如何使用位图数组设置图像视图

Question

我正在做一个通过JSON获取图像URL的演示，在获得ULR后，我正在下载该图像并将它们显示在GridView中。为了存储下载的图像，我正在使用Bitmap数组并将其传递给ImageAdapter。现在我想在ImageView的下一个活动中显示该图像，因为我在第二个活动中使用以下代码。

        // get intent data
    Intent i = getIntent();
    // Selected image id
    int position = i.getExtras().getInt("id");
    ImageAdapter imageAdapter = new ImageAdapter(this);
    ImageView imageView = (ImageView) findViewById(R.id.full_image_view);
    imageView.setBackgroundDrawable(imageAdapter.bm[position]);

但它给了我像The method setImageDrawable(Drawable) in the type ImageView is not applicable for the arguments (Bitmap)这样的错误.请告诉我如何将Bitmap数组中的图像设置为ImageView..

图像适配器类：

    public class ImageAdapter extends BaseAdapter {
    private Context mContext;
    public Bitmap bm[]=new Bitmap[4];
    ImageView imageView;
    // Constructor
    public ImageAdapter(Context c, Bitmap[] bm){
        mContext = c;
        this.bm = bm; 
    }

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

    @Override
    public int getCount() {
        return bm.length;
    }
    @Override
    public Object getItem(int position) {
        return bm[position];
    }
    @Override
    public long getItemId(int position) {
        return 0;
    }
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        imageView = new ImageView(mContext);
        imageView.setImageBitmap(bm[position]);
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setLayoutParams(new GridView.LayoutParams(70, 70));
        return imageView;
    }

}

主类：

    public class AndroidGridLayoutActivity extends Activity {
    public static final  Bitmap bm[]=new Bitmap[4];
    public static  ImageAdapter img;
    public static  String[] imageurls;
    public static  GridView gridView;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.grid_layout);
        Log.d("LOG", "1");
        new GetImageUrls().execute();
        try {
            Thread.sleep(5000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }       
        Log.d("LOG", "7");
        gridView = (GridView) findViewById(R.id.grid_view);
        // Instance of ImageAdapter Class
        Log.d("LOG", "8");
        img = new ImageAdapter(getApplicationContext(), bm);
        Log.d("LOG", "9");
        gridView.setAdapter(img);
        Log.d("LOG", "10");

        /**
         * On Click event for Single Gridview Item
         * */
        gridView.setOnItemClickListener(new OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View v,
                    int position, long id) {
                Log.d("LOG", "11");
                // Sending image id to FullScreenActivity
                Intent i = new Intent(getApplicationContext(), FullImageActivity.class);
                Log.d("LOG", "12");
                // passing array index
                i.putExtra("id", position);
                startActivity(i);
            }
        });
    }
    public class GetImageUrls  extends AsyncTask<Void, Void, Void>
    {
        Context context;
        private ProgressDialog pDialog;
        // URL to get JSON
        private static final String url= "http://xxx.x.xxx/demo/test.json";
        private static final String MAIN = "mainCategory";
        private static final String IMAGE = "mcatimage";
        // JSONArray
        JSONArray loginjsonarray=null;
        //result from url
        protected void onPreExecute() {
            Log.d("LOG", "2");
            // Showing progress dialog
            pDialog = new ProgressDialog(getApplicationContext());
            pDialog.setMessage("Loading...");
            pDialog.setCancelable(false);
            //pDialog.show();
            Log.d("LOG", "3");
        }
        protected Void doInBackground(Void... arg) {
            Log.d("LOG", "4");
            // Creating service handler class instance
            ServiceHandler sh = new ServiceHandler();
            Log.d("LOG", "5");
             // Making a request to url and getting response
            String jsonstr = sh.makeServiceCall(url, ServiceHandler.POST, null);
            Log.d("Response: ", ">"+jsonstr);
            if(jsonstr!=null)
            {
                try {
                        JSONObject jsonObj =new JSONObject(jsonstr);
                        loginjsonarray=jsonObj.getJSONArray(MAIN);
                        imageurls=new String[loginjsonarray.length()];
                        for(int i=0;i<loginjsonarray.length();i++){
                            JSONObject l=loginjsonarray.getJSONObject(i);
                            imageurls[i]=l.getString(IMAGE);
                            Log.d("imageurls: ", imageurls[i]);
                        }
                        for(int i=0;i<imageurls.length;i++)
                        {   
                            bm[i]=DownloadImage(imageurls[i]);
                            Log.d("LOG", bm[i].toString());
                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
            }else{
                Toast.makeText(context,"Check your Internet Connection",Toast.LENGTH_SHORT).show();
            }
            return null;
        }

        public Bitmap DownloadImage(String STRURL) {
            Bitmap bitmap = null;
            InputStream in = null;       
            try {
                    int response = -1;
                    URL url = new URL(STRURL);
                    Log.d("DownloadImage: ", url.toString());
                    URLConnection conn = url.openConnection();
                    if (!(conn instanceof HttpURLConnection))             
                        throw new IOException("Not an HTTP connection");
                    try{
                        HttpURLConnection httpConn = (HttpURLConnection) conn;
                        httpConn.setAllowUserInteraction(false);
                        httpConn.setInstanceFollowRedirects(true);
                        httpConn.setRequestMethod("GET");
                        httpConn.connect();
                        response = httpConn.getResponseCode();  
                        Log.d("DownloadImage response: ", Integer.toString(response));
                        if (response == HttpURLConnection.HTTP_OK) {
                            in = httpConn.getInputStream();
                            Log.d("DownloadImage: ", in.toString());
                        }                    
                    } catch (Exception ex) {
                        throw new IOException("Error connecting"); 
                    }
                    bitmap = BitmapFactory.decodeStream(in);
                    Log.d("DownloadImage Bitmap: ", bitmap.toString());
                    in.close();
                }catch (IOException e1) {
                    e1.printStackTrace();
                }
            Log.d("LOG", "6");
            return bitmap; 
        }
        protected void onPostExecute(Integer result) {
            // Dismiss the progress dialog
            if(pDialog.isShowing()){
                pDialog.dismiss();
            }
        }
    }
}

完整活动类：

public class FullImageActivity extends Activity {

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.full_image);
    // get intent data
    Intent i = getIntent();
    // Selected image id
    int position = i.getExtras().getInt("id");
    Log.d("Position", Integer.toString(position));
    ImageAdapter imageAdapter = new ImageAdapter(this);
    ImageView imageView = (ImageView) findViewById(R.id.full_image_view);
    imageView.setImageBitmap(imageAdapter.bm[position]);
}

}

Answer 1

它如此简单的方法使用setImageBitmap。

imageView.setImageBitmap(imageAdapter.bm[position]);

Answer 2

你应该使用 setImageBitmap （Bitmap bm） 方法，该方法将位图设置为此 ImageView 的内容。

所以你的代码将是，

imageView.setImageBitmap(imageAdapter.bm[position]);

文档。

Answer 3

imageView.setImageBitmap(imageAdapter.bm[position]);

Answer 4

在这里，

我为您提供我的应用程序代码，该代码与具有int位置的可绘制资源的库一起使用，根据您的需要对其进行修改，应该与您的代码一起使用。

我对画廊的意图是：

@Override
public void onItemClick(AdapterView<?> parent, View  view, int position, long id) {
    int selectedId = imgs[position]; 
    Intent intent = new Intent(Gallery3DActivity.this,MainActivity.class);
    intent.putExtra("imageId", selectedId);
    startActivity(intent);
}

在主活动中，我收到意图并将其设置在图像视图上：

Intent avatar = getIntent(); 
int imageId = avatar.getIntExtra("imageId", -0); 
// -0 would be a default value
// -1 will crash with a missing resource
if (getIntent().getExtras() != null) {
    Avatar.setImageResource(imageId);
    savedAvatar.setImageResource(imageId);
} else {
    Avatar.setImageResource(R.mipmap.ic_launcher);
}

您的代码与我的代码相似，但是您从url中获取它到位图，我从可绘制资源中获取它，在活动Java上为名称和位置设置了长ID列表，我选择了我想设置为头像的那个，他们将其传递给主要活动，并定义包含可绘制缓存的意图名称到图像视图， 在按钮单击后，我转换为位图，位图转换为字符串，字符串转换为图像以在启动主要活动时恢复图像视图视图，并将字符串保存到共享首选项，即使在关闭应用程序后也能再次恢复图像视图视图。

祝你好运