【发布时间】:2015-10-24 18:44:06
【问题描述】:
我创建了一个 android 应用程序,用于在 gridview 中显示在线图像。该应用程序运行良好,图像显示在 GridView 中。问题是当我们单击 GridView 中的特定图像时,我想在默认图像查看器中显示图像。
谁能告诉我一些建议
我的代码如下所示
public class MainActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
setContentView(R.layout.activity_main);
GridView gridview = (GridView) findViewById(R.id.gridView1);
gridview.setAdapter(new ImageAdapter(this));
gridview.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
Intent mInDisplay = new Intent(MainActivity.this, MainActivity.class);
// how to show the selected image in default image viewer
}
});
}
public class ImageAdapter extends BaseAdapter {
/** The parent context */
private Context myContext;
/** URL-Strings to some remote images. */
private String[] myRemoteImages = {
"http://www.example.com/uploads/gallery/sample1.jpg",
"http://www.example.com//uploads/gallery/sample2.jpg",
"http://www.example.com//uploads/gallery/sample3.jpg",
"http://www.example.com//uploads/gallery/sample4.jpg",
"http://www.example.com//uploads/gallery/sample5.jpg",
"http://www.example.com//uploads/gallery/sample6.jpg",
"http://www.example.com//uploads/gallery/sample7.jpg",
"http://www.example.com//uploads/gallery/sample8.jpg",
"http://www.example.com//uploads/gallery/sample9.jpg" };
/** Simple Constructor saving the 'parent' context. */
public ImageAdapter(Context c) {
this.myContext = c;
}
/** Returns the amount of images we have defined. */
public int getCount() {
return this.myRemoteImages.length;
}
/* Use the array-Positions as unique IDs */
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
/**
* Returns a new ImageView to be displayed, depending on the position
* passed.
*/
public View getView(int position, View convertView, ViewGroup parent) {
ImageView i = new ImageView(this.myContext);
try {
/* Open a new URL and get the InputStream to load data from it. */
URL aURL = new URL(myRemoteImages[position]);
URLConnection conn = aURL.openConnection();
conn.connect();
InputStream is = conn.getInputStream();
/* Buffered is always good for a performance plus. */
BufferedInputStream bis = new BufferedInputStream(is);
/* Decode url-data to a bitmap. */
Bitmap bm = BitmapFactory.decodeStream(bis);
bis.close();
is.close();
/* Apply the Bitmap to the ImageView that will be returned. */
i.setImageBitmap(bm);
} catch (IOException e) {
i.setImageResource(R.drawable.ic_launcher);
Log.e("DEBUGTAG", "Remtoe Image Exception", e);
}
/* Image should be scaled as width/height are set. */
i.setScaleType(ImageView.ScaleType.FIT_CENTER);
/* Set the Width/Height of the ImageView. */
i.setLayoutParams(new GridView.LayoutParams(150, 150));
return i;
}
/**
* Returns the size (0.0f to 1.0f) of the views depending on the
* 'offset' to the center.
*/
public float getScale(boolean focused, int offset) {
/* Formula: 1 / (2 ^ offset) */
return Math.max(0, 1.0f / (float) Math.pow(2, Math.abs(offset)));
}
}
}
【问题讨论】:
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为什么要投反对票?....我做错了吗
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标签: java android image gridview