【发布时间】：2016-01-22 00:11:55
【问题描述】：
我有一个显示 ListView 的 android DialogFragment，每行包含一个标题和图像。一切正常，直到我使用 getDialog().getWindow().requestFeature(Window.FEATURE_NO_TITLE);
从 DialogFragment 中删除标题删除标题后，图像将停止显示在 ListView 中，所有显示的都是标题。 FEATURE_NO_TITLE 怎么可能影响 DialogFragment 中 ListView 的显示？从字面上看，没有其他代码行发生变化 - 只是那一行，并且图像停止显示在 ListView 中。
对话框片段 OnCreate
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.pick_photo_dialog_fragment, container);
getDialog().getWindow().requestFeature(Window.FEATURE_NO_TITLE);
Button closeButton = (Button) view.findViewById(R.id.closeButton);
closeButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
dismiss();
}
});
listview = (ListView) view.findViewById(R.id.photosListView);
listadapter = new PhotoListAdapter(getActivity());
listview.setAdapter(listadapter);
listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> a, View v, int position, long id) {
//do stuff
}
});
return view;
}
片段的 XML 只包含一个 ListView 和一个 LinearLayout 内的按钮...
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="@color/dark_gray">
<ListView android:id="@+id/photosListView"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:clickable="false"
android:listSelector="@android:color/transparent"
android:cacheColorHint="@android:color/transparent"
/>
<Button android:id="@+id/closeButton"
android:layout_width="100dp"
android:layout_height="40dp"
android:layout_gravity="center"
android:text="Close"
android:textSize="20dp"
android:textStyle="bold"
android:textColor="@color/white"
android:typeface="sans"
android:background="@color/transparent"/>
</LinearLayout>
ListAdapter 相关类
int[] mResources = {R.drawable.basketball, R.drawable.bodyweight, R.drawable.boulder, R.drawable.boxing, R.drawable.cardio,
R.drawable.crossfit, R.drawable.olympic, R.drawable.racquet, R.drawable.run, R.drawable.spin, R.drawable.squash,
R.drawable.swim, R.drawable.volleyball, R.drawable.weight, R.drawable.yoga};
String[] pictureNames = {"basketball", "bodyweight", "boulder", "boxing", "cardio", "crossfit", "olympic", "racquet", "run",
"spin", "squash", "swim", "volleyball", "weight", "yoga"};
public PhotoListAdapter(Context context) {
mInflater = LayoutInflater.from(context);
mContext = context;
}
public int getCount() {
return mResources.length;
}
public Object getItem(int position) {
return pictureNames[position];
}
public long getItemId(int position) {
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = mInflater.inflate(R.layout.photo_list_row_view, null);
holder = new ViewHolder();
holder.activityNameTV = (TextView) convertView.findViewById(R.id.activityName);
holder.activityImageIV = (ImageView) convertView.findViewById(R.id.activityImage);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
task = new CreateClassSetImageTask(position, holder.activityNameTV, holder.activityImageIV);
task.execute();
return convertView;
}
static class ViewHolder {
TextView activityNameTV;
ImageView activityImageIV;
}
ListView 行的 XML
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/mainlayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<TextView android:id="@+id/activityName"
android:layout_width="110dp"
android:layout_height="wrap_content"
android:text=""
android:textSize="20dp"
android:textStyle="normal"
android:textColor="#FFFFFF"
android:typeface="sans"
android:layout_gravity="left|center_vertical"
/>
<ImageView android:id="@+id/activityImage"
android:layout_width="0dp"
android:layout_height="100dp"
android:layout_weight="1"
android:scaleType="centerInside"/>
</LinearLayout>
加载图像的异步任务
public class CreateClassSetImageTask extends AsyncTask<Void, Void, Bitmap> {
WeakReference<ImageView> imageViewReference;
WeakReference<TextView> textViewReference;
int pictureNum;
public CreateClassSetImageTask(int pictureNumIn, TextView activityNameTVIn, ImageView activityIVIn) {
pictureNum = pictureNumIn;
imageViewReference = new WeakReference<ImageView>(activityIVIn);
textViewReference = new WeakReference<TextView>(activityNameTVIn);
}
@Override
protected void onPreExecute() {
}
@Override
protected void onPostExecute(Bitmap resultBitmap) {
if (imageViewReference != null && resultBitmap != null && textViewReference != null) {
final ImageView imageView = imageViewReference.get();
if (imageView != null) {
imageView.setImageBitmap(resultBitmap);
}
final TextView textView = textViewReference.get();
if (textView != null){
textView.setText(pictureNames[pictureNum]);
}
}
}
@Override
protected Bitmap doInBackground(Void... params) {
return decodeSampledBitmapFromResource(mContext.getResources(), mResources[pictureNum], 100, 100);
}
}
public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId,
int reqWidth, int reqHeight) {
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeResource(res, resId, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeResource(res, resId, options);
}
public static int calculateInSampleSize(
BitmapFactory.Options options, int reqWidth, int reqHeight) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
final int halfHeight = height / 2;
final int halfWidth = width / 2;
// Calculate the largest inSampleSize value that is a power of 2 and keeps both
// height and width larger than the requested height and width.
while ((halfHeight / inSampleSize) > reqHeight
&& (halfWidth / inSampleSize) > reqWidth) {
inSampleSize *= 2;
}
}
return inSampleSize;
}
【问题讨论】：
-
我通常将 requestFeature 指令放在 onResume 中。在 onCreateView 中它似乎不起作用（即使我从未遇到过您的问题）。如果您尝试这样做会发生什么？
-
@thetonrifles 谢谢你的想法——我试过了，但它抛出了一个运行时异常“在添加内容之前必须调用requestFeature()”——因为onCreateView（或者即使我切换到使用onCreate）总是得到在 onResume 之前调用，我不确定如何解决这个问题 - 必须在到达 onResume 之前添加内容，这意味着我不能在 onResume 中调用 requestFeature()。你如何让 requestFeature() 在 onResume 中工作？不管怎样，我不确定这就是问题所在——当我调用它时，它会起作用——标题消失了。它只会破坏片段的其余部分......
-
对不起我的错误。我对背景和宽度/高度定义感到困惑。尝试在 onCreateDialog 方法中添加 requestFeature。
-
@thetonrifles 也不走运
-
嗯好的...我正在尝试实现您的相同对话框来检查行为。我有一些问题。在适配器中，我看到您在 getCount 中使用 mResources，在 getItem 中使用 pictureNames。这些数组之间有什么区别？我还看到您正在使用 AsyncTask 来加载要显示的图片。可以分享一下它的实现吗？
标签： android listview android-fragments android-dialogfragment