我有一个GridView。GridView的数据是来自服务器的请求。
下面是GridView中的项目布局:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/analysis_micon_bg"
android:gravity="center_horizontal"
android:orientation="vertical"
android:paddingBottom="@dimen/half_activity_vertical_margin"
android:paddingLeft="@dimen/half_activity_horizontal_margin"
android:paddingRight="@dimen/half_activity_horizontal_margin"
android:paddingTop="@dimen/half_activity_vertical_margin" >
<ImageView
android:id="@+id/ranking_prod_pic"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
android:contentDescription="@string/app_name"
android:scaleType="centerCrop" />
<TextView
android:id="@+id/ranking_rank_num"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="@+id/ranking_prod_num"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<TextView
android:id="@+id/ranking_prod_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
我从服务器请求数据，获取图像url和加载图像到位图
public static Bitmap loadBitmapFromInputStream(InputStream is) {
return BitmapFactory.decodeStream(is);
}
public static Bitmap loadBitmapFromHttpUrl(String url) {
try {
return loadBitmapFromInputStream((InputStream) (new URL(url).getContent()));
} catch (Exception e) {
Log.e(TAG, e.getMessage());
return null;
}
}
适配器中有getView(int position, View convertView, ViewGroup parent)方法的代码
Bitmap bitmap = BitmapUtil.loadBitmapFromHttpUrl(product.getHttpUrl());
prodImg.setImageBitmap(bitmap);
图像大小为210*210。我在Nexus 4上运行我的应用程序。图像填充ImageView的宽度，但ImageView的高度没有缩放。ImageView不显示整个图像。
我怎么解决这个问题?
我曾经遇到过类似的问题。我通过制作一个自定义ImageView解决了这个问题。
public class CustomImageView extends ImageView
然后重写imageview的onMeasure方法。我相信我做过这样的事情:
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
try {
Drawable drawable = getDrawable();
if (drawable == null) {
setMeasuredDimension(0, 0);
} else {
float imageSideRatio = (float)drawable.getIntrinsicWidth() / (float)drawable.getIntrinsicHeight();
float viewSideRatio = (float)MeasureSpec.getSize(widthMeasureSpec) / (float)MeasureSpec.getSize(heightMeasureSpec);
if (imageSideRatio >= viewSideRatio) {
// Image is wider than the display (ratio)
int width = MeasureSpec.getSize(widthMeasureSpec);
int height = (int)(width / imageSideRatio);
setMeasuredDimension(width, height);
} else {
// Image is taller than the display (ratio)
int height = MeasureSpec.getSize(heightMeasureSpec);
int width = (int)(height * imageSideRatio);
setMeasuredDimension(width, height);
}
}
} catch (Exception e) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
这将拉伸图像以适应屏幕，同时保持纵横比。
我曾经遇到过类似的问题。我通过制作一个自定义ImageView解决了这个问题。
public class CustomImageView extends ImageView
然后重写imageview的onMeasure方法。我相信我做过这样的事情:
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
try {
Drawable drawable = getDrawable();
if (drawable == null) {
setMeasuredDimension(0, 0);
} else {
float imageSideRatio = (float)drawable.getIntrinsicWidth() / (float)drawable.getIntrinsicHeight();
float viewSideRatio = (float)MeasureSpec.getSize(widthMeasureSpec) / (float)MeasureSpec.getSize(heightMeasureSpec);
if (imageSideRatio >= viewSideRatio) {
// Image is wider than the display (ratio)
int width = MeasureSpec.getSize(widthMeasureSpec);
int height = (int)(width / imageSideRatio);
setMeasuredDimension(width, height);
} else {
// Image is taller than the display (ratio)
int height = MeasureSpec.getSize(heightMeasureSpec);
int width = (int)(height * imageSideRatio);
setMeasuredDimension(width, height);
}
}
} catch (Exception e) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
这将拉伸图像以适应屏幕，同时保持纵横比。
不使用任何自定义类或库:
<ImageView
android:id="@id/img"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
android:scaleType="fitCenter" />
scaleType="fitCenter"(省略时默认值)
将使它的宽度作为父允许和上升/下降规模，需要保持纵横比。
scaleType = centerInside”
如果SRC的固有宽度小于父宽度，则将图像水平居中
如果SRC的固有宽度大于父宽，将使其宽到父宽所允许的范围，并降低比例保持纵横比。
不管你使用android:src还是ImageView。setImage*方法，键可能是adjustViewBounds。
