我有一个活动，显示存储在SD卡上的图像列表，虽然正在工作，但却产生两种不良情况。
1）取消进度对话框后会有大约3秒的延迟。我想在进度对话框消失后立即显示图像。
2）长时间点击图片后，上下文操作栏显示的时间太长（~4秒）。
...
04-26 21:23:03.902 18438-18438/co.glurl.appoid D/dalvikvm﹕ GC_FOR_ALLOC freed 235K, 9% free 26140K/28604K, paused 21ms, total 21ms
04-26 21:23:04.702 18438-18438/co.glurl.appoid D/dalvikvm﹕ GC_FOR_ALLOC freed 21K, 9% free 26453K/28936K, paused 20ms, total 20ms
04-26 21:23:04.712 18438-18438/co.glurl.appoid I/dalvikvm-heap﹕ Grow heap (frag case) to 31.831MB for 4147216-byte allocation
04-26 21:23:04.782 18438-18438/co.glurl.appoid D/dalvikvm﹕ GC_FOR_ALLOC freed 17K, 8% free 30519K/32988K, paused 17ms, total 18ms
04-26 21:23:05.362 18438-18438/co.glurl.appoid I/Choreographer﹕ Skipped 301 frames! The application may be doing too much work on its main thread.
04-26 21:23:09.902 18438-18438/co.glurl.appoid D/dalvikvm﹕ GC_FOR_ALLOC freed 11106K, 35% free 24621K/37752K, paused 18ms, total 18ms
04-26 21:23:11.452 18438-18438/co.glurl.appoid D/dalvikvm﹕ GC_FOR_ALLOC freed 157K, 30% free 26459K/37752K, paused 18ms, total 18ms
04-26 21:23:12.072 18438-18438/co.glurl.appoid I/Choreographer﹕ Skipped 291 frames! The application may be doing too much work on its main thread.
代码：
public class PhotosGridViewActivity extends Activity {
private PhotosUtils utils;
private ArrayList<String> imagePaths = new ArrayList<String>();
private PhotosGridViewImageAdapter adapter;
private GridView gridView;
private int columnWidth;
private int items;
private ProgressDialog progressDialog;
private boolean setEditableMode = false;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.photos_grid_view);
//Initialize a LoadViewTask object and call the execute() method
new LoadViewTask().execute();
}
//To use the AsyncTask, it must be subclassed
private class LoadViewTask extends AsyncTask<Void, Integer, Void> {
//Before running code in the separate thread
@Override
protected void onPreExecute() {
//Create a new progress dialog
progressDialog = new ProgressDialog(PhotosGridViewActivity.this);
progressDialog.setMessage("Loading...");
progressDialog.show();
}
//The code to be executed in a background thread.
@Override
protected Void doInBackground(Void... params) {
// Initilizing Grid View
InitilizeGridLayout();
// loading all image paths from SD card
imagePaths = utils.getFilePaths();
// Gridview adapter
adapter = new PhotosGridViewImageAdapter(PhotosGridViewActivity.this, imagePaths,
columnWidth);
try {
//Get the current thread's token
synchronized (this) {
//Initialize an integer (that will act as a counter) to zero
int counter = 0;
//While the counter is smaller than four
while(counter <= 4) {
//Wait 850 milliseconds
this.wait(1000);
//Increment the counter
counter++;
//Set the current progress.
//This value is going to be passed to the onProgressUpdate() method.
publishProgress(counter*25);
}
}
} catch (InterruptedException e) {
e.printStackTrace();
}
return null;
}
//Update the progress
@Override
protected void onProgressUpdate(Integer... values) {
//set the current progress of the progress dialog
progressDialog.setProgress(values[0]);
}
//after executing the code in the thread
@Override
protected void onPostExecute(Void result){
//close the progress dialog
try {
progressDialog.dismiss();
//initialize the View
} catch (Exception e) {
e.printStackTrace();
}
// setting grid view adapter
gridView.setAdapter(adapter);
gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
gridView.getItemAtPosition(position);
Intent i = new Intent(PhotosGridViewActivity.this, PhotosScreenViewActivity.class);
i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP);
i.putExtra("position", position);
PhotosGridViewActivity.this.startActivity(i);
}
});
}
}
private void InitilizeGridLayout() {
utils = new PhotosUtils(PhotosGridViewActivity.this);
gridView = (GridView) findViewById(R.id.grid_view);
Resources r = getResources();
float padding = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
AppConstant.GRID_PADDING, r.getDisplayMetrics());
columnWidth = (int) ((utils.getScreenWidth() - ((AppConstant.NUM_OF_COLUMNS + 1) * padding)) / AppConstant.NUM_OF_COLUMNS);
gridView.setNumColumns(AppConstant.NUM_OF_COLUMNS);
gridView.setColumnWidth(columnWidth);
gridView.setStretchMode(GridView.NO_STRETCH);
gridView.setPadding((int) padding, (int) padding, (int) padding,
(int) padding);
gridView.setHorizontalSpacing((int) padding);
gridView.setVerticalSpacing((int) padding);
gridView.setChoiceMode(GridView.CHOICE_MODE_MULTIPLE_MODAL);
gridView.setMultiChoiceModeListener(new MultiChoiceModeListener());
}
public class MultiChoiceModeListener implements
GridView.MultiChoiceModeListener {
public boolean onCreateActionMode(ActionMode mode, Menu menu) {
mode.setTitle("Select Items");
mode.setSubtitle("One item selected");
return true;
}
public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
return true;
}
public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
return true;
}
public void onDestroyActionMode(ActionMode mode) {
}
public void onItemCheckedStateChanged(ActionMode mode, int position,
long id, boolean checked) {
int selectCount = gridView.getCheckedItemCount();
switch (selectCount) {
case 1:
mode.setSubtitle("One item selected");
break;
default:
mode.setSubtitle("" + selectCount + " items selected");
break;
}
}
}
}
出了什么问题？
答案 0 :(得分：0)
问题出在这里
while(counter <= 4) {
//Wait 1 second <-this means 5 seconds you will wait because it will be repeated 5 times
this.wait(1000); //edit this or remove it
//Increment the counter
counter++;
//Set the current progress.
//This value is going to be passed to the onProgressUpdate() method.
publishProgress(counter*25);
}
答案 1 :(得分：0)
好的......因为我在这里无法帮助，我用Google搜索并发现有必要异步加载我的getView（）。对于further引用。