Android特效第三篇：自定义Gallery实战(仿网易) .

Android系统提供了一个Gallery画廊控件，在项目很多时候都会用到Gallery，比如新浪首页的广告，网易看客户端首页等随处可见，今天我自己定义了一个仿网易的Gallery与大家共享。
     首先请看效果图：

                                         


代码：

[java]
view plaincopyprint?

package com.jefry.gallery;  
  
import java.util.ArrayList;  
import java.util.List;  
  
import android.app.Activity;  
import android.content.Context;  
import android.content.res.Resources;  
import android.graphics.Bitmap;  
import android.graphics.BitmapFactory;  
import android.util.AttributeSet;  
import android.view.LayoutInflater;  
import android.view.View;  
import android.view.ViewGroup;  
import android.widget.AdapterView;  
import android.widget.BaseAdapter;  
import android.widget.FrameLayout;  
import android.widget.Gallery;  
import android.widget.ImageView;  
import android.widget.LinearLayout;  
import android.widget.TextView;  
  
/** 
 * @author jefry 
 * 
 */  
public class MyGallery extends FrameLayout {  
    List<Showing> showings = new ArrayList<Showing>();  
    private static final double GALLERY_IMAGE_HORIZONTAL_RATIO = 1.0;  
    private static final double GALLERY_IMAGE_VERTICAL_RATIO = 1.0;  
    private static final int GALLERY_SPACING = 2;  
    private Context mContext;  
    private PromotionImages promotionImages;  
    private LinearLayout mBottomLayout;  
    private TextView tips;  
    private int mPcount;  
    private ImageView[] icons;  
    public MyGallery(Context context) {  
        super(context);  
    }  
  
    public MyGallery(Context context, AttributeSet attrs) {  
        super(context, attrs);  
        mContext = context;  
        promotionImages = new PromotionImages(context);  
        LayoutParams layoutParams = new LayoutParams(android.view.ViewGroup.LayoutParams.FILL_PARENT,android.view.ViewGroup.LayoutParams.FILL_PARENT);  
        layoutParams.bottomMargin = 20;  
        this.addView(promotionImages, layoutParams);  
        LayoutInflater inflater = ((Activity) context).getLayoutInflater();  
        View indicator = inflater.inflate(R.layout.promotion_hint,null);  
        this.addView(indicator);  
        //   
        mBottomLayout = (LinearLayout) indicator.findViewById(R.id.promotion_index_layout);  
        tips      = (TextView) indicator.findViewById(R.id.promotion_tip);  
        initBottomIcons();  
    }  
      
      
      
  
    class PromotionImages extends Gallery {  
         
        PromotionImagesAdapter promotionAdapter;  
        public PromotionImages(Context context) {  
            super(context);  
            this.setSpacing(GALLERY_SPACING);  
            promotionAdapter = new PromotionImagesAdapter(context);  
            this.setAdapter(promotionAdapter);  
              
            this.setOnItemSelectedListener(new OnItemSelectedListener() {  
                  
                public void onItemSelected(AdapterView<?> parent, View view,  
                        int position, long id) {  
                     update(position);  
                }  
  
          
                public void onNothingSelected(AdapterView<?> parent) {  
                      
                }  
            });  
        }  
          
          
        private final void update(int selected) {  
            tips.setText(showings.get(selected).getText());  
            for (int i = 0; i < mPcount; i++) {  
                   if (selected == i) {  
                        icons[i].setBackgroundDrawable(getResources().getDrawable(R.drawable.promotion_select_focus));  
                    } else {  
                        icons[i].setBackgroundDrawable(getResources().getDrawable(R.drawable.promotion_select_default));  
                    }  
              }  
            }  
        }  
      
      
       private final void initBottomIcons() {  
         mPcount = showings.size();  
         icons = new ImageView[mPcount];  
         mBottomLayout.removeAllViews();  
         mBottomLayout.setWeightSum(mPcount);  
        //   
        for (int i = 0; i < mPcount; i++) {  
            icons[i] = new ImageView(mContext);  
            if(i == 0) icons[i].setBackgroundDrawable(getResources().getDrawable(R.drawable.promotion_select_focus));  
            else icons[i].setBackgroundDrawable(getResources().getDrawable(R.drawable.promotion_select_default));  
            mBottomLayout.addView(icons[i]);  
        }  
    }  
  
        private final class PromotionImagesAdapter extends BaseAdapter {  
            public PromotionImagesAdapter(Context context) {  
                Resources res = getResources();  
  
                Bitmap bmp = BitmapFactory.decodeResource(res,  
                        R.drawable.test2);  
                Showing show1 = new Showing();  
                show1.setBitmap(bmp);  
                show1.setText("jefry_1");  
  
                Bitmap bmp1 = BitmapFactory.decodeResource(res,  
                        R.drawable.test1);  
                Showing show2 = new Showing();  
                show2.setBitmap(bmp1);  
                show2.setText("jefry_2");  
                  
                Bitmap bmp3 = BitmapFactory.decodeResource(res,  
                        R.drawable.test3);  
                Showing show3 = new Showing();  
                show3.setBitmap(bmp3);  
                show3.setText("jefry_3");  
  
                showings.add(show1);  
                showings.add(show2);  
                showings.add(show3);  
  
            }  
  
              
            public int getCount() {  
                return showings.size();  
            }  
  
              
            public Object getItem(int position) {  
                return position;  
            }  
  
              
            public long getItemId(int position) {  
                return position;  
            }  
  
              
            public View getView(final int position, final View convertView,  
                    ViewGroup parent) {  
                //System.out.println("showings = " + showings.size());
  
                //System.out.println("position=" + position);
  
                final Showing promotion = showings.get(position);  
                ImageView promotionImage = (ImageView) convertView;   
                if (promotionImage == null) {  
                    promotionImage = new ImageView(mContext);  
                    System.out.println("postion=" + position + ",promotion.getBitmap()1 = "+ promotion.getBitmap());  
                }  
                int width = (int) (MyGallery.this.getWidth() * GALLERY_IMAGE_HORIZONTAL_RATIO);  
                int height = (int) (MyGallery.this.getHeight() * GALLERY_IMAGE_VERTICAL_RATIO);  
                promotionImage.setLayoutParams(new Gallery.LayoutParams(width,height));  
                promotionImage.setScaleType(ImageView.ScaleType.CENTER);  
                promotionImage.setScaleType(ImageView.ScaleType.FIT_XY);  
                System.out.println("postion=" + position + ",promotion.getBitmap() = "+ promotion.getBitmap());  
                promotionImage.setImageBitmap(promotion.getBitmap());  
                return promotionImage;  
            }  
        }  
    }  

package com.jefry.gallery;

import java.util.ArrayList;
import java.util.List;

import android.app.Activity;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.FrameLayout;
import android.widget.Gallery;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

/**
* @author jefry
*
*/
public class MyGallery extends FrameLayout {
List<Showing> showings = new ArrayList<Showing>();
private static final double GALLERY_IMAGE_HORIZONTAL_RATIO = 1.0;
private static final double GALLERY_IMAGE_VERTICAL_RATIO = 1.0;
private static final int GALLERY_SPACING = 2;
private Context mContext;
private PromotionImages promotionImages;
private LinearLayout mBottomLayout;
private TextView tips;
private int mPcount;
private ImageView[] icons;
public MyGallery(Context context) {
super(context);
}

public MyGallery(Context context, AttributeSet attrs) {
super(context, attrs);
mContext = context;
promotionImages = new PromotionImages(context);
LayoutParams layoutParams = new LayoutParams(android.view.ViewGroup.LayoutParams.FILL_PARENT,android.view.ViewGroup.LayoutParams.FILL_PARENT);
layoutParams.bottomMargin = 20;
this.addView(promotionImages, layoutParams);
LayoutInflater inflater = ((Activity) context).getLayoutInflater();
View indicator = inflater.inflate(R.layout.promotion_hint,null);
this.addView(indicator);
//
mBottomLayout = (LinearLayout) indicator.findViewById(R.id.promotion_index_layout);
tips	  = (TextView) indicator.findViewById(R.id.promotion_tip);
initBottomIcons();
}

class PromotionImages extends Gallery {

PromotionImagesAdapter promotionAdapter;
public PromotionImages(Context context) {
super(context);
this.setSpacing(GALLERY_SPACING);
promotionAdapter = new PromotionImagesAdapter(context);
this.setAdapter(promotionAdapter);

this.setOnItemSelectedListener(new OnItemSelectedListener() {

public void onItemSelected(AdapterView<?> parent, View view,
int position, long id) {
update(position);
}

public void onNothingSelected(AdapterView<?> parent) {

}
});
}

private final void update(int selected) {
tips.setText(showings.get(selected).getText());
for (int i = 0; i < mPcount; i++) {
if (selected == i) {
icons[i].setBackgroundDrawable(getResources().getDrawable(R.drawable.promotion_select_focus));
} else {
icons[i].setBackgroundDrawable(getResources().getDrawable(R.drawable.promotion_select_default));
}
}
}
}

private final void initBottomIcons() {
mPcount = showings.size();
icons = new ImageView[mPcount];
mBottomLayout.removeAllViews();
mBottomLayout.setWeightSum(mPcount);
//
for (int i = 0; i < mPcount; i++) {
icons[i] = new ImageView(mContext);
if(i == 0) icons[i].setBackgroundDrawable(getResources().getDrawable(R.drawable.promotion_select_focus));
else icons[i].setBackgroundDrawable(getResources().getDrawable(R.drawable.promotion_select_default));
mBottomLayout.addView(icons[i]);
}
}

private final class PromotionImagesAdapter extends BaseAdapter {
public PromotionImagesAdapter(Context context) {
Resources res = getResources();

Bitmap bmp = BitmapFactory.decodeResource(res,
R.drawable.test2);
Showing show1 = new Showing();
show1.setBitmap(bmp);
show1.setText("jefry_1");

Bitmap bmp1 = BitmapFactory.decodeResource(res,
R.drawable.test1);
Showing show2 = new Showing();
show2.setBitmap(bmp1);
show2.setText("jefry_2");

Bitmap bmp3 = BitmapFactory.decodeResource(res,
R.drawable.test3);
Showing show3 = new Showing();
show3.setBitmap(bmp3);
show3.setText("jefry_3");

showings.add(show1);
showings.add(show2);
showings.add(show3);

}

public int getCount() {
return showings.size();
}

public Object getItem(int position) {
return position;
}

public long getItemId(int position) {
return position;
}

public View getView(final int position, final View convertView,
ViewGroup parent) {
//System.out.println("showings = " + showings.size());
//System.out.println("position=" + position);
final Showing promotion = showings.get(position);
ImageView promotionImage = (ImageView) convertView;
if (promotionImage == null) {
promotionImage = new ImageView(mContext);
System.out.println("postion=" + position + ",promotion.getBitmap()1 = "+ promotion.getBitmap());
}
int width = (int) (MyGallery.this.getWidth() * GALLERY_IMAGE_HORIZONTAL_RATIO);
int height = (int) (MyGallery.this.getHeight() * GALLERY_IMAGE_VERTICAL_RATIO);
promotionImage.setLayoutParams(new Gallery.LayoutParams(width,height));
promotionImage.setScaleType(ImageView.ScaleType.CENTER);
promotionImage.setScaleType(ImageView.ScaleType.FIT_XY);
System.out.println("postion=" + position + ",promotion.getBitmap() = "+ promotion.getBitmap());
promotionImage.setImageBitmap(promotion.getBitmap());
return promotionImage;
}
}
}

源码下载：http://download.csdn.net/detail/jefry_xdz/4521377