Question

当点击GridView中的一个图片时，它需要显示图像的完整视图，我该如何实现？这是课程。

public class MainActivity extends Activity {

    ImageAdapter myImageAdapter;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    GridView gridview = (GridView) findViewById(R.id.gridview);
    myImageAdapter = new ImageAdapter(this);
    gridview.setAdapter(myImageAdapter);

    String ExternalStorageDirectoryPath = Environment
            .getExternalStorageDirectory()
            .getAbsolutePath();

    String targetPath = ExternalStorageDirectoryPath + "/test/";

    Toast.makeText(getApplicationContext(), targetPath, Toast.LENGTH_LONG).show();
    File targetDirector = new File(targetPath);
    File[] files = targetDirector.listFiles();
    for (File file : files){
        myImageAdapter.add(file.getAbsolutePath());

    } 

    //ADDED this one
    gridview.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View v,
                    int position, long id) {

                // Sending image id to FullScreenActivity
                Intent i = new Intent(getApplicationContext(), FullView.class);
                // passing array index
                i.putExtra("id", position);
                startActivity(i);
            }
        });
}

适配器类

public class ImageAdapter extends BaseAdapter {

    private Context mContext;
    ArrayList<String> itemList = new ArrayList<String>();

    public ImageAdapter(Context c) {
        mContext = c;   
    }

    void add(String path){
        itemList.add(path); 
    }

    public int getCount() {
        return itemList.size();
    }

    public Object getItem(int arg0) {
        // TODO Auto-generated method stub
        return null;
    }

    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return 0;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView imageView;
        if (convertView == null) {  // if it's not recycled, initialize some attributes
            imageView = new ImageView(mContext);
            imageView.setLayoutParams(new GridView.LayoutParams(220, 220));
            imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
            imageView.setPadding(8, 8, 8, 8);
        } else {
            imageView = (ImageView) convertView;
        }

        Bitmap bm = decodeSampledBitmapFromUri(itemList.get(position), 220, 220);

        imageView.setImageBitmap(bm);
        return imageView;
    }

    public Bitmap decodeSampledBitmapFromUri(String path, int reqWidth, int reqHeight) {

        Bitmap bm = null;
        // First decode with inJustDecodeBounds=true to check dimensions
        final BitmapFactory.Options options = new BitmapFactory.Options();
        options.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(path, options);

        // Calculate inSampleSize
        options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

        // Decode bitmap with inSampleSize set
        options.inJustDecodeBounds = false;
        bm = BitmapFactory.decodeFile(path, options); 

        return bm;      
    }

    public int calculateInSampleSize(

        BitmapFactory.Options options, int reqWidth, int reqHeight) {
        // Raw height and width of image
        final int height = options.outHeight;
        final int width = options.outWidth;
        int inSampleSize = 1;

        if (height > reqHeight || width > reqWidth) {
            if (width > height) {
                inSampleSize = Math.round((float)height / (float)reqHeight);    
            } else {
                inSampleSize = Math.round((float)width / (float)reqWidth);      
            }   
        }

        return inSampleSize;    
    }

}



}

这是我遇到问题的地方。我不知道如何在这里查看图片，这意味着我在GridView中点击了图像的完整视图。

public class FullView extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    // get intent data
    Intent i = getIntent();
    // Selected image id

    int position = i.getExtras().getInt("id");
    ImageAdapter imageAdapter = new ImageAdapter(this);

    ImageView imageView = new ImageView(this);

   //IM HAVING PROBLEMS WITH THIS LINE.
    imageView.setImageResource(imageAdapter.itemList.get(position));
}

}

Answer 1

如果你确定

imageAdapter.itemList.get(position)

为您提供图像，然后尝试将布局参数添加到imageview。

LayoutParams lp = new LayoutParams(LayoutParams.WRAP_CONTENT,
        LayoutParams.WRAP_CONTENT);
imageView.setLayoutParams(lp);

编辑： - 这应该有用。尝试将图像路径设置为意图

gridview.setOnItemClickListener(new OnItemClickListener() {
    public void onItemClick(AdapterView<?> parent, View v,
            int position, long id) {
        // Sending image id to FullScreenActivity
        Intent i = new Intent(getApplicationContext(), FullView.class);
        // passing array index
        i.putExtra("uri", myImageAdapter.itemList.get(position));
        startActivity(i);
    }
});

在第二个活动中使用

public class FullView extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // get intent data
        Intent i = getIntent();

        // Selected image id
        String uri = i.getStringExtra('uri');
        ImageView imageView = new ImageView(this);
        LayoutParams lp = new LayoutParams(LayoutParams.WRAP_CONTENT,
                LayoutParams.WRAP_CONTENT);
        imageView.setLayoutParams(lp);
        Uri imageUri = Uri.parse(imagePath);
        imageView.setImageUri(imageUri);
    }
}

Answer 2

您的itemList包含图片路径，但您正在尝试设置图片资源。你应该设置图像uri。

String imagePath = imageAdapter.itemList.get(position);
Uri imageUri = Uri.parse(imagePath);
imageView.setImageUri(imageUri);

或者从路径创建一个drawable：

Drawable d = Drawable.createFromPath(imagePath);
imageView.setImageDrawable(d);

修改

考虑到这一点，您将图像位置发送到第二个活动，但ImageAdapter将为空，因为它是另一个活动。

因此，您应该发送图像路径，而不是在意图中发送位置。

单击后，如何在Gridview中查看图片的完整图像

2 个答案: