Java 无法在ListView中设置图像

我正在尝试实现Pinterest样式的图像视图，如下所示：

我希望从SD卡中的特定文件夹设置图像。我正在尝试以下代码，但无法从文件夹中获取图像（显示一个空白的白色屏幕）

代码：

private void loadItems(){
String[] leftItems = new String[]{};
String[] rightItems = new String[]{};
ItemsAdapter mAdapter = null;
ArrayList<String> image_items = ItemsAdapter.getImages(); 
System.out.println("The images are obtained in image_items");
System.out.println("The list of images are" + image_items.toString());
mAdapter = new ItemsAdapter(this,R.layout.item,image_items);
listViewLeft.setAdapter(mAdapter);
listViewRight.setAdapter(mAdapter);
leftViewsHeights = new int[leftItems.length];
rightViewsHeights = new int[rightItems.length]; 
}

public class ItemsAdapter extends ArrayAdapter<String>{

    Context context; 
    LayoutInflater inflater;
    int layoutResourceId;
    float imageWidth;
    InputStream is;
    int item;
    public ItemsAdapter(Context context, int layoutResourceId, ArrayList<String> items) {
        super(context, layoutResourceId, items);
        this.context = context;
        this.layoutResourceId = layoutResourceId;
        float width = ((Activity)context).getWindowManager().getDefaultDisplay().getWidth();
        float margin = (int)convertDpToPixel(10f, (Activity)context);
        imageWidth = ((width - (3 * margin)) / 2);

    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        FrameLayout row = (FrameLayout) convertView;
        ItemHolder holder;
        String item = getItem(position);
        if (row == null) {
            holder = new ItemHolder();
            inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            row = (FrameLayout) inflater.inflate(layoutResourceId, parent, false);
            ImageView itemImage = (ImageView)row.findViewById(R.id.item_image);
            holder.itemImage = itemImage;
        } else {
            holder = (ItemHolder) row.getTag();
        }
        row.setTag(holder);
        setImageBit(item, holder.itemImage);
        return row;
    }

    public static class ItemHolder
    {
        ImageView itemImage;
    }

    // resize the image proportionately so it fits the entire space
    private void setImageBit(String path, ImageView imageView){
        path = android.os.Environment.getExternalStorageDirectory() + File.separator + "Pictures" + File.separator + "SanPics2";
        Bitmap bitmap = BitmapFactory.decodeFile(path);
        float i = ((float) imageWidth) / ((float) bitmap.getWidth());
        float imageHeight = i * (bitmap.getHeight());
        FrameLayout.LayoutParams params = (FrameLayout.LayoutParams) imageView.getLayoutParams();
        params.height = (int) imageHeight;
        params.width = (int) imageWidth;
        imageView.setLayoutParams(params);
        int count = 10;
        String file_name = null;
        for(int j = 1;j<count;j++)
        {
             file_name = "Image " + i + ".jpg";
        }
        //ArrayList<String> img_bitmap;
        //Bitmap bmp = ImgBitFromFile(path, file_name);
        imageView.setImageBitmap(bitmap);

    }

    public static float convertDpToPixel(float dp, Context context){
        Resources resources = context.getResources();
        DisplayMetrics metrics = resources.getDisplayMetrics();
        float px = dp * (metrics.densityDpi/160f);
        return px;
    }
    public static ArrayList<String> getImages()
    {
        String path = android.os.Environment.getExternalStorageDirectory() + File.separator +  "Pictures" + File.separator + "SanPics2";
        File mainfolder = new File(path);
        ArrayList<String> files = new ArrayList<String>();
        if(mainfolder.listFiles() == null)
        return null;
        for(File f : mainfolder.listFiles())
        {
            if(f.getName().contains(".jpg"))
            {
                files.add(f.getAbsolutePath());
            }
        }
        return files;
    }

ItemsActivity.java:

private void loadItems(){
String[] leftItems = new String[]{};
String[] rightItems = new String[]{};
ItemsAdapter mAdapter = null;
ArrayList<String> image_items = ItemsAdapter.getImages(); 
System.out.println("The images are obtained in image_items");
System.out.println("The list of images are" + image_items.toString());
mAdapter = new ItemsAdapter(this,R.layout.item,image_items);
listViewLeft.setAdapter(mAdapter);
listViewRight.setAdapter(mAdapter);
leftViewsHeights = new int[leftItems.length];
rightViewsHeights = new int[rightItems.length]; 
}

public class ItemsAdapter extends ArrayAdapter<String>{

    Context context; 
    LayoutInflater inflater;
    int layoutResourceId;
    float imageWidth;
    InputStream is;
    int item;
    public ItemsAdapter(Context context, int layoutResourceId, ArrayList<String> items) {
        super(context, layoutResourceId, items);
        this.context = context;
        this.layoutResourceId = layoutResourceId;
        float width = ((Activity)context).getWindowManager().getDefaultDisplay().getWidth();
        float margin = (int)convertDpToPixel(10f, (Activity)context);
        imageWidth = ((width - (3 * margin)) / 2);

    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        FrameLayout row = (FrameLayout) convertView;
        ItemHolder holder;
        String item = getItem(position);
        if (row == null) {
            holder = new ItemHolder();
            inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            row = (FrameLayout) inflater.inflate(layoutResourceId, parent, false);
            ImageView itemImage = (ImageView)row.findViewById(R.id.item_image);
            holder.itemImage = itemImage;
        } else {
            holder = (ItemHolder) row.getTag();
        }
        row.setTag(holder);
        setImageBit(item, holder.itemImage);
        return row;
    }

    public static class ItemHolder
    {
        ImageView itemImage;
    }

    // resize the image proportionately so it fits the entire space
    private void setImageBit(String path, ImageView imageView){
        path = android.os.Environment.getExternalStorageDirectory() + File.separator + "Pictures" + File.separator + "SanPics2";
        Bitmap bitmap = BitmapFactory.decodeFile(path);
        float i = ((float) imageWidth) / ((float) bitmap.getWidth());
        float imageHeight = i * (bitmap.getHeight());
        FrameLayout.LayoutParams params = (FrameLayout.LayoutParams) imageView.getLayoutParams();
        params.height = (int) imageHeight;
        params.width = (int) imageWidth;
        imageView.setLayoutParams(params);
        int count = 10;
        String file_name = null;
        for(int j = 1;j<count;j++)
        {
             file_name = "Image " + i + ".jpg";
        }
        //ArrayList<String> img_bitmap;
        //Bitmap bmp = ImgBitFromFile(path, file_name);
        imageView.setImageBitmap(bitmap);

    }

    public static float convertDpToPixel(float dp, Context context){
        Resources resources = context.getResources();
        DisplayMetrics metrics = resources.getDisplayMetrics();
        float px = dp * (metrics.densityDpi/160f);
        return px;
    }
    public static ArrayList<String> getImages()
    {
        String path = android.os.Environment.getExternalStorageDirectory() + File.separator +  "Pictures" + File.separator + "SanPics2";
        File mainfolder = new File(path);
        ArrayList<String> files = new ArrayList<String>();
        if(mainfolder.listFiles() == null)
        return null;
        for(File f : mainfolder.listFiles())
        {
            if(f.getName().contains(".jpg"))
            {
                files.add(f.getAbsolutePath());
            }
        }
        return files;
    }

private void loadItems（）{
字符串[]leftItems=新字符串[]{}；
String[]rightItems=新字符串[]{}；
ItemsAdapter mAdapter=null；
ArrayList image_items=ItemsAdapter.getImages（）；
System.out.println（“图像是在图像项中获得的”）；
System.out.println（“图像列表是”+image\u items.toString（））；
mAdapter=newitemsadapter（这个，R.layout.item，image\u items）；
setAdapter（mAdapter）；
setAdapter（mAdapter）；
leftViewsHeights=newint[leftItems.length]；
RightViewsHights=newint[rightItems.length]；
}

ItemsAdapter.java:

private void loadItems(){
String[] leftItems = new String[]{};
String[] rightItems = new String[]{};
ItemsAdapter mAdapter = null;
ArrayList<String> image_items = ItemsAdapter.getImages(); 
System.out.println("The images are obtained in image_items");
System.out.println("The list of images are" + image_items.toString());
mAdapter = new ItemsAdapter(this,R.layout.item,image_items);
listViewLeft.setAdapter(mAdapter);
listViewRight.setAdapter(mAdapter);
leftViewsHeights = new int[leftItems.length];
rightViewsHeights = new int[rightItems.length]; 
}

public class ItemsAdapter extends ArrayAdapter<String>{

    Context context; 
    LayoutInflater inflater;
    int layoutResourceId;
    float imageWidth;
    InputStream is;
    int item;
    public ItemsAdapter(Context context, int layoutResourceId, ArrayList<String> items) {
        super(context, layoutResourceId, items);
        this.context = context;
        this.layoutResourceId = layoutResourceId;
        float width = ((Activity)context).getWindowManager().getDefaultDisplay().getWidth();
        float margin = (int)convertDpToPixel(10f, (Activity)context);
        imageWidth = ((width - (3 * margin)) / 2);

    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        FrameLayout row = (FrameLayout) convertView;
        ItemHolder holder;
        String item = getItem(position);
        if (row == null) {
            holder = new ItemHolder();
            inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            row = (FrameLayout) inflater.inflate(layoutResourceId, parent, false);
            ImageView itemImage = (ImageView)row.findViewById(R.id.item_image);
            holder.itemImage = itemImage;
        } else {
            holder = (ItemHolder) row.getTag();
        }
        row.setTag(holder);
        setImageBit(item, holder.itemImage);
        return row;
    }

    public static class ItemHolder
    {
        ImageView itemImage;
    }

    // resize the image proportionately so it fits the entire space
    private void setImageBit(String path, ImageView imageView){
        path = android.os.Environment.getExternalStorageDirectory() + File.separator + "Pictures" + File.separator + "SanPics2";
        Bitmap bitmap = BitmapFactory.decodeFile(path);
        float i = ((float) imageWidth) / ((float) bitmap.getWidth());
        float imageHeight = i * (bitmap.getHeight());
        FrameLayout.LayoutParams params = (FrameLayout.LayoutParams) imageView.getLayoutParams();
        params.height = (int) imageHeight;
        params.width = (int) imageWidth;
        imageView.setLayoutParams(params);
        int count = 10;
        String file_name = null;
        for(int j = 1;j<count;j++)
        {
             file_name = "Image " + i + ".jpg";
        }
        //ArrayList<String> img_bitmap;
        //Bitmap bmp = ImgBitFromFile(path, file_name);
        imageView.setImageBitmap(bitmap);

    }

    public static float convertDpToPixel(float dp, Context context){
        Resources resources = context.getResources();
        DisplayMetrics metrics = resources.getDisplayMetrics();
        float px = dp * (metrics.densityDpi/160f);
        return px;
    }
    public static ArrayList<String> getImages()
    {
        String path = android.os.Environment.getExternalStorageDirectory() + File.separator +  "Pictures" + File.separator + "SanPics2";
        File mainfolder = new File(path);
        ArrayList<String> files = new ArrayList<String>();
        if(mainfolder.listFiles() == null)
        return null;
        for(File f : mainfolder.listFiles())
        {
            if(f.getName().contains(".jpg"))
            {
                files.add(f.getAbsolutePath());
            }
        }
        return files;
    }

公共类ItemsAdapter扩展了ArrayAdapter{
语境；
充气机；
国际布局资源；
浮动图像宽度；
输入流为；
国际项目；
公共项适配器（上下文上下文、内部布局资源ID、数组列表项）{
超级（上下文、布局资源ID、项目）；
this.context=上下文；
this.layoutResourceId=layoutResourceId；
浮动宽度=（（活动）上下文）.getWindowManager（）.getDefaultDisplay（）.getWidth（）；
浮动边距=（int）convertDpToPixel（10f，（活动）上下文）；
图像宽度=（（宽度-（3*边距））/2）；
}
@凌驾
公共视图getView（int位置、视图转换视图、视图组父视图）{
FrameLayout行=（FrameLayout）convertView；
物品持有人；
String item=getItem（位置）；
if（行==null）{
holder=新的ItemHolder（）；
充气器=（LayoutFlater）context.getSystemService（context.LAYOUT\u充气器\u服务）；
行=（框架布局）充气器。充气（布局资源ID，父项，false）；
ImageView itemImage=（ImageView）row.findViewById（R.id.item\u image）；
holder.itemImage=itemImage；
}否则{
holder=（ItemHolder）row.getTag（）；
}
row.setTag（支架）；
setImageBit（项目、持有者、项目图像）；
返回行；
}
公共静态类ItemHolder
{
图像查看项目图像；
}
//按比例调整图像大小，使其适合整个空间
私有void setImageBit（字符串路径，ImageView）{
path=android.os.Environment.getExternalStorageDirectory（）+File.separator+“Pictures”+File.separator+“SanPics2”；
位图位图=BitmapFactory.decodeFile（路径）；
float i=（（float）imageWidth）/（（float）bitmap.getWidth（））；
float imageHeight=i*（bitmap.getHeight（））；
FrameLayout.LayoutParams params=（FrameLayout.LayoutParams）imageView.getLayoutParams（）；
params.height=（int）图像高度；
params.width=（int）imageWidth；
imageView.setLayoutParams（参数）；
整数计数=10；
字符串文件_name=null；
对于（int j=1；j查看与您需要的相同且易于实现的样式。
这看起来像是gridview而不是ListView对于这种Pinterest样式，您必须使用gridview而不是ListView。但是，我已经使用drawables文件夹中图像的列表视图实现了上述样式。我将尝试并让您知道。谢谢。我相信这是需要的ires有两个支持库，而不是默认的支持库。我正在使用Eclipse，它会引发某些错误。我在哪里可以找到这些库？您是否已将其库项目添加到您的项目中？@San 3您提供的链接表示StaggedGridView的库，还有另一个名为StaggedGridViewDemo的文件，它表示一个简单的示例。我已将StaggedGridView库添加到演示项目中。但这似乎无法解决错误。错误是某些未知的类文件，因此我相信我必须导入某些其他库！！对吗？