使用ViewPager浏览位图图像

Question

我正在尝试创建一个可以浏览照片的应用程序。我目前已将图像保存为位图。如何使用ViewPager浏览图像？(最好没有Picasso或Glide(

Answer 1

你说你有位图，把它存储在arraylist中。首先，为ViewPager制作一个适配器。

public class AdapterPagerImageSlider extends PagerAdapter {
private ArrayList<Bitmap> bitmaps;
private Context context;
private LayoutInflater layoutInflater;
public AdapterPagerImageSlider(Context context, ArrayList<Bitmap> bitmaps) {
this.context = context;
this.bitmaps= bitmaps;
}
@Override
public Object instantiateItem(ViewGroup container, int position) {
layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view = layoutInflater.inflate(R.layout.inflater_imageslider, container, false);
ImageView imageView = view.findViewById(R.id.image);
imageView.setImageBitmap(bitmaps.get(position)); //this set image from bitmap
container.addView(view);
return view;
}
@Override
public int getCount() {
return bitmaps.size();
}
@Override
public void destroyItem(ViewGroup container, int position, Object object) {
container.removeView((LinearLayout) object);
}
@Override
public boolean isViewFromObject(@NonNull View view, @NonNull Object o) {
return (view == o);
}
}

然后，制作一个布局并将其命名为充气器_图像滑块

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageView
android:id="@+id/image"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>

最后，声明该适配器并将其设置为ViewPager。

ArrayList<Bitmap> bitmaps = new ArrayList<>();
//code of storing your bitmaps to arraylist here : bitmaps.add(yourbitmap);
ViewPager vp = findViewById(R.id.vp);
AdapterPagerImageSlider adapter = new AdapterPagerImageSlider(MainActivity.this, bitmaps);
vp.setAdapter(adapter);

希望能有所帮助。