以下是我的代码。我正在尝试从我的SD卡中检索图像到gridview。我的代码有问题。我无法弄清楚如何将图像设置到我的imageview。我得到错误“ImageView中的方法setImageResource(int)不适用于我的ImageAdapter中的参数(String)”
public class GridViewActivity extends Activity {
private String[] mFileStrings;
private File[] listFile;
GridView grid;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Set title for the GridView
setTitle("GridView");
setContentView(R.layout.grid_view);
File file = new File(Environment.getExternalStorageDirectory()
+ File.separator + "Tutorial");
if (file.isDirectory()) {
listFile = file.listFiles();
mFileStrings = new String[listFile.length];
for (int i = 0; i < listFile.length; i++) {
mFileStrings[i] = listFile[i].getAbsolutePath();
}
}
grid = (GridView) findViewById(R.id.gridview);
grid.setAdapter(new ImageAdapter(this, mFileStrings));
}
ImageAdapter
public class ImageAdapter extends BaseAdapter {
private Context mContext;
private String[] data;
public ImageAdapter(Context c, String[] d) {
mContext = c;
data=d;
}
public int getCount() {
return data.length;
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}
// Create a new ImageView for each item referenced by the Adapter
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView;
if (convertView == null) { // If it's not recycled, initialize some attributes
imageView = new ImageView(mContext);
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
} else {
imageView = (ImageView) convertView;
}
imageView.setImageResource(data[position]); //The method setImageResource(int) in the type ImageView is not applicable for the arguments (String)
return imageView;
}
}
我的编辑
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView;
if (convertView == null) {
imageView = new ImageView(mContext);
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
} else {
imageView = (ImageView) convertView;
}
File imgFile = new File("" + data[position]);
Bitmap myBitmap = BitmapFactory.decodeFile(imgFile.getAbsolutePath());
imageView.setImageBitmap(myBitmap);
return imageView;
}
LOGCAT:
04-12 14:18:59.811: E/AndroidRuntime(27379): FATAL EXCEPTION: main
04-12 14:18:59.811: E/AndroidRuntime(27379): java.lang.OutOfMemoryError
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.graphics.BitmapFactory.nativeDecodeStream(Native Method)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.graphics.BitmapFactory.decodeStream(BitmapFactory.java:587)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.graphics.BitmapFactory.decodeFile(BitmapFactory.java:389)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.graphics.BitmapFactory.decodeFile(BitmapFactory.java:418)
04-12 14:18:59.811: E/AndroidRuntime(27379): at com.androidbegin.gridview.ImageAdapter.getView(ImageAdapter.java:46)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.widget.AbsListView.obtainView(AbsListView.java:2201)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.widget.GridView.onMeasure(GridView.java:1026)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.view.View.measure(View.java:12892)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4698)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.view.View.measure(View.java:12892)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.widget.LinearLayout.measureVertical(LinearLayout.java:812)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.widget.LinearLayout.onMeasure(LinearLayout.java:553)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.view.View.measure(View.java:12892)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4698)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
04-12 14:18:59.811: E/AndroidRuntime(27379): at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2265)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.view.View.measure(View.java:12892)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1624)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2628)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.os.Handler.dispatchMessage(Handler.java:99)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.os.Looper.loop(Looper.java:137)
04-12 14:18:59.811: E/AndroidRuntime(27379): at android.app.ActivityThread.main(ActivityThread.java:4507)
04-12 14:18:59.811: E/AndroidRuntime(27379): at java.lang.reflect.Method.invokeNative(Native Method)
04-12 14:18:59.811: E/AndroidRuntime(27379): at java.lang.reflect.Method.invoke(Method.java:511)
04-12 14:18:59.811: E/AndroidRuntime(27379): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:980)
04-12 14:18:59.811: E/AndroidRuntime(27379): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:747)
04-12 14:18:59.811: E/AndroidRuntime(27379): at dalvik.system.NativeStart.main(Native Method)
答案 0 :(得分:2)
您正在设置imageView.setImageResource(data [position]),其中data是字符串数组。 您需要将文件路径解码为位图,然后将其设置为您的imageview。
在getView()
File imgFile = new File(""+data[position]);
Bitmap myBitmap = BitmapFactory.decodeFile(imgFile.getAbsolutePath());
ImageView myImage = (ImageView) findViewById(R.id.imageviewTest);
myImage.setImageBitmap(myBitmap);
编辑:
您还可以使用LazyList或Universal Image Loader来显示SD卡中的图像。 What's LazyList?。 Lazy List缩小以减少内存消耗。 Universal Image Loader的工作原理与LazyList相同,但它有更多的配置选项。
https://github.com/thest1/LazyList
https://github.com/nostra13/Android-Universal-Image-Loader
//decodes image and scales it to reduce memory consumption
private Bitmap decodeFile(File f){
try {
//decode image size
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
BitmapFactory.decodeStream(new FileInputStream(f),null,o);
//Find the correct scale value. It should be the power of 2.
final int REQUIRED_SIZE=70;
int width_tmp=o.outWidth, height_tmp=o.outHeight;
int scale=1;
while(true){
if(width_tmp/2<REQUIRED_SIZE || height_tmp/2<REQUIRED_SIZE)
break;
width_tmp/=2;
height_tmp/=2;
scale*=2;
}
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize=scale;
return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
} catch (FileNotFoundException e) {}
return null;
}
如果位图太大,则需要缩放它们,然后在imageview中显示相同的位图。此外,您应该使用视图支架来实现平滑滚动和性能。您应该在不使用时回收位图。 gridview中的可见视图不会被回收。您可以使用LazyList或Universal Image Loader。
http://developer.android.com/training/improving-layouts/smooth-scrolling.html
http://www.youtube.com/watch?v=wDBM6wVEO70。谈话是关于观看者和列表视图的表现。同样适用于gridview。
http://developer.android.com/training/displaying-bitmaps/load-bitmap.html。有效加载位图。
如果遇到内存泄漏,请使用MAT Analyzer查找并修复问题。 http://www.youtube.com/watch?v=_CruQY55HOk。
答案 1 :(得分:0)
您必须在适配器中执行此操作
File f = new File("/mnt/sdcard/photo.jpg");
ImageView mImgView1 = (ImageView)findViewById(R.id.imageView);
Bitmap bmp = BitmapFactory.decodeFile(f.getAbsolutePath());
mImgView1.setImageBitmap(bmp);
在这里你必须做File f = new File(""+data[position]);
已修改:您将获得OutOfMemoryError
因此,我会哄骗您..
检查上述链接的所有答案。
答案 2 :(得分:0)
用于管理Local file Path
Online url path
和BaseAdpter
lazy Loading
BaseAdpter
更有助于See
只需要关注ImageLoader imageLoader=new ImageLoader(context);
...
imageLoader.DisplayImage(url, imageView);
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