Android Custom ViewGroup Landscape Layout (1) _android

Recently learning to customize ViewGroup, my goal is to make a ListView that you want to scroll, use adapter to populate the data, and use Adapter.notifydatasetchanged () to update the data.

But eat not a fat one (I eat like this but a few years of accumulation of ~ ~ ~ ~ ~ ~ ~ ~ ~), we step by step, this note first write a horizontal layout.

Code:

Package com.example.libingyuan.horizontallistview.ScrollViewGroup;
Import Android.content.Context;
Import Android.util.AttributeSet;
Import Android.view.View;

Import Android.view.ViewGroup; /** * Custom ViewGroup * Very simple horizontal layout, all the child view are arranged horizontally, not scrollable/public class Scrollviewgroup extends viewgroup{public scrollv
  Iewgroup {This (context,null);
  Public Scrollviewgroup (context, AttributeSet attrs) {This (context, attrs,0); Scrollviewgroup (context, AttributeSet attrs, int defstyleattr) {Super (context, Attrs, Defstyleatt
  R); @Override protected void onmeasure (int widthmeasurespec, int heightmeasurespec) {//Reset width High this.setmeasured
  Dimension (Measurewidth (Widthmeasurespec,heightmeasurespec), Measureheight (Widthmeasurespec,heightmeasurespec)); /** * Measuring width */private int measurewidth (int widthmeasurespec, int heightmeasurespec) {//width int Sizew
   Idth = Measurespec.getsize (Widthmeasurespec); width of type int modewidth = Measurespec.getmode (Widthmeasurespec);
    The width of the parent control (wrap_content) int width = 0;

    Number of child view int childcount = Getchildcount ();
      Re-measure the width of the child view, as well as the maximum height for (int i = 0; i < ChildCount; i++) {//Get child view view children = Getchildat (i);
      Measure the view, no matter what mode, this sentence must have otherwise the interface does not show the view (a blank) measurechild (Child, Widthmeasurespec, Heightmeasurespec);
      Get the margin marginlayoutparams LP = (marginlayoutparams) child.getlayoutparams () of the child view;
      Get the width int childwidth = child.getmeasuredwidth () + Lp.leftmargin + lp.rightmargin;
    width added = childwidth; //Back to width return modewidth = = measurespec.exactly?
  Sizewidth:width; /** * Measuring Height * * private int measureheight (int widthmeasurespec, int heightmeasurespec) {//height int Sizeh
    eight = Measurespec.getsize (HEIGHTMEASURESPEC);
    The height of the pattern int modeheight = Measurespec.getmode (Heightmeasurespec); The height of the parent control (wrap_content) int height =0;

    Number of child view int childcount = Getchildcount ();
      Re-measure the width of the child view, and the maximum height for (int i = 0; i < ChildCount; i++) {//Get the child view view children = Getchildat (i);
      Measure Measurechild (Child, Widthmeasurespec, Heightmeasurespec);
      Get margin Marginlayoutparams LP = (marginlayoutparams) child.getlayoutparams ();
      Get a height of int childheight = Child.getmeasuredheight () + Lp.topmargin + lp.bottommargin;
    Cumulative height = childheight;
    //ask for average height = height/childcount; Back to height return modeheight = = measurespec.exactly?
  Sizeheight:height;
    @Override protected void OnLayout (Boolean changed, int l, int t, int r, int b) {int childleft=0;//Zi view to the left of the distance
    int childwidth;//View width int height=getheight ();
    int Childcount=getchildcount ();
      for (int i = 0; i < ChildCount i++) {View child=getchildat (i);
      Marginlayoutparams lp= (Marginlayoutparams) child.getlayoutparams (); Childwidth=Child.getmeasuredwidth () +lp.leftmargin+lp.rightmargin;
      The most important word child.layout (childleft,0,childleft+childwidth,height);
    Childleft+=childwidth; } @Override Public Layoutparams generatelayoutparams (AttributeSet attrs) {return new Marginlayoutparams (getc
  Ontext (), attrs);

 }
}

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