Android仿微信朋友圈点击加号添加图片功能

<?xml version="1.0" encoding="utf-8"?>
<linearlayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_margintop="40dp"
android:orientation="vertical" >
 
<com.sw.demo.widget.ninephotoview
  android:id="@+id/photoview"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  app:ninephoto_hspace="10dp"
  app:ninephoto_vspace="10dp"
  app:rainbowbar_color="@android:color/holo_blue_bright" >
 
</com.sw.demo.widget.ninephotoview>

public class ninephotoview extends viewgroup {
 
public static final int max_photo_number = 9;
 
private int[] constimageids = { r.drawable.girl_0, r.drawable.girl_1,
   r.drawable.girl_2, r.drawable.girl_3, r.drawable.girl_4,
   r.drawable.girl_5, r.drawable.girl_6, r.drawable.girl_7,
   r.drawable.girl_8 };
 
// horizontal space among children views
int hspace = utils.dptopx(10, getresources());
// vertical space among children views
int vspace = utils.dptopx(10, getresources());
 
// every child view width and height.
int childwidth = 0;
int childheight = 0;
 
// store images res id
arraylist<integer> mimageresarraylist = new arraylist<integer>(9);
private view addphotoview;
 
public ninephotoview(context context) {
 super(context);
}
 
public ninephotoview(context context, attributeset attrs) {
 this(context, attrs, 0);
}
 
public ninephotoview(context context, attributeset attrs, int defstyle) {
 super(context, attrs, defstyle);
 
 typedarray t = context.obtainstyledattributes(attrs,
     r.styleable.ninephotoview, 0, 0);
 hspace = t.getdimensionpixelsize(
     r.styleable.ninephotoview_ninephoto_hspace, hspace);
 vspace = t.getdimensionpixelsize(
     r.styleable.ninephotoview_ninephoto_vspace, vspace);
 t.recycle();
 
 addphotoview = new view(context);
 addview(addphotoview);
 mimageresarraylist.add(new integer());
}

@override
protected void onmeasure(int widthmeasurespec, int heightmeasurespec) {
 int rw = measurespec.getsize(widthmeasurespec);
 int rh = measurespec.getsize(heightmeasurespec);
 
 childwidth = (rw - 2 * hspace) / 3;
 childheight = childwidth;
 
 int childcount = this.getchildcount();
 for (int i = 0; i < childcount; i++) {
   view child = this.getchildat(i);
   //this.measurechild(child, widthmeasurespec, heightmeasurespec);
 
   layoutparams lparams = (layoutparams) child.getlayoutparams();
   lparams.left = (i % 3) * (childwidth + hspace);
   lparams.top = (i / 3) * (childwidth + vspace);
 }
 
 int vw = rw;
 int vh = rh;
 if (childcount < 3) {
   vw = childcount * (childwidth + hspace);
 }
 vh = ((childcount + 3) / 3) * (childwidth + vspace);
 setmeasureddimension(vw, vh);
}

@override
protected void onlayout(boolean arg0, int arg1, int arg2, int arg3, int arg4) {
 int childcount = this.getchildcount();
 for (int i = 0; i < childcount; i++) {
   view child = this.getchildat(i);
   layoutparams lparams = (layoutparams) child.getlayoutparams();
   child.layout(lparams.left, lparams.top, lparams.left + childwidth,
       lparams.top + childheight);
 
   if (i == mimageresarraylist.size() - 1 && mimageresarraylist.size() != max_photo_number) {
     child.setbackgroundresource(r.drawable.add_photo);
     child.setonclicklistener(new view.onclicklistener() {
 
       @override
       public void onclick(view arg0) {
         addphotobtnclick();
       }
     });
   }else {
     child.setbackgroundresource(constimageids[i]);
     child.setonclicklistener(null);
   }
 }
}
 
public void addphoto() {
 if (mimageresarraylist.size() < max_photo_number) {
   view newchild = new view(getcontext());
   addview(newchild);
   mimageresarraylist.add(new integer());
   requestlayout();
   invalidate();
 }
}
 
public void addphotobtnclick() {
 final charsequence[] items = { "take photo", "photo from gallery" };
 
 alertdialog.builder builder = new alertdialog.builder(getcontext());
 builder.setitems(items, new dialoginterface.onclicklistener() {
 
   @override
   public void onclick(dialoginterface arg0, int arg1) {
     addphoto();
   }
 
 });
 builder.show();
}