Android Support Library View Pager framework technical principles and actual combat k)

Android Support Library View Pager framework technical analysis and actual combat The View Page framework in Android Support Library is a powerful tool for displaying multiple pages in Android applications.It provides a container that can slide pagination, which can browse different page content by sliding left and right.This article will analyze the technical principles of the View Pager framework and provide some actual combat examples. The principle of the View Page framework is based on the Adapter design mode.It requires an adapter as a data source to provide a view required for each page.Adapter must inherit the Pageradapter interface and implement four of them: GetCount (), InstantiaTeitem (), Destroyitem (), and isViewFromobject (). First, the getCount () method is used to specify the number of pages in View Pages.This method should return the number of pages you need to display your application. Next, the InstantiatedEM () method is called when it is created on each page.In this method, you need to create a corresponding view based on the Position parameter and add it to the View Pager.Usually, you can expand views from layout files with layoutinflator. Destroyitem () method is called when the page is destroyed.It needs to remove the corresponding view from the View Pages. Finally, the ISViewFromobject () method is used to determine whether it is composed of a page.Under normal circumstances, you can directly use this method to implement this method. The following is a simple example code that shows how to use the View Page framework to create a sliding container containing three pages: public class MyPagerAdapter extends PagerAdapter { private Context mContext; public MyPagerAdapter(Context context) { mContext = context; } @Override public int getCount() { return 3; } @Override public Object instantiateItem(ViewGroup container, int position) { LayoutInflater inflater = LayoutInflater.from(mContext); View view = inflater.inflate(R.layout.item_page, container, false); // Set the corresponding page content according to the posity container.addView(view); return view; } @Override public void destroyItem(ViewGroup container, int position, Object object) { container.removeView((View) object); } @Override public boolean isViewFromObject(View view, Object object) { return view == object; } } In the above example, we created a custom adapter called MyPageradapter.The number of pages is specified in the getCount () method of 3.In the InstantiatedItem () method, we used Layoutinflator to expand a view from the layout file item_page and add it to the View Page.In the Destroyitem () method, we need to remove the corresponding view from the View Pages. Through the following code, you can associate View Pages with custom adapter and add it to the layout: ViewPager viewPager = findViewById(R.id.viewPager); MyPagerAdapter adapter = new MyPagerAdapter(this); viewPager.setAdapter(adapter); Now, you have learned about the technical principles of Android Support Library View Pager framework, and learn how to use it to create a sliding container.You can customize adapters as needed and add appropriate views and data to meet your application needs.Enjoy the page with rich functioning!