int newHeight = 150;
            int newWidth = 150; 
            holder.iv_arrow.requestLayout();
            holder.iv_arrow.getLayoutParams().height = newHeight;
            holder.iv_arrow.getLayoutParams().width = newWidth;
            holder.iv_arrow.setScaleType(ImageView.ScaleType.FIT_XY);
            holder.iv_arrow.setImageResource(R.drawable.video_menu);

为了以编程方式设置ImageView和Height，你可以这样做

            //Makesure you calculate the density pixel and multiply it with the size of width/height
            float dpCalculation = getResources().getDisplayMetrics().density;
            your_imageview.getLayoutParams().width = (int) (150 * dpCalculation);

            //Set ScaleType according to your choice...
            your_imageview.setScaleType(ImageView.ScaleType.CENTER_CROP);

在需要以编程方式设置小部件大小的场景中，请确保遵守以下规则。

为要添加该视图的布局设置LayoutParam。在我的情况下，我添加到TableRow，所以我必须做TableRow。LayoutParams 遵循以下代码

final float scale = getResources().getDisplayMetrics().density; int dpWidthInPx = (int) (17 * scale); int dpHeightInPx = (int) (17 * scale);

TableRow。LayoutParams deletelayoutParams = new table。LayoutParams (dpWidthInPx dpHeightInPx); button.setLayoutParams (deletelayoutParams); tableRow。addView(按钮,1);

的形象。setLayoutParams(新ViewGroup。LayoutParams(宽度、高度));

例子:

image.setLayoutParams(new ViewGroup.LayoutParams(150, 150));

科特林

val density = Resources.getSystem().displayMetrics.density
view.layoutParams.height = 20 * density.toInt()

动态设置按钮的最佳和最简单的方法是

 Button index=new Button(this);
 int height = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 45, getResources().getDisplayMetrics());             
 int width = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 42, getResources().getDisplayMetrics());

上面的高度和宽度以像素为单位px。45是dp的高42是dp的宽。

 index.setLayoutParams(new <Parent>.LayoutParams(width, height));

例如，如果你把你的按钮放在一个tableerow中在一个tableelayout中，你应该把它作为TableRow。LayoutParams

 index.setLayoutParams(new TableRow.LayoutParams(width, height));