ViewPager+PagerAdapter实现带指示器的引导页
一个简单的引导页,由ViewPager和PagerAdapter组成,供大家参考,具体内容如下
package com.xspacing.viewpager; import java.util.ArrayList; import java.util.List; import android.app.Activity; import android.os.Bundle; import android.support.v4.view.ViewPager; import android.support.v4.view.ViewPager.OnPageChangeListener; import android.util.Log; import android.view.View; import android.view.ViewTreeObserver.OnGlobalLayoutListener; import android.widget.Button; import android.widget.ImageView; import android.widget.LinearLayout; import android.widget.LinearLayout.LayoutParams; import android.widget.RelativeLayout; /** * * @ClassName MainActivity.java * @Description TODO 引导页 * @author Smile * @version v1.0 * @date 2016年9月26日 */ public class MainActivity extends Activity { protected static final String TAG = "MainActivity"; ViewPager mViewPager; List<ImageView> list; private LinearLayout mLinearLayout; // 两个小灰点的距离 private int poitWidth; private ImageView mViewPress; private ImageView mViewNotPress; private Button btnStart; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initViews(); initDatas(); } private void initViews() { mViewPager = (ViewPager) findViewById(R.id.main_view_pager); mLinearLayout = (LinearLayout) findViewById(R.id.main_point); mViewPress = (ImageView) findViewById(R.id.main_red_point_press); btnStart = (Button) findViewById(R.id.main_btn); } private void initDatas() { list = new ArrayList<ImageView>(); final int imageId[] = { R.drawable.a, R.drawable.b, R.drawable.c }; for (int i = 0; i < imageId.length; i++) { ImageView imageView = new ImageView(this); imageView.setBackgroundResource(imageId[i]); list.add(imageView); mViewNotPress = new ImageView(this); mViewNotPress.setImageResource(R.drawable.shape_grey_point_not_press); LayoutParams layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT); if (i != 0) { layoutParams.leftMargin = 20; } mLinearLayout.addView(mViewNotPress, layoutParams); } // 由于在执行onCreate()的时候,界面还没有被绘制完成,所有拿不到poitWidth, // 要拿到视图树,监听视图的绘制完成,才能拿到poitWidth mViewPress.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() { @Override public void onGlobalLayout() { poitWidth = mLinearLayout.getChildAt(1).getLeft() - mLinearLayout.getChildAt(0).getLeft(); Log.i(TAG, poitWidth + ""); } }); mViewPager.setAdapter(new ViewPgerAdapter(this, list)); mViewPager.addOnPageChangeListener(new OnPageChangeListener() { // 当前选中的是第几个界面 @Override public void onPageSelected(int position) { if (position==imageId.length-1) { btnStart.setVisibility(View.VISIBLE); } else { btnStart.setVisibility(View.GONE); } } // 界面滑动的时候,会不断地回调这个方法 // 第二个参数是当前页面滑过的百分比(0.0到1.0) @Override public void onPageScrolled(int position, float offset, int arg2) { Log.i(TAG, "arg1:" + offset); // 小红点当前滑动的距离 int width = (int) (poitWidth * offset + position * poitWidth); RelativeLayout.LayoutParams layoutParams = (RelativeLayout.LayoutParams) mViewPress.getLayoutParams(); layoutParams.leftMargin = width; mViewPress.setLayoutParams(layoutParams); } @Override public void onPageScrollStateChanged(int arg0) { } }); } }
package com.xspacing.viewpager; import java.util.List; import android.content.Context; import android.support.v4.view.PagerAdapter; import android.view.View; import android.view.ViewGroup; import android.widget.ImageView; public class ViewPgerAdapter extends PagerAdapter { Context mContext; List<ImageView> list; public ViewPgerAdapter(Context context, List<ImageView> list) { this.mContext = context; this.list = list; } // 页数 @Override public int getCount() { return list.size(); } // 复用页卡 @Override public boolean isViewFromObject(View view, Object obj) { return view == obj; } // 销毁页卡 @Override public void destroyItem(ViewGroup container, int position, Object object) { container.removeView(list.get(position)); } // 生成页卡 @Override public Object instantiateItem(ViewGroup container, int position) { View view = list.get(position); container.addView(view); return view; } }
shape文件
<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="oval" > <size android:height="10dp" android:width="10dp" /> <solid android:color="#C3C3C3"/> </shape>
<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="oval" > <size android:height="10dp" android:width="10dp" /> <solid android:color="#44FF0000"/> </shape>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context="com.xspacing.viewpager.MainActivity" > <android.support.v4.view.ViewPager android:id="@+id/main_view_pager" android:layout_width="match_parent" android:layout_height="match_parent" > </android.support.v4.view.ViewPager> <RelativeLayout android:id="@+id/main_relative" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentBottom="true" android:layout_centerHorizontal="true" android:layout_marginBottom="50dp" > <LinearLayout android:id="@+id/main_point" android:layout_width="wrap_content" android:layout_height="wrap_content" android:orientation="horizontal" > </LinearLayout> <ImageView android:id="@+id/main_red_point_press" android:layout_width="wrap_content" android:layout_height="wrap_content" android:background="@drawable/shape_red_point_press" /> </RelativeLayout> <Button android:id="@+id/main_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginBottom="30dp" android:visibility="gone" android:layout_above="@id/main_relative" android:layout_centerHorizontal="true" android:text="开始体验" /> </RelativeLayout>
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持海外IDC网。
【文章出处:美国多ip服务器】