[Android Development] How to customize arrayadapter

Scenario:

I want to display all the images in the/dcim/camera directory of the SD card to a list. On the left side of each item in this list is the thumbnail of the image, and on the right side is the file name.

Analysis:

This application is very typical.Data BindingAddCustom display.

How can this problem be solved?

1. Customize the list Style

Image_item.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"         android:layout_width="fill_parent"         android:layout_height="fill_parent"         android:orientation="horizontal"> <ImageView     android:id="@+id/item_thumbnail"     android:layout_height="48dip"     android:layout_width="48dip"         /> <TextView     android:id="@+id/item_file_name"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:textAppearance="?android:attr/textAppearanceLarge"     android:minHeight="?android:attr/listPreferredItemHeight"     android:gravity="center_vertical"     android:paddingLeft="5dip"     /></LinearLayout>

2. Custom arrayadapter

Imagelistadapter

Public class imagelistadapter extends arrayadapter <File> {private int resource; Public imagelistadapter (context, int resourceid, list <File> objects) {super (context, resourceid, objects ); // record it and use resource = resourceid later;} public view getview (INT position, view convertview, viewgroup parent) {linearlayout imagelistview; // obtain the data file = getitem (position ); string filename = file. getnam E (); Bitmap bitmap = getbitmapfromfile (File); // when the system displays the list, an adapter is first instantiated (the custom adapter will be instantiated here ). // When manual adaptation is completed, data must be manually mapped. You need to override the getview () method. // The system calls this method when drawing each row of the list. // Getview () has three parameters. // position indicates the rows to be displayed. // covertview indicates the inflate layout from the layout file. // We use the layoutinflater method to extract the defined image_item.xml file into a view instance for display. // Instantiate each component in the XML file (simple findviewbyid () method ). // You can map the data to each component. // If (convertview = NULL) {imagelistview = new linearlayout (getcontext ()); // check the definition of layoutinflater In the android document. // This class is used to instantiate layout XML file into its corresponding view objects. // It is never be used directly -- use getlayoutinflater () or getsystemservice (string) // to retrieve a standard layoutinflater instance that is already hooked up to the current // context and correctly configured for the device you are running on .. for example: String Inflater = context. layout_inflater_service; layoutinflater Vi = (layoutinflater) getcontext (). getsystemservice (Inflater); VI. inflate (resource, imagelistview, true); // This log is called every time you select images. D ("adapter", "convertview is null now");} else {// it is strange that imagelistview = (linearlayout) convertview; log has not been called. D ("adapter", "convertview is not null now");} // fill in custom data imageview = (imageview) imagelistview. findviewbyid (R. id. item_thumbnail); textview = (textview) imagelistview. findviewbyid (R. id. item_file_name); textview. settext (filename); imageview. setimagebitmap (Bitmap); Return imagelistview;} // obtain the bitmap from the file to fill in the private bitmap getbitmapfromfile (File file) {Bitmap bitmap = bitmapfactory. decodefile (file. getabsolutepath (); Return bitmap ;}}

3. Bind data

private void bindFilesToList(File[] files) {         List<File> fileList = new ArrayList<File>();         for(File file : files) {             fileList.add(file);         }        ImageListAdapter adapter = new ImageListAdapter(ImageFilesListActivity.this,                                                         R.layout.image_item,                                                         fileList);         setListAdapter(adapter); }

This is basically the case.