学步园

最近在研究如何做出仿微信，仿新浪等应用，第一次安装使用的使用展示应用程序的新特性和用法。

实现功能：左右手势滑屏

    底部小圆点随当前显示页跳动

    浮动按钮显示。当触屏事件发生显示，否则就渐渐消失

先转个文章：http://blog.csdn.net/feng88724/article/details/6973662

第一种： ViewFlipper + GestureDetector

第二种： ActivityGroup +   GestureDetector

第三种： ViewPager  (Android3.0+)

第四种： ViewFlow (开源项目)

话不多说，先放上效果图

向右滑动，或者点击按钮向右

怎么样，是不是很心动~~~！哈哈、

实现左右滑屏是需要一个叫做ViewPager的东西。具体ViewPager怎么用我就不赘述了。（PS注意导入ViewPager的兼容包)

接下来是代码：

首先在main.xml中声明ViewPager：

     <LinearLayout
        android:id="@+id/linearLayout01"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical" >
	    <android.support.v4.view.ViewPager
	        android:id="@+id/guidePages"
	        android:layout_width="fill_parent"
	        android:layout_height="fill_parent"/>
    	
	   </LinearLayout>

和一个viewGroup放小圆点

    <LinearLayout  
        android:id="@+id/viewGroup"  
        android:layout_width="fill_parent"  
        android:layout_height="wrap_content"  
        android:layout_alignParentBottom="true"  
        android:layout_marginBottom="40dp"  
        android:gravity="center_horizontal"  
        android:orientation="horizontal" >  
        
    </LinearLayout>

接着在item01.xml等几个xml中放置要显示的图片,因为几个都一样，就不都贴上来了。

        <ImageView
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:background="@drawable/feature_guide_0" >

        </ImageView>

接下来是核心代码：

public class GuideViewActivity extends Activity {
	

	private ViewPager viewPager;  
	 private ArrayList<View> pageViews;  
	 private ImageView imageView;  
	 private ImageView[] imageViews; 
	// 包裹滑动图片LinearLayout
	 private ViewGroup main;
	// 包裹小圆点的LinearLayout
	 private ViewGroup group;
	 //左箭头按钮
	 private ImageView imageViewLeft;
	 //右箭头按钮
	 private ImageView imageViewRight;
	 //当前页码
	 private int currentIndex;
	 
	 //ImageView的alpha值   
	 private int mAlpha = 0;
	 private boolean isHide;
	 
	    
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
    	
        super.onCreate(savedInstanceState);

        //将要显示的图片放到ArrayList当中，存到适配器中
        LayoutInflater inflater = getLayoutInflater();  
        pageViews = new ArrayList<View>();  
        pageViews.add(inflater.inflate(R.layout.item01, null));

	...     

        imageViews = new ImageView[pageViews.size()];  
        main = (ViewGroup)inflater.inflate(R.layout.main, null);  
        
        group = (ViewGroup)main.findViewById(R.id.viewGroup);  
        viewPager = (ViewPager)main.findViewById(R.id.guidePages);  
        imageViewLeft = (ImageView)main.findViewById(R.id.imageView1);
        imageViewRight = (ImageView)main.findViewById(R.id.imageView2);
        imageViewLeft.setAlpha(0);
        imageViewRight.setAlpha(0);
        
        //将小圆点放到imageView数组当中
        for (int i = 0; i < pageViews.size(); i++) {  
            imageView = new ImageView(GuideViewActivity.this);  
            imageView.setLayoutParams(new LayoutParams(20,20));  
            imageView.setPadding(20, 0, 20, 0);  
            imageViews[i] = imageView;  
            
            if (i == 0) {  
            	//默认选中第一张图片
                imageViews[i].setBackgroundResource(R.drawable.page_indicator_focused);  
            } else {  
                imageViews[i].setBackgroundResource(R.drawable.page_indicator);  
            }  
            
            group.addView(imageViews[i]);  
        }  
        
        setContentView(main);
        
        viewPager.setAdapter(new GuidePageAdapter());  
        viewPager.setOnPageChangeListener(new GuidePageChangeListener());
        imageViewLeft.setOnClickListener(new ButtonListener());
        imageViewRight.setOnClickListener(new ButtonListener());
    }
    
    //左右切换屏幕的按钮监听器
    class ButtonListener implements OnClickListener{

		@Override
		public void onClick(View v) {
			// TODO Auto-generated method stub
			int showNext=0;
			if(v.getId() == R.id.imageView1) {
				System.out.println("点击了向左的按钮");
				if(currentIndex ==0 )
					showNext = currentIndex;
				else
					showNext = currentIndex-1;
				viewPager.setCurrentItem(showNext);
			}
			if(v.getId() == R.id.imageView2){
				System.out.println("点击了向右的按钮");
				if(currentIndex == imageViews.length)
					showNext = currentIndex;
				else
					showNext = currentIndex+1;
				viewPager.setCurrentItem(showNext);
			}
				System.out.println("当前页码："+showNext);
			
		}
    	
    }
    
    /**
     * 设置按钮渐显效果
     */
    private Handler mHandler = new Handler()
    {
        public void handleMessage(Message msg) {
            if(msg.what==1 && mAlpha<255){           
                //通过设置不透明度设置按钮的渐显效果
                mAlpha += 50;
                
                if(mAlpha>255)
                    mAlpha=255;
                
                imageViewLeft.setAlpha(mAlpha);
                imageViewLeft.invalidate();
                imageViewRight.setAlpha(mAlpha);
                imageViewRight.invalidate();
                
                if(!isHide && mAlpha<255)
                    mHandler.sendEmptyMessageDelayed(1, 100);
            }else if(msg.what==0 && mAlpha>0){
                mAlpha -= 3;
                
                if(mAlpha<0)
                    mAlpha=0;
                imageViewLeft.setAlpha(mAlpha);
                imageViewLeft.invalidate();
                imageViewRight.setAlpha(mAlpha);
                imageViewRight.invalidate();
                
                if(isHide && mAlpha>0)
                    mHandler.sendEmptyMessageDelayed(0, 2);
            }            
        }
    };
    
    private void showImageButtonView(){
        isHide = false;
        mHandler.sendEmptyMessage(1);
    }
    
    private void hideImageButtonView(){
        new Thread(){
            public void run() {
                try {
                    isHide = true;
                    mHandler.sendEmptyMessage(0);
                } catch (Exception e) {
                    ;
                }
            }
        }.start();
    }
    




	@Override
	public boolean dispatchTouchEvent(MotionEvent ev) {
		System.out.println("this is dispatch");
		System.out.println("触碰屏幕");
        switch (ev.getAction()) {
            case MotionEvent.ACTION_MOVE:
            case MotionEvent.ACTION_DOWN:
                showImageButtonView();            
                break;
            case MotionEvent.ACTION_UP:
                hideImageButtonView();                
                break;
        }
        
        
		return super.dispatchTouchEvent(ev);
	}

	// 指引页面数据适配器,实现适配器方法
    class GuidePageAdapter extends PagerAdapter {  
  	  
        @Override  
        public int getCount() {  
            return pageViews.size();  
        }  
  
        @Override  
        public boolean isViewFromObject(View arg0, Object arg1) {  
            return arg0 == arg1;  
        }  
  
        @Override  
        public int getItemPosition(Object object) {  
            // TODO Auto-generated method stub  
            return super.getItemPosition(object);  
        }  
  
        @Override  
        public void destroyItem(View arg0, int arg1, Object arg2) {  
            // TODO Auto-generated method stub  
            ((ViewPager) arg0).removeView(pageViews.get(arg1));  
        }  
  
        @Override  
        public Object instantiateItem(View arg0, int arg1) {  
            // TODO Auto-generated method stub  
            ((ViewPager) arg0).addView(pageViews.get(arg1));  
            return pageViews.get(arg1);  
        }  
  
        @Override  
        public void restoreState(Parcelable arg0, ClassLoader arg1) {  
            // TODO Auto-generated method stub  
  
        }  
  
        @Override  
        public Parcelable saveState() {  
            // TODO Auto-generated method stub  
            return null;  
        }  
  
        @Override  
        public void startUpdate(View arg0) {  
            // TODO Auto-generated method stub  
  
        }  
  
        @Override  
        public void finishUpdate(View arg0) {  
            // TODO Auto-generated method stub  
  
        }  
    } 
    
 // 指引页面更改事件监听器,左右滑动图片时候，小圆点变换显示当前图片位置
    class GuidePageChangeListener implements OnPageChangeListener {  
    	  
        @Override  
        public void onPageScrollStateChanged(int arg0) {  
            // TODO Auto-generated method stub  
  
        }  
  
        @Override  
        public void onPageScrolled(int arg0, float arg1, int arg2) {  
            // TODO Auto-generated method stub  
  
        }  
  
        @Override  
        public void onPageSelected(int arg0) {  
        	currentIndex = arg0;
            for (int i = 0; i < imageViews.length; i++) {  
                imageViews[arg0].setBackgroundResource(R.drawable.page_indicator_focused);
                
                if (arg0 != i) {  
                    imageViews[i].setBackgroundResource(R.drawable.page_indicator);  
                }  
            }
        }  
    }  
}

啊~到这里就都实现了~