Android wheel cast control

Amway a banner, used in the project development of the banner, to achieve viewPager infinite round broadcast function, built-in round IndicatorView, support a variety of animation switching.

• Supports one screen with three pages
• Support meizu effects
• Support custom Indicators
• Support for custom views
• Data refresh
• Resolve sliding conflicts such as pull-down refresh, such as nested SwipeRefreshLayout
• Resolve the onPageSelected problem
• Good code encapsulation, see code implementation for more optimization.

If you like it, start supporting itGithub.com/zguop/banne…

The realization of the core idea of the banner is through the count+2 rotation of the idea, it is borrowed from the network red library Github start the largest number of banner library, it seems that the library does not support a screen to display three pages of the effect, there is a slide to the last page blank situation.

A brief statement of the core principles

• NeedCount (6) = count(4) + 2. There are 6 images in the actual rotation, which are stored in the banner corresponding to:

We can see that in the actual index=0 is the last image and index=5 is the first image, we just swipe right to index=5 and go to viewager. SetCurrentItem (1, false); When index=0, use viewpager. setCurrentItem(count, false); Switch to the actual picture of the last one, the transition to achieve a circular effect of round seeding.

• NeedCount (8) = count(4) + 4. The actual number of images in rotation is 8, which is stored in the banner corresponding to:

rendering

Click on the downloadbanner.apkexperience

describe	The picture
For basic functions, please download APK for a smoother experience

describe	Normal style	On both sides of the zoom	Meizu style
Three pages of one screen at a time

rendering	1	2
Indicator View simple code

Using the step

Step 1. Rely on banners

Go to the target address location banner

Step 2.xml

    <com.to.aboomy.banner.Banner
        android:id="@+id/banner"
        android:layout_width="match_parent"
        android:layout_height="250dp"/>
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Step 3. Customize HolderCreator

// Implement HolderCreator interface
public interface HolderCreator {
    View createView(Context context,final int index, Object o);
}

// For example
public class ImageHolderCreator implements HolderCreator {
    @Override
    public View createView(final Context context, final int index, Object o) {
        ImageView iv = new ImageView(context);
        iv.setScaleType(ImageView.ScaleType.FIT_XY);
        Glide.with(iv).load(o).into(iv);
        // Implement the click event internally
        iv.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Toast.makeText(context, index + "", Toast.LENGTH_LONG).show(); }});returniv; }}Copy the code

Step 4. Use Banner in the page

 @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        banner = findViewById(R.id.banner);
        // Use the built-in Indicator
        IndicatorView indicator = new IndicatorView(this)
              .setIndicatorColor(Color.DKGRAY)
              .setIndicatorSelectorColor(Color.WHITE);
        banner.setIndicator(indicator)
              .setHolderCreator(new ImageHolderCreator())
              .setPages(list);
    }
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Simple setup of three pages on one screen

// Set the width of the left and right pages exposed and the width between items
.setPageMargin(UIUtil.dip2px(this.20), UIUtil.dip2px(this.10))
// Built-in ScaleInTransformer, set toggle zoom animation
.setPageTransformer(true.new ScaleInTransformer())
    
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About the ViewPager switch animation

The following two ViewPager toggle animations are integrated in Sample. Please run Sample to check the animation effect, refer to the required ViewPagerTransform and put it into the project, or customize it as required.

ViewPagerTransforms

MagicViewPager

How to customize Indicator

   // Implement Indicator interface
/** * Can implement this interface, custom Indicator can refer to the built-in {@link IndicatorView}
 */
public interface Indicator extends ViewPager.OnPageChangeListener {

    /** ** is called when data initialization is complete@paramPagerCount Pager quantity */
    void initIndicatorCount(int pagerCount);

    /** * returns a View to add to the banner */
    View getView(a);

    /** * The banner is a RelativeLayout. Set the position of the banner within the RelativeLayout, which can be anywhere */
    RelativeLayout.LayoutParams getParams(a);
}

// For example
public class IndicatorView extends View implements Indicator{
       
        @Override
        public void initIndicatorCount(int pagerCount) {
            this.pagerCount = pagerCount;
            setVisibility(pagerCount > 1 ? VISIBLE : GONE);
            requestLayout();
        }
    
        @Override
        public View getView(a) {
            return this;
        }
         /** * Controls the position of Indicator in the Banner, developers implement */
        @Override
        public RelativeLayout.LayoutParams getParams(a) {
            if (params == null) {
                params = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
                params.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
                params.addRule(RelativeLayout.CENTER_HORIZONTAL);
                params.bottomMargin = dip2px(10);
            }
            return params;
        }
        /** * Three methods for synchronizing the callback when the banner is switched */
        @Override
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
            selectedPage = position;
            offset = positionOffset;
            invalidate();
        }
        
        @Override
        public void onPageSelected(int position) {}@Override
        public void onPageScrollStateChanged(int state) {}}Copy the code

Methods provided by the Banner. The Banner does not provide any custom attributes

Built-in IndicatorView usage method introduction, does not provide any custom properties