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简介

今天主要完成专题和推荐模块。专题是用listview显示一组图片，推荐是飞入飞出的效果。

效果图

怎么给轮播图设置点击事件 ？

昨天添加了循环滚动的轮播图，但是没有添加点击事件，我们平时看到的app都是点击轮播图然后跳转到新界面，其实就是给轮播图的ImageView添加点击事件而已。

效果图

代码：轮播图中的ViewPager的adapter

public class BannerPagerAdapter extends BasePagerAdapter
   
     {
       public BannerPagerAdapter(List
    
      list) {        super(list);    }    @Override    public Object instantiateItem(ViewGroup container, final int position) {        ImageView iv = new ImageView(container.getContext());        ImageLoader.getInstance().displayImage(NetUrl.IMAGE_PREFIX + list.get(position), iv, ImageLoaderOptions.pagerOptions);        LayoutParams params = new LayoutParams();        params.width = LayoutParams.MATCH_PARENT;        params.height = LayoutParams.MATCH_PARENT;        container.addView(iv,params);        //给imageview添加点击事件        iv.setOnClickListener(new OnClickListener() {            @Override            public void onClick(View v) {                ToastUtil.showShortToast("position="+position+"url = "+NetUrl.IMAGE_PREFIX + list.get(position));            }        });        return iv;    }}
    
   

自定义属性

参考：

第一步：在attrs.xml中声明自定义属性

第二步：使用自定义属性

第三步：从命名空间中获取自定义的属性

//都可以//      String namespace = "http://schemas.android.com/apk/res/ratioimageview";String namespace = "http://schemas.android.com/apk/res/com.cqc.googleplay";ratio = attrs.getAttributeFloatValue(namespace, "ratio", 2.42f);//获取xml中的自定义属性的值

RatioImageView：动态设置图片的比

学会了自定义属性，我们才可以在RatioImageView使用它

效果图

代码

public class RatioImageView extends ImageView {
       private float ratio =0f;//图片的宽高比    private int makeMeasureSpec;    public RatioImageView(Context context, AttributeSet attrs, int defStyle) {        super(context, attrs, defStyle);    }    public RatioImageView(Context context, AttributeSet attrs) {        super(context, attrs);        String namespace = "http://schemas.android.com/apk/res/ratioimageview";        ratio = attrs.getAttributeFloatValue(namespace, "ratio", 2.42f);//获取xml中的自定义属性的值    }    public RatioImageView(Context context) {        super(context);    }    @Override    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {        int width = MeasureSpec.getSize(widthMeasureSpec);        if (ratio != 0) {            float height = width / ratio;            heightMeasureSpec = MeasureSpec.makeMeasureSpec((int) height, MeasureSpec.EXACTLY);        }         super.onMeasure(widthMeasureSpec, heightMeasureSpec);    }}

SubjectFrag.java和AppFrag差不多，不再展示。

推荐：

参考：

public class RecommendFrag extends Fragment {
       private static final String TAG = "RecommendFrag";    private ContentPager contentPager;    private List
   
     list = new ArrayList
    
     ();    private StellarMapAdapter adapter;    private int padding = 10;    private StellarMap map;    @Override    public View onCreateView(LayoutInflater inflater, ViewGroup container,            Bundle savedInstanceState) {        contentPager = new ContentPager(getActivity()) {            @Override            public Object requestData() {                return getData();            }            @Override            public View createSuccessView() {                return getSuccessView();            }        };        return contentPager;    }    protected View getSuccessView() {        int padding = (int) CommonUtil.getDimension(R.dimen.recommend_frag_padding);        map = new StellarMap(getActivity());        map.setInnerPadding(padding, padding, padding, padding);        return map;    }    protected Object getData() {        String json = HttpHelper.get(NetUrl.RECOMMEMD);        List textList = (List
     
      ) GsonUtil.jsonToList(json, new TypeToken
      
       
        >() {}.getType());        list.addAll(textList);        CommonUtil.runOnUIThread(new Runnable() {            @Override            public void run() {                adapter = new  StellarMapAdapter(list, getActivity());                  map.setAdapter(adapter);                map.setGroup(0, true); //默认显示第几组数据                map.setRegularity(15, 15); //X Y方向上的密度          }        });        return json;    }}
       
      
     
    
   

怎么随机设置TextView的字体大小和颜色？

Random random = new Random();tv.setTextSize(TypedValue.COMPLEX_UNIT_SP, random.nextInt(5)+15);//[15,20)int red = random.nextInt(150)+50;//[150,200)int green = random.nextInt(150)+50;//[150,200)int blue = random.nextInt(150)+50;//[150,200)int textColor = Color.rgb(red, green, blue);tv.setTextColor(textColor);

源码