Gridview - 单击图像以在 Viewpager 中查看图像

Question

这是一个从 json 获取图像的网格视图。它工作正常。我想单击此网格视图中的图像以显示完整图像并可以滑动它。我发现这个问题的解决方案是使用 Viewpager。

如何在gridview中点击图片显示图片并可以滑动？

您可以更轻松地阅读此代码。 http://pastebin.com/Q8Ljt9yL

public class MainActivity extends Activity {

public static final int DIALOG_DOWNLOAD_JSON_PROGRESS = 0;
private ProgressDialog mProgressDialog;
ArrayList<HashMap<String, Object>> MyArrList;

@SuppressLint("NewApi")
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Permission StrictMode
    if (android.os.Build.VERSION.SDK_INT > 9) {
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy);
    }
    // Download JSON File
    new DownloadJSONFileAsync().execute();
} 

@Override
protected Dialog onCreateDialog(int id) {
    switch (id) {
    case DIALOG_DOWNLOAD_JSON_PROGRESS:
        mProgressDialog = new ProgressDialog(this);
        mProgressDialog.setMessage("Downloading.....");
        mProgressDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
        mProgressDialog.setCancelable(true);
        mProgressDialog.show();
        return mProgressDialog;
    default:
        return null;
    }
}

public void ShowAllContent() {
    final GridView gridView1 = (GridView) findViewById(R.id.gridView1);
    gridView1.setAdapter(new ImageAdapter(MainActivity.this, MyArrList));
    gridView1.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View v, int position, long id) {

            Toast.makeText(getApplicationContext(), "this is", Toast.LENGTH_SHORT).show();
        }
    });
}

public class ImageAdapter extends BaseAdapter {
    private Context context;
    private ArrayList<HashMap<String, Object>> MyArr = new ArrayList<HashMap<String, Object>>();

    public ImageAdapter(Context c, ArrayList<HashMap<String, Object>> myArrList) {
        context = c;
        MyArr = myArrList;
    }

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

    public Object getItem(int position) {
        return position;
    }

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

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder viewHolder;
        View myView = convertView;
        viewHolder = new ViewHolder();
        if (convertView == null) {
            LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            myView = inflater.inflate(R.layout.activity_column, null);

            viewHolder.imageView = (ImageView) myView.findViewById(R.id.ColImgPath);
            viewHolder.imageView.getLayoutParams().height = 120;
            viewHolder.imageView.getLayoutParams().width = 120;
            viewHolder.imageView.setPadding(5, 5, 5, 5);
            viewHolder.imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
            try {
                viewHolder.imageView.setImageBitmap((Bitmap) MyArr.get(position).get("ImageThumBitmap"));
            } catch (Exception e) {
                viewHolder.imageView.setImageResource(android.R.drawable.ic_menu_report_image);
            }
        }
        return myView;
    }
}

private static class ViewHolder {
    public ImageView imageView;
}

// Download JSON in Background
public class DownloadJSONFileAsync extends AsyncTask<String, Void, Void> {

    protected void onPreExecute() {
        super.onPreExecute();
        showDialog(DIALOG_DOWNLOAD_JSON_PROGRESS);
    }

    @Override
    protected Void doInBackground(String... params) {

        String url = "http://192.168.10.101/adchara1/";
        JSONArray data;
        try {
            data = new JSONArray(getJSONUrl(url));
            MyArrList = new ArrayList<HashMap<String, Object>>();
            HashMap<String, Object> map;

            for (int i = 0; i < data.length(); i++) {
                JSONObject c = data.getJSONObject(i);
                map = new HashMap<String, Object>();

                map.put("photo", (String) c.getString("photo"));
                map.put("ImageThumBitmap",(Bitmap) loadBitmap(c.getString("photo")));

                // Full (for View Popup)
                map.put("frame", (String) c.getString("frame"));

                MyArrList.add(map);
            }

        } catch (JSONException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return null;
    }

    protected void onPostExecute(Void unused) {
        ShowAllContent(); // When Finish Show Content
        dismissDialog(DIALOG_DOWNLOAD_JSON_PROGRESS);
        removeDialog(DIALOG_DOWNLOAD_JSON_PROGRESS);
    }
}

/*** Get JSON Code from URL ***/
public String getJSONUrl(String url) {
    StringBuilder str = new StringBuilder();
    HttpClient client = new DefaultHttpClient();
    HttpGet httpGet = new HttpGet(url);
    try {
        HttpResponse response = client.execute(httpGet);
        StatusLine statusLine = response.getStatusLine();
        int statusCode = statusLine.getStatusCode();
        if (statusCode == 200) { // Download OK
            HttpEntity entity = response.getEntity();
            InputStream content = entity.getContent();
            BufferedReader reader = new BufferedReader(new InputStreamReader(content));
            String line;
            while ((line = reader.readLine()) != null) {
                str.append(line);
            }
        } else {
            Log.e("Log", "Failed to download file..");
        }
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    return str.toString();
}

/***** Get Image Resource from URL (Start) *****/
private static final String TAG = "Image";
private static final int IO_BUFFER_SIZE = 4 * 1024;

public static Bitmap loadBitmap(String url) {
    Bitmap bitmap = null;
    InputStream in = null;
    BufferedOutputStream out = null;

    try {
        in = new BufferedInputStream(new URL(url).openStream(),IO_BUFFER_SIZE);

        final ByteArrayOutputStream dataStream = new ByteArrayOutputStream();
        out = new BufferedOutputStream(dataStream, IO_BUFFER_SIZE);
        copy(in, out);
        out.flush();

        final byte[] data = dataStream.toByteArray();
        BitmapFactory.Options options = new BitmapFactory.Options();
        // options.inSampleSize = 1;

        bitmap = BitmapFactory.decodeByteArray(data, 0, data.length,options);
    } catch (IOException e) {
        Log.e(TAG, "Could not load Bitmap from: " + url);
    } finally {
        closeStream(in);
        closeStream(out);
    }
    return bitmap;
}

private static void closeStream(Closeable stream) {
    if (stream != null) {
        try {
            stream.close();
        } catch (IOException e) {
            android.util.Log.e(TAG, "Could not close stream", e);
        }
    }
}

private static void copy(InputStream in, OutputStream out)
        throws IOException {
    byte[] b = new byte[IO_BUFFER_SIZE];
    int read;
    while ((read = in.read(b)) != -1) {
        out.write(b, 0, read);
    }
}
}

Answer 1

它和你需要的一样。只需单击网格视图的事件并使用视图寻呼机在下一个屏幕中获取图像。

网格视图图片的点击事件：

GridView gridView = (GridView) findViewById(R.id.gridview);
        gridView.setAdapter(new ImageAdapter());
        gridView.setOnItemClickListener(new OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) 
         {
          HashMap<String, Object> selected = (HashMap<String, Object>)  

          gridView.getItemAtPosition(position);

            }
        });

Answer 2

首先，您必须实现 ImageAdapter 类的方法 getItem(int position) 以返回 MyArr 中“位置”处的项目。 接下来，在点击监听器中，您可以执行类似的操作

HashMap<String, Object> selected = (HashMap<String, Object>) gridView.getItemAtPosition(position);

选中后，您就有了位图。

Answer 3

看到这个class你可以找到

GridView gridView = (GridView) findViewById(R.id.gridview);
        gridView.setAdapter(new ImageAdapter());
        gridView.setOnItemClickListener(new OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) {
                startImageGalleryActivity(position);
            }
        });

在这里你会得到你想要的相同的输出。

您也可以下载完整的源代码here

Answer 4

这是你图片的网址吗？

-> map.put("photo", (String) c.getString("photo"));//on your main activity

尝试在 myView 上使用 onclick

myView.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {
        HashMap<String, Object> result = new HashMap<String, Object>();
        result = MyArr.get(position);
        Intent intent = new Intent(context, youractivitytarget.class);
        intent.putExtra("photo", (String)result.get(MainActivity.PHOTO));
        context.startActivity(intent);
    }
});

然后使用 url 再次下载您点击的照片