android imageswitcher gallery 根据数据库内图片名字进行查看/删除

layout/imageswitch.xml

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="fill_parent"

    android:layout_height="fill_parent" >



    <ImageSwitcher

        android:id="@+id/arc_hf_img_switcher"

        android:layout_width="fill_parent"

        android:layout_height="fill_parent"

        android:layout_alignParentLeft="true"

        android:layout_alignParentTop="true" />



    <LinearLayout

        android:id="@+id/linearLayout1"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:layout_alignParentBottom="true"

        android:layout_alignParentLeft="true"

        android:gravity="center" >



        <Gallery

            android:id="@+id/arc_hf_img_gallery"

            android:layout_width="fill_parent"

            android:layout_height="60dp"

            android:layout_weight="1"

            android:background="#55000000"

            android:gravity="center_vertical"

            android:spacing="16dp" />



        <Button

            android:id="@+id/arc_hf_img_btnDel"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_marginRight="30dp"

            android:text="@string/arc_hf_img_btnDel" />



        <Button

            android:id="@+id/arc_hf_img_btnBack"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:layout_marginRight="30dp"

            android:text="@string/arc_hf_img_btnBack" />

    </LinearLayout>



</RelativeLayout>

ImgSwitch.java

public class ImgSwitch extends Activity implements OnItemSelectedListener,

        ViewFactory {

    private final String DATABASE_PATH = Environment

            .getExternalStorageDirectory().getAbsolutePath() + "/hfdatabase";

    private final String DATABASE_FILENAME = "hf_database.db";

    private final String TABLE_NAME = "HF_IMG_THEME";

    private final String strImgPath = Environment.getExternalStorageDirectory()

            .toString() + "/dlion/";// 存放照片的文件夹

    private SQLiteDatabase db;

    private ImageSwitcher is;

    private Gallery gallery;

    private Bitmap[] bitmaps;

    private int[] _ids;

    private String[] imgNames;

    private int parentId;

    public int gPosition = 0;

    private int isPosition = 0;

    private Button btnDel;

    private Button btnBack;



    // 返回键监听，添加关闭数据库功能。

    public void onBackPressed() {

        super.onBackPressed();

        db.close();

        finish();

    }



    @Override

    protected void onCreate(Bundle savedInstanceState) {

        // TODO Auto-generated method stub

        super.onCreate(savedInstanceState);

        setContentView(R.layout.imageswitch);

        db = openDatabase();

        parentId = this.getIntent().getIntExtra("parentId", 0);



        gallery = (Gallery) findViewById(R.id.arc_hf_img_gallery);

        is = (ImageSwitcher) findViewById(R.id.arc_hf_img_switcher);

        is.setFactory(this);



        is.setInAnimation(AnimationUtils.loadAnimation(this,

                android.R.anim.fade_in));

        is.setOutAnimation(AnimationUtils.loadAnimation(this,

                android.R.anim.fade_out));



        btnDel = (Button) findViewById(R.id.arc_hf_img_btnDel);

        btnBack = (Button) findViewById(R.id.arc_hf_img_btnBack);

        btnDel.setOnClickListener(new btnListener());

        btnBack.setOnClickListener(new btnListener());



        initImgs();

    }



    // 按键监听

    class btnListener implements OnClickListener {



        @Override

        public void onClick(View v) {

            // TODO Auto-generated method stub

            switch (v.getId()) {

            case R.id.arc_hf_img_btnBack:

                db.close();

                finish();

                break;

            case R.id.arc_hf_img_btnDel:

                db.delete(TABLE_NAME, "_id=" + _ids[gPosition], null);

                File file = new File(imgNames[gPosition]);

                file.delete();

                Toast.makeText(ImgSwitch.this, imgNames[gPosition] + "删除成功",

                        Toast.LENGTH_SHORT).show();

                initImgs();

                break;

            default:

                break;

            }

        }



    }



    // 初始化图片视图

    private void initImgs() {

        Cursor cursorImgName = db.query(TABLE_NAME, null, "parentId = "

                + parentId, null, null, null, null);

        bitmaps = new Bitmap[cursorImgName.getCount()];

        imgNames = new String[cursorImgName.getCount()];

        _ids = new int[cursorImgName.getCount()];



        // 优化内存

        BitmapFactory.Options options = new BitmapFactory.Options();

        options.inSampleSize = 20;

        for (int i = 0; i < cursorImgName.getCount(); i++) {

            cursorImgName.moveToNext();

            

            // 保存图片组名字、ID、完整路径

            imgNames[i] = strImgPath

                    + cursorImgName.getString(cursorImgName

                            .getColumnIndex("imgName"));

            _ids[i] = cursorImgName.getInt(cursorImgName.getColumnIndex("_id"));

            bitmaps[i] = BitmapFactory.decodeFile(imgNames[i], options);

        }

        gallery.setAdapter(new ImageAdapter(this));

        gallery.setOnItemSelectedListener(this);

        if (gPosition == cursorImgName.getCount()

                && cursorImgName.getCount() >= 1) {

            is.setImageURI(Uri.parse(imgNames[isPosition - 1]));

        } else if (cursorImgName.getCount() == 0) { // 没有图片时，取消删除键监听

            btnDel.setEnabled(false);

        }

    }



    @Override

    public View makeView() {

        // TODO Auto-generated method stub

        ImageView i = new ImageView(this);

        i.setBackgroundColor(0xFF000000);

        i.setScaleType(ImageView.ScaleType.FIT_CENTER);

        i.setLayoutParams(new ImageSwitcher.LayoutParams(

                LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));

        return i;

    }



    // 覆写baseadapter类

    public class ImageAdapter extends BaseAdapter {

        private Context mContext;



        public ImageAdapter(Context c) {

            mContext = c;

        }



        @Override

        public int getCount() {

            // TODO Auto-generated method stub

            return bitmaps.length;

        }



        @Override

        public Object getItem(int position) {

            // TODO Auto-generated method stub

            return position;

        }



        @Override

        public long getItemId(int position) {

            // TODO Auto-generated method stub

            return position;

        }



        @Override

        public View getView(int position, View convertView, ViewGroup parent) {

            // TODO Auto-generated method stub

            gPosition = position;

            ImageView i = new ImageView(mContext);



            i.setImageBitmap(bitmaps[position]);

            i.setAdjustViewBounds(true);

            i.setLayoutParams(new Gallery.LayoutParams(

                    LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));

            return i;

        }

    }



    @Override

    public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2,

            long arg3) {

        // TODO Auto-generated method stub

        isPosition = arg2;

        is.setImageURI(Uri.parse(imgNames[arg2]));

    }



    @Override

    public void onNothingSelected(AdapterView<?> arg0) {

        // TODO Auto-generated method stub



    }



    // 初始化数据库

    private SQLiteDatabase openDatabase() {

        try {

            String databaseFilename = DATABASE_PATH + "/" + DATABASE_FILENAME;

            File dir = new File(DATABASE_PATH);

            if (!dir.exists())

                dir.mkdir();



            if (!(new File(databaseFilename)).exists()) {

                InputStream is = getResources().openRawResource(

                        R.raw.hf_database);

                FileOutputStream fos = new FileOutputStream(databaseFilename);

                byte[] buffer = new byte[8192];

                int count = 0;

                // 开始复制hf_database.db文件

                while ((count = is.read(buffer)) > 0) {

                    fos.write(buffer, 0, count);

                }

            }



            db = SQLiteDatabase.openOrCreateDatabase(databaseFilename, null);

            return db;

        } catch (Exception e) {

            e.printStackTrace();

        }

        return null;

    }



}