Android 引导页的代码 _android

君不见长松卧壑困风霜，时来屹立扶明堂。这篇文章主要讲述Android 引导页的代码相关的知识，希望能为你提供帮助。
【Android 引导页的代码】布局代码

< android.support.v4.view.ViewPager android:id=" @+id/viewpage" android:layout_width=" match_parent" android:layout_height=" match_parent" /> < !--android:background=" @drawable/btnselector" --> < Button android:id=" @+id/btnty" android:layout_width=" wrap_content" android:layout_height=" wrap_content" android:layout_alignParentBottom=" true" android:layout_centerHorizontal=" true" android:layout_marginBottom=" 100dp" android:background=" @drawable/btnselector" android:paddingLeft=" 30dp" android:paddingRight=" 30dp" android:visibility=" gone" android:text=" 立即体验" android:textColor=" @drawable/textselector" android:textSize=" 20sp" /> < RelativeLayout android:layout_width=" wrap_content" android:layout_height=" wrap_content" android:layout_alignParentBottom=" true" android:layout_centerHorizontal=" true" android:layout_marginBottom=" 80dp" > < LinearLayout android:id=" @+id/linearpointgroup" android:layout_width=" wrap_content" android:layout_height=" wrap_content" android:orientation=" horizontal" /> < ImageView android:id=" @+id/ivredpoint" android:background=" @drawable/pointred" android:layout_width=" 10dp" android:layout_height=" 10dp" /> < /RelativeLayout>

后台代码
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewTreeObserver;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import java.util.ArrayList;
import java.util.List;
public class GuideActivity extends Activity {

List< ImageView> imageViews; ViewPager vpage; LinearLayout linearLayout; ImageView imagepoint; int leftmax = 0; Button btnty;

int pointwidth=0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_guide);
vpage = (ViewPager) findViewById(R.id.viewpage);
linearLayout = (LinearLayout) findViewById(R.id.linearpointgroup);
imagepoint = (ImageView) findViewById(R.id.ivredpoint);
//10为默认点的布局宽度
pointwidth=DensityUtil.diptopx(GuideActivity.this,10);
btnty = (Button) findViewById(R.id.btnty);
int[] intimage = new int[]{R.drawable.guide1, R.drawable.guide2, R.drawable.guide3};
imageViews = new ArrayList< > ();
for (int ii = 0; ii < intimage.length; ii++) {
ImageView imageView = new ImageView(GuideActivity.this);
imageView.setBackgroundResource(intimage[ii]);
imageViews.add(imageView);
//创建点

ImageView point = new ImageView(GuideActivity.this); point.setBackgroundResource(R.drawable.point); //此处单位是像素需要做大小手机的适配调用转换成像素的方法 LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(pointwidth, pointwidth); if (ii != 0) { params.leftMargin = pointwidth; } point.setLayoutParams(params); linearLayout.addView(point); } vpage.setAdapter(new pagetadapter()); Button btn = (Button) findViewById(R.id.btnty); btn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { //设置缓存进入过主界面 CacheParam.setkey(GuideActivity.this, " EnterMain" , true); Intent intent = new Intent(GuideActivity.this, LogInActivity.class); startActivity(intent); finish(); } }); imagepoint.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() { @Override public void onGlobalLayout() { //执行一次即可所以先移除 imagepoint.getViewTreeObserver().removeGlobalOnLayoutListener(this); //间距 = 第一个点距离左边的距离-第0个点距离左边的距离 leftmax = linearLayout.getChildAt(1).getLeft() - linearLayout.getChildAt(0).getLeft(); } }); vpage.setOnPageChangeListener(new MyPageChange()); }class MyPageChange implements ViewPager.OnPageChangeListener { //当也没滑动的时候调用 /* * 当前滑动页面的位置 * 页面滑动的百分比 * 滑动的像素*/ @Override public void onPageScrolled(int position, float positionoffset, int positionoffsetpixels) {

//两点间滑动距离对应的坐标=原来的起始位置+两点间移动的距离
int leftmargin = (int) (position * leftmax + (positionoffset * leftmax));

RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams) imagepoint.getLayoutParams(); params.leftMargin = leftmargin; imagepoint.setLayoutParams(params); }/** * 当页面选中的时候调用这个方法 * 被选中页面的位置 */ @Override public void onPageSelected(int position) { //最后一个页面 if (position == imageViews.size() - 1) { btnty.setVisibility(View.VISIBLE); } else//其他页面 { btnty.setVisibility(View.GONE); } }/** * 当页面滑动状态变化的时候 */ @Override public void onPageScrollStateChanged(int i) {} }class pagetadapter extends PagerAdapter {@Override public int getCount() { return imageViews.size(); }@Override public Object instantiateItem(@NonNull ViewGroup container, int position) { ImageView imageView = imageViews.get(position); container.addView(imageView); return imageView; }@Override public boolean isViewFromObject(@NonNull View view, @NonNull Object o) { return view == o; }@Override public void destroyItem(@NonNull ViewGroup container, int position, @NonNull Object object) {

// super.destroyItem(container, position, object);
container.removeView((View) object);
}

}

}
import android.content.Context;
public class DensityUtil {
/
根据手机的分辨率从dip的单位转为px 像素/
public static int diptopx(Context context,float dpvalue)
{
final float scale=context.getResources().getDisplayMetrics().density;
return (int)(dpvaluescale+0.5f);
}
/
根据手机的分辨率从px的单位转为dip
* */
public static int pxtodip(Context context,float pxvalue)
{
final float scale=context.getResources().getDisplayMetrics().density;
return (int)(pxvalue/scale+0.5f);
}
}