如何使用片段在viewpager中打开sd卡的多个图像？

Question

I am new to android, I am making an app which can select and open multiple images from the gallery and can be viewed as slides. Then use paint canvas to draw on the images and record the whole screen.

I have managed to do all the parts except loading multiple images from the gallery into my app.

I can open images from drawable but finding difficulty to open from the gallery.

I am using ViewPager and fragment to open images from drawable, plz let me know a way to open multiple images from the gallery and show in my ViewPager .

page fragment class

package com.example.test2;

public class PageFragment extends Fragment {

    private int imageResource;
    private Bitmap bitmap;

    public static PageFragment getInstance(int resourceID) {
        PageFragment f = new PageFragment();
        Bundle args = new Bundle();
        args.putInt("image_source", resourceID);
        f.setArguments(args);
        return f;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        imageResource = getArguments().getInt("image_source");


    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_page, container, false);
    }

    @Override
    public void onViewCreated(View view, Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        ImageView imageView = (ImageView) view.findViewById(R.id.image);

        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inSampleSize = 4;
        o.inDither = false;
        bitmap = BitmapFactory.decodeResource(getResources(), imageResource, o);
        imageView.setImageBitmap(bitmap);
    }
    @Override
    public void onDestroy() {
        super.onDestroy();
        bitmap.recycle();
        bitmap = null;
    }
}

viewPagerAdapter class

package com.example.test2;

public class ViewPagerAdapter extends FragmentStatePagerAdapter {

    private List<Integer> images;

    public ViewPagerAdapter(FragmentManager fm, List<Integer> imagesList) {
        super(fm);
        this.images = imagesList;
    }

    @Override
    public Fragment getItem(int position) {
        return PageFragment.getInstance(images.get(position));
    }

    @Override
    public int getCount() {
        return images.size();
    }
}

MainActivity

package com.example.test2;

public class MainActivity extends AppCompatActivity {

    ImageButton draw;
    RelativeLayout relativeLayout;
    Paint paint;
    View view;
    Path path2;
    Bitmap bitmap;
    Canvas canvas;

    private ArrayList<Integer> images;
    private BitmapFactory.Options options;
    private ViewPager viewPager;
    private View btnNext, btnPrev;
    private FragmentStatePagerAdapter adapter;
    private LinearLayout thumbnailsContainer;


    private final static Integer[] resourceIDs = new Integer[]{R.mipmap.image7,R.mipmap.image6,R.mipmap.image5

    };

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

        images = new ArrayList<>();

        //find view by id
        viewPager = (ViewPager) findViewById(R.id.view_pager);
        thumbnailsContainer = (LinearLayout) findViewById(R.id.container);
        btnNext = findViewById(R.id.next);
        btnPrev = findViewById(R.id.prev);

        btnPrev.setOnClickListener(onClickListener(0));
        btnNext.setOnClickListener(onClickListener(1));

        setImagesData();

        // init viewpager adapter and attach
        adapter = new ViewPagerAdapter(getSupportFragmentManager(), images);
        viewPager.setAdapter(adapter);

        inflateThumbnails();

        relativeLayout = (RelativeLayout) findViewById(R.id.layout);
        draw= findViewById(R.id.b);
        draw.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                final Dialog dialog = new Dialog(MainActivity.this);
                dialog.setTitle("");
                dialog.setContentView(R.layout.menu);
                dialog.show();

                Button black = dialog.findViewById(R.id.Black);
                Button blue = dialog.findViewById(R.id.Blue);
                Button red = dialog.findViewById(R.id.Red);



                black.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        color();
                        paint.setColor(Color.parseColor("black"));
                        dialog.dismiss();
                    }
                });
                blue.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {

                        color();
                        paint.setColor(Color.parseColor("blue"));
                        dialog.dismiss();

                    }
                });

                red.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        color();
                        paint.setColor(Color.parseColor("red"));
                        dialog.dismiss();

                    }
                });

            }
        });


    }




    private View.OnClickListener onClickListener(final int i) {
        return new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (i > 0) {
                    //next page
                    if (viewPager.getCurrentItem() < viewPager.getAdapter().getCount() - 1) {
                        viewPager.setCurrentItem(viewPager.getCurrentItem() + 1);
                    }
                } else {
                    //previous page
                    if (viewPager.getCurrentItem() > 0) {
                        viewPager.setCurrentItem(viewPager.getCurrentItem() - 1);
                    }
                }
            }
        };
    }

    private void setImagesData() {
        for (int i = 0; i < resourceIDs.length; i++) {
            images.add(resourceIDs[i]);
        }
    }

    private void inflateThumbnails() {
        for (int i = 0; i < images.size(); i++) {
            View imageLayout = getLayoutInflater().inflate(R.layout.item_image, null);
            ImageView imageView = (ImageView) imageLayout.findViewById(R.id.img_thumb);
            imageView.setOnClickListener(onChagePageClickListener(i));
            options = new BitmapFactory.Options();
            options.inSampleSize = 3;
            options.inDither = false;
            Bitmap bitmap = BitmapFactory.decodeResource(getResources(),images.get(i),options);
            imageView.setImageBitmap(bitmap);
            //set to image view
            imageView.setImageBitmap(bitmap);
            //add imageview
            thumbnailsContainer.addView(imageLayout);
        }
    }

    private View.OnClickListener onChagePageClickListener(final int i) {
        return new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                viewPager.setCurrentItem(i);
            }
        };
    }

    public void color()
    {
        view = new SketchSheetView(MainActivity.this);
        paint = new Paint();
        path2 = new Path();
        relativeLayout.addView(view, new ViewGroup.LayoutParams(
                RelativeLayout.LayoutParams.MATCH_PARENT,
                RelativeLayout.LayoutParams.MATCH_PARENT));
        paint.setDither(true);
        paint.setStyle(Paint.Style.STROKE);
        paint.setStrokeJoin(Paint.Join.ROUND);
        paint.setStrokeCap(Paint.Cap.ROUND);
        paint.setStrokeWidth(6);

    }
    class SketchSheetView extends View {
        public SketchSheetView(Context context) {
            super(context);
            bitmap = Bitmap.createBitmap(820, 480, Bitmap.Config.ARGB_4444);
            canvas = new Canvas(bitmap);
            this.setBackgroundColor(Color.TRANSPARENT);
        }

        private ArrayList<DrawingClass> DrawingClassArrayList = new ArrayList<DrawingClass>();

        @Override
        public boolean onTouchEvent(MotionEvent event) {

            DrawingClass pathWithPaint = new DrawingClass();
            canvas.drawPath(path2, paint);
            if (event.getAction() == MotionEvent.ACTION_DOWN) {
                path2.moveTo(event.getX(), event.getY());
                path2.lineTo(event.getX(), event.getY());
            }
            else if (event.getAction() == MotionEvent.ACTION_MOVE) {
                path2.lineTo(event.getX(), event.getY());
                pathWithPaint.setPath(path2);
                pathWithPaint.setPaint(paint);
                DrawingClassArrayList.add(pathWithPaint);
            }
            invalidate();
            return true;
        }
        @Override
        protected void onDraw(Canvas canvas) {
            super.onDraw(canvas);
            if (DrawingClassArrayList.size() > 0) {
                canvas.drawPath(
                        DrawingClassArrayList.get(DrawingClassArrayList.size() - 1).getPath(),
                        DrawingClassArrayList.get(DrawingClassArrayList.size() - 1).getPaint());
            }
        }
    }

    public class DrawingClass {
        Path DrawingClassPath;
        Paint DrawingClassPaint;
        private Path getPath() {
            return DrawingClassPath;
        }
        private void setPath(Path path) {
            this.DrawingClassPath = path;
        }
        private Paint getPaint() {
            return DrawingClassPaint;
        }
        private void setPaint(Paint paint) {
            this.DrawingClassPaint = paint;
        }
    }

}

Answer 1

I'm not sure it's possible directly since to reach the gallery, you need to call an intent.

I suggest you to launch a method to retrieve photos in the gallery, following this example: enter link description here , to save all images into a list, and to display pictures in viewpager like you've aldready done.