Android layout attributes

RelativeLayoutImportant attributes used:

 

Class 1: the property value is true or false.
Android: layout_centerHrizontal horizontal center
Android: layout_centerVertical vertical center
Android: layout_centerInparent is completely centered over the parent Element
Android: layout_alignParentBottom: attach the lower edge of the parent Element
Android: layout_alignParentLeft: Stick the left edge of the parent Element
Android: layout_alignParentRight: attaches the right edge of the parent element.
Android: layout_alignParentTop: top the parent Element
Android: layout_alignWithParentIfMissing

Class 2: the property value must be the reference name "@ id/id-name" of the id"
Android: layout_below is under an element
Android: layout_abve is above an element.
Android: layout_toLeftOf on the left of an element
Android: layout_toRightOf on the right of an element

Android: layout_alignTop: Align the top edge of an element with the top edge of an element.
Android: layout_alignLeft: Align the left edge of an element with the left edge of an element.
Android: layout_alignBottom: the bottom edge of the current element is aligned with the bottom edge of an element.
Android: layout_alignRight: the right edge of an element is aligned with the right edge of an element.

Category 3: attribute values are specific pixel values, such as 30dip and 40px.
Android: layout_marginBottom distance from the bottom edge of an element
Android: layout_marginLeft distance from the left edge of an element
Android: layout_marginRight distance from the right edge of an element
Android: layout_marginTop distance from the edge of an element

Android: hint of EditText 

Prompt information in the input box when EditText is set to null.

Android: gravity
Android: gravity attribute is a limitation on the view content. for example, text on a button. you can set the text to the left and right of the view. take the button as an example. For android: gravity = "right", the text on the button is right-aligned.

Android: layout_gravity 
Android: layout_gravity is used to set the location of the view relative to the parent view. for example, if a button is in linearlayout, you can set it by placing it on the left or right. take the button as an example. For android: layout_gravity = "right", the button is right-aligned.

Android: layout_alignParentRight 
Align the right end of the current control with the right end of the parent control. The attribute value can only be true or false. The default value is false.

Android: scaleType: 
Android: scaleType controls how images are resized/moved to match the size of ImageView. ImageView. ScaleType/android: the differences between scaleType values:

CENTER/center is centered according to the original size of the image. When the length/width of the image exceeds the length/width of the View, the CENTER part of the captured image is displayed.

CENTER_CROP/centerCrop scales up the image size in the center, so that the image length (width) is equal to or greater than the View length (width)

CENTER_INSIDE/centerInside shows the entire content of the image in the center. The image length/width is equal to or less than the View length/width by proportional reduction or the original size.

FIT_CENTER/fitCenter scales up/down the image proportionally to the width of the View and center the image.

FIT_END/fitEnd: scales up or down an image to the width of the View, which is displayed in the lower part of the View.

FIT_START/fitStart scales up/down an image proportionally to the width of the View.

FIT_XY/fitXY increase or decrease the image size proportionally to the View size.

MATRIX/matrix is drawn using a MATRIX to dynamically zoom in and zoom in images.

** Note that the names of images in the Drawable folder cannot be capitalized.