如何在android gallery中设置nat目录路径

Question

我在互联网上找到了一个图像滑块的教程，但我不知道如何让它在手机上运行。在模拟器中它给我一个关于设置nat目录路径的消息。我不知道该怎么做。 。

有人可以帮助我吗？

活动代码是：

FullScreenViewActivity.java的代码：

public class FullScreenViewActivity extends Activity{

private Utils utils;
private FullScreenImageAdapter adapter;
private ViewPager viewPager;

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

    viewPager = (ViewPager) findViewById(R.id.pager);

    utils = new Utils(getApplicationContext());

    Intent i = getIntent();
    int position = i.getIntExtra("position", 0);

    adapter = new FullScreenImageAdapter(FullScreenViewActivity.this,
            utils.getFilePaths());

    viewPager.setAdapter(adapter);

    // displaying selected image first
    viewPager.setCurrentItem(position);
}
}

GridViewActivity.java的代码：

public class GridViewActivity extends Activity {

private Utils utils;
private ArrayList<String> imagePaths = new ArrayList<String>();
private GridViewImageAdapter adapter;
private GridView gridView;
private int columnWidth;

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

    gridView = (GridView) findViewById(R.id.grid_view);

    utils = new Utils(this);

    // Initilizing Grid View
    InitilizeGridLayout();

    // loading all image paths from SD card
    imagePaths = utils.getFilePaths();

    // Gridview adapter
    adapter = new GridViewImageAdapter(GridViewActivity.this, imagePaths,
            columnWidth);

    // setting grid view adapter
    gridView.setAdapter(adapter);
}

private void InitilizeGridLayout() {
    Resources r = getResources();
    float padding = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
            AppConstant.GRID_PADDING, r.getDisplayMetrics());

    columnWidth = (int) ((utils.getScreenWidth() - ((AppConstant.NUM_OF_COLUMNS + 1) * padding)) / AppConstant.NUM_OF_COLUMNS);

    gridView.setNumColumns(AppConstant.NUM_OF_COLUMNS);
    gridView.setColumnWidth(columnWidth);
    gridView.setStretchMode(GridView.NO_STRETCH);
    gridView.setPadding((int) padding, (int) padding, (int) padding,
            (int) padding);
    gridView.setHorizontalSpacing((int) padding);
    gridView.setVerticalSpacing((int) padding);
}

}

FullScreenImageAdapter.java的代码：

public class FullScreenImageAdapter extends PagerAdapter {

private Activity _activity;
private ArrayList<String> _imagePaths;
private LayoutInflater inflater;

// constructor
public FullScreenImageAdapter(Activity activity,
        ArrayList<String> imagePaths) {
    this._activity = activity;
    this._imagePaths = imagePaths;
}

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

@Override
public boolean isViewFromObject(View view, Object object) {
    return view == ((RelativeLayout) object);
}

@Override
public Object instantiateItem(ViewGroup container, int position) {
    TouchImageView imgDisplay;
    Button btnClose;

    inflater = (LayoutInflater) _activity
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View viewLayout = inflater.inflate(R.layout.layout_fullscreen_image, container,
            false);

    imgDisplay = (TouchImageView) viewLayout.findViewById(R.id.imgDisplay);
    btnClose = (Button) viewLayout.findViewById(R.id.btnClose);

    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inPreferredConfig = Bitmap.Config.ARGB_8888;
    Bitmap bitmap = BitmapFactory.decodeFile(_imagePaths.get(position), options);
    imgDisplay.setImageBitmap(bitmap);

    // close button click event
    btnClose.setOnClickListener(new View.OnClickListener() {            
        @Override
        public void onClick(View v) {
            _activity.finish();
        }
    }); 

    ((ViewPager) container).addView(viewLayout);

    return viewLayout;
}

@Override
public void destroyItem(ViewGroup container, int position, Object object) {
    ((ViewPager) container).removeView((RelativeLayout) object);

}

}

public class GridViewImageAdapter extends BaseAdapter {

private Activity _activity;
private ArrayList<String> _filePaths = new ArrayList<String>();
private int imageWidth;

public GridViewImageAdapter(Activity activity, ArrayList<String> filePaths,
        int imageWidth) {
    this._activity = activity;
    this._filePaths = filePaths;
    this.imageWidth = imageWidth;
}

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

@Override
public Object getItem(int position) {
    return this._filePaths.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    ImageView imageView;
    if (convertView == null) {
        imageView = new ImageView(_activity);
    } else {
        imageView = (ImageView) convertView;
    }

    // get screen dimensions
    Bitmap image = decodeFile(_filePaths.get(position), imageWidth,
            imageWidth);

    imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
    imageView.setLayoutParams(new GridView.LayoutParams(imageWidth,
            imageWidth));
    imageView.setImageBitmap(image);

    // image view click listener
    imageView.setOnClickListener(new OnImageClickListener(position));

    return imageView;
}

class OnImageClickListener implements OnClickListener {

    int _postion;

    // constructor
    public OnImageClickListener(int position) {
        this._postion = position;
    }

    @Override
    public void onClick(View v) {
        // on selecting grid view image
        // launch full screen activity
        Intent i = new Intent(_activity, FullScreenViewActivity.class);
        i.putExtra("position", _postion);
        _activity.startActivity(i);
    }

}

/*
 * Resizing image size
 */
public static Bitmap decodeFile(String filePath, int WIDTH, int HIGHT) {
    try {

        File f = new File(filePath);

        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(new FileInputStream(f), null, o);

        final int REQUIRED_WIDTH = WIDTH;
        final int REQUIRED_HIGHT = HIGHT;
        int scale = 1;
        while (o.outWidth / scale / 2 >= REQUIRED_WIDTH
                && o.outHeight / scale / 2 >= REQUIRED_HIGHT)
            scale *= 2;

        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
    return null;
}

}

GridViewImageAdapter.java的代码：

public class GridViewImageAdapter extends BaseAdapter {

private Activity _activity;
private ArrayList<String> _filePaths = new ArrayList<String>();
private int imageWidth;

public GridViewImageAdapter(Activity activity, ArrayList<String> filePaths,
        int imageWidth) {
    this._activity = activity;
    this._filePaths = filePaths;
    this.imageWidth = imageWidth;
}

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

@Override
public Object getItem(int position) {
    return this._filePaths.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    ImageView imageView;
    if (convertView == null) {
        imageView = new ImageView(_activity);
    } else {
        imageView = (ImageView) convertView;
    }

    // get screen dimensions
    Bitmap image = decodeFile(_filePaths.get(position), imageWidth,
            imageWidth);

    imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
    imageView.setLayoutParams(new GridView.LayoutParams(imageWidth,
            imageWidth));
    imageView.setImageBitmap(image);

    // image view click listener
    imageView.setOnClickListener(new OnImageClickListener(position));

    return imageView;
}

class OnImageClickListener implements OnClickListener {

    int _postion;

    // constructor
    public OnImageClickListener(int position) {
        this._postion = position;
    }

    @Override
    public void onClick(View v) {
        // on selecting grid view image
        // launch full screen activity
        Intent i = new Intent(_activity, FullScreenViewActivity.class);
        i.putExtra("position", _postion);
        _activity.startActivity(i);
    }

}

/*
 * Resizing image size
 */
public static Bitmap decodeFile(String filePath, int WIDTH, int HIGHT) {
    try {

        File f = new File(filePath);

        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(new FileInputStream(f), null, o);

        final int REQUIRED_WIDTH = WIDTH;
        final int REQUIRED_HIGHT = HIGHT;
        int scale = 1;
        while (o.outWidth / scale / 2 >= REQUIRED_WIDTH
                && o.outHeight / scale / 2 >= REQUIRED_HIGHT)
            scale *= 2;

        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
    return null;
}

}

util.java

public class Utils {

private Context _context;

// constructor
public Utils(Context context) {
    this._context = context;
}

/*
 * Reading file paths from SDCard
 */
public ArrayList<String> getFilePaths() {
    ArrayList<String> filePaths = new ArrayList<String>();

    File directory = new File(
            android.os.Environment.getExternalStorageDirectory()
                    + File.separator + AppConstant.PHOTO_ALBUM);

    // check for directory
    if (directory.isDirectory()) {
        // getting list of file paths
        File[] listFiles = directory.listFiles();

        // Check for count
        if (listFiles.length > 0) {

            // loop through all files
            for (int i = 0; i < listFiles.length; i++) {

                // get file path
                String filePath = listFiles[i].getAbsolutePath();

                // check for supported file extension
                if (IsSupportedFile(filePath)) {
                    // Add image path to array list
                    filePaths.add(filePath);
                }
            }
        } else {
            // image directory is empty
            Toast.makeText(
                    _context,
                    AppConstant.PHOTO_ALBUM
                            + " is empty. Please load some images in it !",
                    Toast.LENGTH_LONG).show();
        }

    } else {
        AlertDialog.Builder alert = new AlertDialog.Builder(_context);
        alert.setTitle("Error!");
        alert.setMessage(AppConstant.PHOTO_ALBUM
                + " directory path is not valid! Please set the image directory name AppConstant.java class");
        alert.setPositiveButton("OK", null);
        alert.show();
    }

    return filePaths;
}

/*
 * Check supported file extensions
 * 
 * @returns boolean
 */
private boolean IsSupportedFile(String filePath) {
    String ext = filePath.substring((filePath.lastIndexOf(".") + 1),
            filePath.length());

    if (AppConstant.FILE_EXTN
            .contains(ext.toLowerCase(Locale.getDefault())))
        return true;
    else
        return false;

}

/*
 * getting screen width
 */
public int getScreenWidth() {
    int columnWidth;
    WindowManager wm = (WindowManager) _context
            .getSystemService(Context.WINDOW_SERVICE);
    Display display = wm.getDefaultDisplay();

    final Point point = new Point();
    try {
        display.getSize(point);
    } catch (java.lang.NoSuchMethodError ignore) { // Older device
        point.x = display.getWidth();
        point.y = display.getHeight();
    }
    columnWidth = point.x;
    return columnWidth;
}
}

AppConstant.java

public class AppConstant {

// Number of columns of Grid View
public static final int NUM_OF_COLUMNS = 3;

// Gridview image padding
public static final int GRID_PADDING = 8; // in dp

// SD card image directory
public static final String PHOTO_ALBUM = "NAT";

// supported file formats
public static final List<String> FILE_EXTN = Arrays.asList("jpg", "jpeg",
        "png");
}

唯一的问题是设置nat目录路径，以便它可以在我的手机上运行。

Answer 1

我有同样的问题（同一个教程：D），问题是你需要一个地方存储所有壁纸，所以只需更改

// SD card image directory
 public static final String PHOTO_ALBUM = "NAT";

到

// SD card image directory
public static final String PHOTO_ALBUM = "Camera";

例如显示相机照片。

Answer 2

public static final String PHOTO_ALBUM =Environment.getExternalStorageDirectory().getPath()+ "/DCIM/"+"/100ANDRO/";

“/ DCIM / 100ANDRO /”是我的图片存储的路径。

Answer 3

在此处通过 DCIM /相机更改 NAT 您的内部手机内存照片。我尝试了这个和它的工作，但发生了一些其他问题，当我点击任何图片然后应用程序是强制停止，如果你解决这个问题然后让我知道。谢谢