Android how to make Gallery auto scroll to first item
http://www.drovik.com/ 2013-10-18 22:46:28 来源：www.drovik.com 点击：
private void alignGalleryToLeft(Gallery gallery) {
WindowManager manager = (WindowManager) getSystemService(Context.WINDOW_SERVICE); int galleryWidth = manager.getDefaultDisplay().getWidth(); // We are taking the item widths and spacing from a dimension resource // because: // 1. No way to get spacing at runtime (no accessor in the Gallery // class) // 2. There might not yet be any item view created when we are calling // this // function int itemWidth = getsize(105); int spacing = getsize(10); // The offset is how much we will pull the gallery to the left in order // to simulate left alignment of the first item final int offset; if (galleryWidth <= itemWidth) { offset = galleryWidth / 2 - itemWidth / 2 - spacing; } else { offset = galleryWidth - itemWidth - 2 * spacing; } // Now update the layout parameters of the gallery in order to set the // left margin MarginLayoutParams mlp = (MarginLayoutParams) gallery.getLayoutParams(); mlp.setMargins(-offset, mlp.topMargin, mlp.rightMargin, mlp.bottomMargin); }getsize() is a method:
public int getsize(int sizeInDip) { DisplayMetrics metrics = new DisplayMetrics(); metrics = getResources().getDisplayMetrics(); return (int) ((sizeInDip * metrics.density) + 0.5); }pass your value in DPI into this method.
Hope,it will work for you.
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