Start Android
1, what is the relative layout ()Relative layout is the way in which another control is placed, relative to the layout by specifying the relative position between the current control and the sibling control or the parent control, to control the position of the control;
2. Why to use relative layoutThe UI performance of relative layouts is better than the linear layout (too many nesting);
3, relative layout of the common properties
Some of the important attributes that relativelayout uses:
First Class: property value is True or false
Android:layout_centerhrizontal Horizontal Center
Android:layout_centervertical Vertical Center
Android:layout_centerinparent is completely centered relative to the parent element
Android:layout_alignparentbottom snaps to the bottom edge of the parent element
Android:layout_alignparentleft snaps to the left edge of the parent element
Android:layout_alignparentright snaps to the right edge of the parent element
Android:layout_alignparenttop snaps to the top edge of the parent element
android:layout_alignwithparentifmissing if the corresponding sibling element cannot be found, then the parent element is the reference.
Second class: The attribute value must be the reference name of the id "@id/id-name"
Android:layout_below at the bottom of an element
Android:layout_above at the top of an element
Android:layout_toleftof on the left side of an element
Android:layout_torightof on the right side of an element
Android:layout_aligntop aligns the top edge of this element with the top edge of an element
Android:layout_alignleft aligns the left edge of this element with the left edge of an element
Android:layout_alignbottom aligns the bottom edge of this element with the bottom edge of an element
Android:layout_alignright aligns the right edge of this element with the right edge of an element
Class III: Attribute values are specific pixel values, such as 30dip,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 top edge of an element
These properties can be found in Baidu, I went to Baidu downloaded a property Daquan ...
It's too lazy to post here.