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 viewsint hSpace = Utils.dpToPx(10, getResources());// vertical space among children viewsint vSpace = Utils.dpToPx(10, getResources()); // every child view width and height.int childWidth = 0;int childHeight = 0; // store images res idArrayList<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());}

@Overrideprotected 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);}

@Overrideprotected 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();}