ImageView setImageURI圖片不改變\NetWorkImageView 不顯示的問題

ImageView

問題描述：圖片文件已改變，第二次調用ImageView.setImageURI時無法更新圖片

分析：setImageURI方法中對uri進行了緩存，由於第一次加載過了該uri的資源，即使該文件內容改變了，判斷中仍然會使用之前加載的。

    public void setImageURI(Uri uri) {
        if (mResource != 0 ||
                (mUri != uri &&
                 (uri == null || mUri == null || !uri.equals(mUri)))) {
            updateDrawable(null);
            mResource = 0;
            mUri = uri;

            final int oldWidth = mDrawableWidth;
            final int oldHeight = mDrawableHeight;

            resolveUri();

            if (oldWidth != mDrawableWidth || oldHeight != mDrawableHeight) {
                requestLayout();
            }
            invalidate();
        }
    }

 

解決辦法：

1、使用不同的文件名（不同的URI）

2、使用setImageBitmap的方式代替

Bitmap bmp;
try {
    bmp = MediaStore.Images.Media.getBitmap(context.getContentResolver(), Uri.fromFile(file));
    iv.setImageBitmap(bmp); 
} catch (FileNotFoundException e) {
} catch (IOException e) {
}

NetWorkImageView

//Copy the code from Volley's NetworkImageView and change onLayout as below.

@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
    super.onLayout(changed, left, top, right, bottom);
    if (!TextUtils.isEmpty(mUrl)) {
        loadImageIfNecessary(true);
    }else{
        if (mImageContainer != null) {
            mImageContainer.cancelRequest();
            mImageContainer = null;
        }
    }
}

//Change the other ImageView image setters, for example...
@Override
public void setImageDrawable(Drawable drawable) {
    mUrl = null;
    super.setImageDrawable(drawable);
}

@Override
public void setImageURI(Uri uri) {
    mUrl = null;
    super.setImageURI(uri);
}    

 

Reference:http://kalkanotel.com/networkimageview-set-image-from-file-i225690.htm