android.support.v4.view.ViewPager#LayoutParams ( )源码实例Demo

/**
 * Get view from position
 *
 * @param container
 * @param position
 * @return
 */
@Override
public Object instantiateItem(ViewGroup container, int position) {
    int itemViewType = getItemViewType(position);
    RecyclerView.ViewHolder holder = mRecycledViewPool.getRecycledView(itemViewType);

    if (holder == null) {
        holder = mAdapter.createViewHolder(container, itemViewType);
    }


    onBindViewHolder((VH) holder, position);
    //itemViews' layoutParam will be reused when there are more than one nested ViewPager in one page,
    //so the attributes of layoutParam such as widthFactor and position will also be reused,
    //while these attributes should be reset to default value during reused.
    //Considering ViewPager.LayoutParams has a few inner attributes which could not be modify outside, we provide a new instance here

    ViewPager.LayoutParams layoutParams = new ViewPager.LayoutParams();
    if (holder.itemView.getLayoutParams() != null) {
        layoutParams.width = holder.itemView.getLayoutParams().width;
        layoutParams.height = holder.itemView.getLayoutParams().height;
    }

    container.addView(holder.itemView, layoutParams);

    return holder;
}
 

private void initImages() {
    mImageViews = new ArrayList<>();

    ViewPager.LayoutParams lp=new ViewPager.LayoutParams();
    lp.gravity= Gravity.LEFT;

    ImageView imageView1 = new ImageView(this);
    imageView1.setImageResource(R.drawable.jay_fantexi);
    imageView1.setScaleType(ImageView.ScaleType.CENTER_CROP);

    ImageView imageView2 = new ImageView(this);
    imageView2.setImageResource(R.drawable.jay_jay);
    imageView2.setScaleType(ImageView.ScaleType.CENTER_CROP);

    ImageView imageView3 = new ImageView(this);
    imageView3.setImageResource(R.drawable.image2);
    imageView3.setScaleType(ImageView.ScaleType.CENTER_CROP);

    ImageView imageView4 = new ImageView(this);
    imageView4.setImageResource(R.drawable.jay_jay);
    imageView4.setScaleType(ImageView.ScaleType.CENTER_CROP);

    ImageView imageView5 = new ImageView(this);
    imageView5.setImageResource(R.drawable.logo);
    imageView5.setScaleType(ImageView.ScaleType.CENTER_CROP);

    imageView1.setLayoutParams(lp);
    imageView2.setLayoutParams(lp);
    imageView3.setLayoutParams(lp);
    imageView4.setLayoutParams(lp);
    imageView5.setLayoutParams(lp);

    mImageViews.add(imageView1);
    mImageViews.add(imageView2);
    mImageViews.add(imageView3);
    mImageViews.add(imageView4);
    mImageViews.add(imageView5);
}
 

/**
 * 装载ScrollerPager
 */
private void addScrollerPager() {
    ViewPager.LayoutParams layoutParams = new ViewPager.LayoutParams();
    layoutParams.width = ViewPager.LayoutParams.MATCH_PARENT;
    layoutParams.height = ViewPager.LayoutParams.MATCH_PARENT;
    mContainer.addView(this, layoutParams);
}
 

@Override
protected void onAttachedToWindow() {
    super.onAttachedToWindow();
    final ViewParent parent = getParent();
    if (!(parent instanceof ViewPager)) {
        throw new IllegalStateException("PagerIndicator must be a direct child of a ViewPager.");
    }
    ((ViewPager.LayoutParams) getLayoutParams()).isDecor = true;
    mParentPager = (ViewPager) parent;
    mParentPager.addOnPageChangeListener(this);
}
 

/**
 * create ViewPager view</br>
 * 
 * @return
 */
private ViewPager createVIewpager() {
    ViewPager viewPager = new ViewPager(getContext());
    ViewPager.LayoutParams params = new ViewPager.LayoutParams();
    params.width = android.support.v4.view.ViewPager.LayoutParams.MATCH_PARENT;
    params.height = BOARD_HEIGHT;
    viewPager.setLayoutParams(params);
    viewPager.setPadding(0, 15, 0, 0);
    return viewPager;
}
 

private void initImgs() {
    mImageViews = new ArrayList<>();
    mStringList=new ArrayList<>();

    ViewPager.LayoutParams lp = new ViewPager.LayoutParams();
    lp.gravity = Gravity.LEFT;

    ImageView imageView1 = new ImageView(this);
    imageView1.setImageResource(R.drawable.jay_fantexi);
    imageView1.setScaleType(ImageView.ScaleType.CENTER_CROP);

    ImageView imageView2 = new ImageView(this);
    imageView2.setImageResource(R.drawable.jay_jay);
    imageView2.setScaleType(ImageView.ScaleType.CENTER_CROP);

    ImageView imageView3 = new ImageView(this);
    imageView3.setImageResource(R.drawable.logo);
    imageView3.setScaleType(ImageView.ScaleType.CENTER_CROP);

    ImageView imageView4 = new ImageView(this);
    imageView4.setImageResource(R.drawable.image2);
    imageView4.setScaleType(ImageView.ScaleType.CENTER_CROP);

    ImageView imageView5 = new ImageView(this);
    imageView5.setImageResource(R.drawable.jay_jay);
    imageView5.setScaleType(ImageView.ScaleType.CENTER_CROP);

    ImageView imageView6 = new ImageView(this);
    imageView6.setImageResource(R.drawable.logo);
    imageView6.setScaleType(ImageView.ScaleType.CENTER_CROP);

    imageView1.setLayoutParams(lp);
    imageView2.setLayoutParams(lp);
    imageView3.setLayoutParams(lp);
    imageView4.setLayoutParams(lp);
    imageView5.setLayoutParams(lp);
    imageView6.setLayoutParams(lp);

    mImageViews.add(imageView1);
    mImageViews.add(imageView2);
    mImageViews.add(imageView3);
    mImageViews.add(imageView4);
    mImageViews.add(imageView5);
    mImageViews.add(imageView6);
    mStringList.add("youngkaaa test 1");
    mStringList.add("hahahahha");
    mStringList.add("yyyyyyyyyyyyyyy");
    mStringList.add("aaaaaaaaaaaaaa");
    mStringList.add("pipipipipipipipipi");
    mStringList.add("kkkkkkkkkkkkkkkkk");

}
 

@Override
protected ViewGroup.LayoutParams generateDefaultLayoutParams() {
    return new ViewPager.LayoutParams();
}
 

public void addView(View child, ViewPager.LayoutParams params) {
    super.addView(wrapChild(child), params);
}
 

public void addView(View child, int index, ViewPager.LayoutParams params) {
    super.addView(wrapChild(child), index, params);
}