filters(); } public void findCirclePixels(){ float prog = (float) Progress / 150000; bgr2 = f.barrel(bgr, prog); } public void initSlider(final HorizontalSlider slider) { slider.setOnProgressChangeListener(changeListener); } private OnProgressChangeListener changeListener = new OnProgressChangeListener() { @Override public void onProgressChanged(View v, int progress) { /* TODO: If there is a way to see if the slider is still being changed (control has not been released), then you should return and not continue with the creation of another task */ this.Progress = progress2; if (mt != null) { mt.cancel(); } mt = new MyTask(); mt.execute(); } }; private class MyTask extends AsyncTask<Void, Void, Void> { protected void onPreExecute() { } @Override protected Void doInBackground(Void... params) { // This check is not necessary if coded properly if (!isCancelled()) { TouchView.this.findCirclePixels(); } return null; } protected void onPostExecute(Void result) { // This check is not necessary if coded properly if (!isCancelled()) { TouchView.this.invalidate(); } } } @Override public void onDraw(Canvas canvas){ super.onDraw(canvas); canvas.drawBitmap(bgr2, 0, 0, null); canvas.drawCircle(centreX, centreY, radius, pTouch); } } 中放入的少量代码所迷惑。

再次更新

我已清理您的代码并添加了建议评论：

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