Androidカスタムビュー描画プレビューセクションでBitmapDrawableレンダリングが正しく行われない

Question

この例では2つのビューがあります。左は私のカスタムビュー、右はImageViewです。 ImageViewがプレビュー画面に正しく描画されるようです。ただし、両方のビューは実行中のデバイスで正しく描画されます。

しかしImageViewのように正しいプレビューを表示したい。私は何を間違えたのですか？

PREVIEW

実行するデバイス

XML

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:app="http://schemas.android.com/apk/res-auto" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:id="@+id/activity_main" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    tools:context="com.apg.mobile.repeatlayout.MainActivity"> 

    <com.my.CustomView 
     android:id="@+id/aa" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_marginTop="10dp" 
     android:background="@color/colorPrimary" 
     app:src="@drawable/samplebg" /> 

    <ImageView 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_marginStart="5dp" 
     android:layout_marginTop="10dp" 
     android:layout_toEndOf="@+id/aa" 
     android:background="@color/colorPrimary" 
     android:src="@drawable/samplebg" /> 

</RelativeLayout> 

のCustomView

public class CustomView extends View { 

    private BitmapDrawable bitmapDrawable; 

    public CustomView(Context context) { 
     super(context); 
    } 

    public CustomView(Context context, @Nullable AttributeSet attrs) { 
     super(context, attrs); 
     readAttribute(context, attrs, 0); 
    } 

    public CustomView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) { 
     super(context, attrs, defStyleAttr); 
     readAttribute(context, attrs, defStyleAttr); 
    } 

    @TargetApi(23) 
    public CustomView(Context context, @Nullable AttributeSet attrs, int defStyleAttr, int defStyleRes) { 
     super(context, attrs, defStyleAttr, defStyleRes); 
     readAttribute(context, attrs, defStyleAttr); 
    } 

    private void readAttribute(Context context, AttributeSet attrs, int defStyleAttr) { 

     TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.CustomView); 
     Drawable drawable = a.getDrawable(R.styleable.CustomView_src); 

     if (drawable == null) 
      throw new NullPointerException("You have to set src first.."); 

     bitmapDrawable = drawableToBitmapDrawable(drawable); 

     a.recycle(); 
    } 

    @Override 
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { 

     int wm, hm; 
     int viewHeightMode = MeasureSpec.getMode(heightMeasureSpec); 
     int viewWidthMode = MeasureSpec.getMode(widthMeasureSpec); 

     Log.d("VIEW WIDTH-MODE", getMode(viewWidthMode)); 
     Log.d("VIEW HEIGHT-MODE", getMode(viewHeightMode)); 

     // 1: find user desired dimension 
     int desiredWidth = measureDesiredSize(widthMeasureSpec, bitmapDrawable.getIntrinsicWidth()); 
     int desiredHeight = measureDesiredSize(heightMeasureSpec, bitmapDrawable.getIntrinsicHeight()); 

     wm = MeasureSpec.makeMeasureSpec(desiredWidth, viewWidthMode); 
     hm = MeasureSpec.makeMeasureSpec(desiredHeight, viewHeightMode); 
     setMeasuredDimension(wm, hm); 
    } 

    @Override 
    protected void onDraw(Canvas canvas) { 

     bitmapDrawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight()); 
     bitmapDrawable.draw(canvas); 
    } 

    private int measureDesiredSize(int measureSpec, int imageSize) { 

     int mode = MeasureSpec.getMode(measureSpec); 
     int size = MeasureSpec.getSize(measureSpec); 

     if (mode == MeasureSpec.EXACTLY) { 
      return size; 
     } else if (mode == MeasureSpec.AT_MOST) { 
      return Math.min(size, imageSize); 
     } else { 
      return imageSize; 
     } 
    } 

    public BitmapDrawable drawableToBitmapDrawable(Drawable drawable) { 

     if (drawable instanceof BitmapDrawable) { 

      return (BitmapDrawable) drawable; 
     } else if (drawable.getIntrinsicWidth() <= 0 || drawable.getIntrinsicHeight() <= 0) { 

      // Single color bitmap will be created of 1x1 pixel 
      Bitmap bitmap = Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888); 
      return new BitmapDrawable(getResources(), bitmap); 
     } else { 

      Bitmap bitmap = Bitmap.createBitmap(
        drawable.getIntrinsicWidth(), 
        drawable.getIntrinsicHeight(), 
        Bitmap.Config.ARGB_8888); 
      return new BitmapDrawable(getResources(), bitmap); 
     } 
    } 


    private String getMode(int mode) { 

     if (MeasureSpec.AT_MOST == mode) { 
      return "AT_MOST"; 
     } else if (MeasureSpec.EXACTLY == mode) { 
      return "EXACTLY"; 
     } else { 
      return "UNSPECIFIED"; 
     } 
    } 
} 

属性

<?xml version="1.0" encoding="utf-8"?> 
<resources> 

    <declare-styleable name="CustomView"> 
     <attr name="src" format="reference" />  
    </declare-styleable> 

</resources> 

リソース

Sample drawable描画可能なフォルダに入れてください。

Answer 1

私は、幅と高さのフォームonSizeChangedを使用して私の問題を解決することができます。

@Override 
    protected void onSizeChanged(int xNew, int yNew, int xOld, int yOld){ 
     super.onSizeChanged(xNew, yNew, xOld, yOld); 

     mViewWidth = xNew; 
     mViewHeight = yNew; 
    } 

    @Override 
    protected void onDraw(Canvas canvas) { 

     bitmapDrawable.setBounds(0, 0, mViewWidth, mViewHeight); 
     bitmapDrawable.draw(canvas); 
    }