androidandroid-recyclerviewpadding
I'm trying to add Padding/Margin Bottom in the last row and Padding/Margin Top in the first row. I can not do it in the item xml as it would affect all of my Children.
I have headers and children in my RecyclerView Adapter so I can not use the
android:padding="4dp"
android:clipToPadding="false"
I need to use it individually on the last first row of each header
To fix the OutOfMemory error, you should do something like this:
BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize = 8;
Bitmap preview_bitmap = BitmapFactory.decodeStream(is, null, options);
This inSampleSize option reduces memory consumption.
Here's a complete method. First it reads image size without decoding the content itself. Then it finds the best inSampleSize value, it should be a power of 2, and finally the image is decoded.
// Decodes image and scales it to reduce memory consumption
private Bitmap decodeFile(File f) {
try {
// Decode image size
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeStream(new FileInputStream(f), null, o);
// The new size we want to scale to
final int REQUIRED_SIZE=70;
// Find the correct scale value. It should be the power of 2.
int scale = 1;
while(o.outWidth / scale / 2 >= REQUIRED_SIZE &&
o.outHeight / scale / 2 >= REQUIRED_SIZE) {
scale *= 2;
}
// Decode with inSampleSize
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize = scale;
return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
} catch (FileNotFoundException e) {}
return null;
}
To help me remember the meaning of padding, I think of a big coat with lots of thick cotton padding. I'm inside my coat, but me and my padded coat are together. We're a unit.
But to remember margin, I think of, "Hey, give me some margin!" It's the empty space between me and you. Don't come inside my comfort zone -- my margin.
To make it more clear, here is a picture of padding and margin in a TextView:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:background="#c5e1b0"
android:textColor="#000000"
android:text="TextView margin only"
android:textSize="20sp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:background="#f6c0c0"
android:textColor="#000000"
android:text="TextView margin only"
android:textSize="20sp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#c5e1b0"
android:padding="10dp"
android:textColor="#000000"
android:text="TextView padding only"
android:textSize="20sp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#f6c0c0"
android:padding="10dp"
android:textColor="#000000"
android:text="TextView padding only"
android:textSize="20sp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:background="#c5e1b0"
android:textColor="#000000"
android:padding="10dp"
android:text="TextView padding and margin"
android:textSize="20sp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="10dp"
android:background="#f6c0c0"
android:textColor="#000000"
android:padding="10dp"
android:text="TextView padding and margin"
android:textSize="20sp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#c5e1b0"
android:textColor="#000000"
android:text="TextView no padding no margin"
android:textSize="20sp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#f6c0c0"
android:textColor="#000000"
android:text="TextView no padding no margin"
android:textSize="20sp" />
</LinearLayout>
Best Answer
This issue is even easier to solve. You can apply necessary padding to the
RecylerViewitself and setclipToPaddingto false, otherwise, the padding will chop off your scrolling area. Here is an exampleSee the padding will add 4dp on all sides including top and bottom. Then the clipToPadding parameter makes sure your child items are not chopped off. Now, add
4dppadding to all sides for your child items, and you are good to go. In total you get 8dp padding on sides and between items.