Thoughts on Android (14): Relative layout relativelayout

Relative layout relativelayout, inherited from viewgroup. The position of the sub-component of the relative layout is always relative to the sibling component or parent container.

XML attributes supported by Relativelayout:

android:gravity setgravity (int): Set the alignment of the subcomponents in the container

android:ignoregravity setignoregravity (int): Sets which subcomponent is not affected by the gravity Property

Relativelayout has an internal class relativelayout.layoutparams to control how the subcomponents are laid out.

The XML attributes supported by Relativelayout.layoutparams are as follows:

First Class:Property value istrueorfalse
Android:layout_centerhrizontalCenter Horizontally
Android:layout_centerverticalCenter Vertically
Android:layout_centerinparentfully centered relative to parent element
Android:layout_alignparentbottomsnaps to the bottom edge of the parent element
Android:layout_alignparentleftsnaps to the left edge of the parent element
Android:layout_alignparentrightsnaps to the right edge of the parent element
Android:layout_alignparenttopsnaps to the top edge of the parent element
Android:layout_alignwithparentifmissingif the corresponding sibling element cannot be found, then the parent element is the reference.

Class II: The attribute value must beIDthe reference name"@id/id-name”
Android:layout_belowat the bottom of an element
Android:layout_aboveat the top of an element
Android:layout_toleftofon the left side of an element
Android:layout_torightofon the right side of an element

android:layout_aligntop                        Align 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                      Align 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

Android Thoughts (14): Relative layout relativelayout