java - 位图未在 ListView 中显示 : Images from SD Card

Question

我一直在努力，因为 SD 卡中的位图没有显示在 ListView 中。主要问题是将位图包含在 hashmap 中(map.put(TAG_ICON, bm))，以便可以将其填充到 Listview 中。我还打印了位图值android.graphics.Bitmap@41c4c650，并显示位图宽度:256。我只想将图像包含在下面的 ListView 中。希望听到您建议的解决方案。谢谢。菜鸟在这里。

日志猫:

resolveUri failed on bad bitmap uri: android.graphics.Bitmap@41c15540
 06-26 16:39:56.559: I/System.out(2312): resolveUri failed on bad bitmap uri: 
 06-26 16:45:48.989: D/Bitmap not Null(2798): android.graphics.Bitmap@41c4c650

Java

    //In the Main Activity just fetch all the data from MYSql
    //Then save it to the database
    //After saving, then do an intent to display the menu 
public class MainActivity extends ListActivity {

    // Progress Dialog
            private ProgressDialog pDialog;
             Button bMain;



            // Creating JSON Parser object
            JSONParser jParser = new JSONParser();

            ArrayList<HashMap<String, ?>> productsList;

            // url to get all products list
            private static String url_all_products = "";

            // JSON Node names
            private static final String TAG_SUCCESS = "success";
            private static final String TAG_PRODUCTS = "products";
            private static final String TAG_PID = "pid";
            private static final String TAG_NAME = "name";
            private static final String TAG_IMAGE_NAME = "imageName";
            private static final String TAG_ICON=null;
            // products JSONArray
            JSONArray products = null;


            Bitmap bm =null;



    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);



        //1*; 1.5*;2*;3;
        //Identify the screen resolution
        int screenSize = getResources().getConfiguration().screenLayout &
                Configuration.SCREENLAYOUT_SIZE_MASK;

        switch(screenSize) {
            case Configuration.SCREENLAYOUT_SIZE_LARGE:
                setContentView(R.layout.activity_main3);
                Toast.makeText(this, "Large screen: "+screenSize,Toast.LENGTH_LONG).show();

                File folder = new File(Environment.getExternalStorageDirectory() + "/FinalTestforDatabase");
                boolean success1 = true;
                if (!folder.exists()) {
                    success1 = folder.mkdir();
                }
                if (success1) {
                    Toast.makeText(MainActivity.this, "Success: ",Toast.LENGTH_LONG).show();
                } else {
                    Toast.makeText(MainActivity.this, "Fail  ",Toast.LENGTH_LONG).show();
                }



             // Hashmap for ListView
                productsList = new ArrayList<HashMap<String, ?>>();
                //bMain = (Button) findViewById(R.id.main);

                // Loading products in Background Thread
                new LoadAllProducts().execute();

                if(bm!=null)
                {
                ImageView img = (ImageView)findViewById(R.id.imageView1);
                img.setImageBitmap(bm);
                }
                // Get listview
                ListView lv = getListView();
                LayoutAnimationController controller = AnimationUtils.loadLayoutAnimation(this, R.anim.animlistview);
                lv.setLayoutAnimation(controller);

                // on seleting single product
                // launching Edit Product Screen
                lv.setOnItemClickListener(new OnItemClickListener() {

                    @Override
                    public void onItemClick(AdapterView<?> parent, View view,
                            int position, long id) {
                        // getting values from selected ListItem
                        String pid = ((TextView) view.findViewById(R.id.pid)).getText()
                                .toString();

                        // Starting new intent
                        Intent in = new Intent(getApplicationContext(),
                                AlphaInActivity.class);
                        // sending pid to next activity
                        in.putExtra("TAG_PID", pid);

                        // starting new activity and expecting some response back
                        startActivityForResult(in, 100);
                        //Toast.makeText(this.getBaseContext(),pid, 
                                //Toast.LENGTH_SHORT).show();
                    }
                });



                break;
            case Configuration.SCREENLAYOUT_SIZE_NORMAL:
                setContentView(R.layout.activity_main2);
                Toast.makeText(this, "Normal screen",Toast.LENGTH_LONG).show();
                break; 
            case Configuration.SCREENLAYOUT_SIZE_SMALL:
                setContentView(R.layout.activity_main2);
                Toast.makeText(this, "Small screen",Toast.LENGTH_LONG).show();
                break;
            default:
                Toast.makeText(this, "Screen size is neither large, normal or small" , Toast.LENGTH_LONG).show();

        }
    }

    /**
     * Background Async Task to Load all product by making HTTP Request
     * */
    class LoadAllProducts extends AsyncTask<String, String, String> {

        /**
         * Before starting background thread Show Progress Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            pDialog = new ProgressDialog(MainActivity.this);
            pDialog.setMessage("Loading products. Please wait...");
            pDialog.setIndeterminate(false);
            pDialog.setCancelable(false);
            pDialog.show();
        }

        /**
         * getting All products from url
         * */
        protected String doInBackground(String... args) {
            // Building Parameters
            List<NameValuePair> params = new ArrayList<NameValuePair>();
            // getting JSON string from URL
            JSONObject json = jParser.makeHttpRequest(url_all_products, "GET", params);

            // Check your log cat for JSON reponse
            //Log.d("All Products: ", json.toString());

            try {
                // Checking for SUCCESS TAG
                int success = json.getInt(TAG_SUCCESS);

                if (success == 1) {
                    // products found
                    // Getting Array of Products
                    products = json.getJSONArray(TAG_PRODUCTS);



                    // looping through All Products
                    for (int i = 0; i < products.length(); i++) {
                        JSONObject c = products.getJSONObject(i);


                         byte[] decodedString = Base64.decode(c.getString(TAG_IMAGE_NAME), Base64.DEFAULT);
                        Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length);

                        String fileN = (i+1)+".jpg";

                        OutputStream fOut = null;
                        File file = new File(Environment.getExternalStorageDirectory() + "/FinalTestforDatabase/",fileN);
                            try {
                                fOut = new FileOutputStream(file);
                            } catch (FileNotFoundException e1) {
                                // TODO Auto-generated catch block
                                e1.printStackTrace();
                            }
                            decodedByte.compress(Bitmap.CompressFormat.JPEG, 85, fOut);
                            try {
                                fOut.flush();
                            } catch (IOException e2) {
                                // TODO Auto-generated catch block
                                e2.printStackTrace();
                            }
                            try {
                                fOut.close();
                            } catch (IOException e1) {
                                // TODO Auto-generated catch block
                                e1.printStackTrace();
                            }

                try {
                    MediaStore.Images.Media.insertImage(getContentResolver(),file.getAbsolutePath(),file.getName(),file.getName());
                } catch (FileNotFoundException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }

                        String id = c.getString(TAG_PID);
                        String name = c.getString(TAG_NAME);
                        // creating new HashMap
                        HashMap<String, Object> map = new HashMap<String, Object>();

                        String fileName;
                        fileName = (i+1)+".jpg";

                        File f = new File(Environment.getExternalStorageDirectory()+ "/FinalTestforDatabase/", fileName); 
                        FileInputStream is = null; 
                        try { 
                            is = new FileInputStream(f); 
                        } catch (FileNotFoundException e) {
                            Log.d("error: ",String.format( "ShowPicture.java file[%s]Not Found",fileName)); 

                        } 

                        BitmapFactory.Options options = new BitmapFactory.Options();
                          options.inTempStorage = new byte[2*1024];

                        bm= BitmapFactory.decodeStream(is, null, options); 
                        if(bm==null)
                        {
                            Log.d("Bitmap", "Null Value");                          
                        }
                        else
                        {
                            ;
                            Log.d("Bitmap not Null", bm.toString());
                            Log.d("Bitmap Width", ""+bm.getWidth());
                        }

                        //map.put(TAG_ICON, bm);
                        map.put(TAG_PID, name);
                        map.put(TAG_NAME, id);




                        // adding HashList to ArrayList
                        productsList.add(map);

                    }
                } else {
                    // no products found
                    // Launch Add New product Activity
                    Intent i = new Intent(getApplicationContext(),
                            MainActivity.class);
                    // Closing all previous activities
                    i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                    startActivity(i);
                }
            } catch (JSONException e) {
                e.printStackTrace();

            }

            return null;
        }

        private Bitmap getbitmap(byte[] bytesArray) {

            try{

            byte[] decodedString2 = Base64.decode(bytesArray, Base64.DEFAULT);
            Bitmap decodedByte2 = BitmapFactory.decodeByteArray(decodedString2, 0,decodedString2.length);

            return decodedByte2;

            }catch(Exception e){e.toString();}
            return null;


        }

        /**
         * After completing background task Dismiss the progress dialog
         * **/
        protected void onPostExecute(String file_url) {
            // dismiss the dialog after getting all products
            pDialog.dismiss();
            // updating UI from Background Thread
            runOnUiThread(new Runnable() {
                public void run() {
                    /**
                     * Updating parsed JSON data into ListView
                     * */


                    ListAdapter adapter = new SimpleAdapter(
                        MainActivity.this, productsList,
                            R.layout.list_item, new String[] {TAG_ICON, TAG_PID,
                                    TAG_NAME},
                            new int[] {R.id.list_image, R.id.pid, R.id.name });
                    //updating listview  R.id.list_image, ,

                    setListAdapter(adapter);
                }
            });

        }

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    public class MyViewBinder implements ViewBinder {

        public boolean setViewValue(View view, Object data, String textRepresentation) {

            if ((view instanceof ImageView) & (data instanceof Bitmap)) {

                ImageView iv = (ImageView) view;

                Bitmap bm = (Bitmap) data;

                iv.setImageBitmap(bm);

                return true;

            }
            return false;
        }

    }
}

Answer 1

使用

adapter.setViewBinder(new MyViewBinder());



 public class MyViewBinder implements ViewBinder {

    @Override
    public boolean setViewValue(View view, Object data,

    String textRepresentation) {

        if ((view instanceof ImageView) & (data instanceof Bitmap)) {

            ImageView iv = (ImageView) view;

            Bitmap bm = (Bitmap) data;

            iv.setImageBitmap(bm);

            return true;

        }
        return false;
    }

}