在我的应用程序中,一个活动包含厨房,它可以在SD卡创建的文件夹中调用存储所有图像的顺序(saved_images),每件事情都可以正常运行,但是如果删除文件夹(saved_images),然后再次打开应用程序并保存任何图像,应用程序将再次创建(saved_images)文件夹,但保存的图像编号仍然记住SharedPreferences值并将图像存储在继续no。以前保存删除旧文件夹中的图片,我的目标是获得如下:再次保存,清除并保存SharedPreferences
一次从SD卡中删除(saved_images)文件夹自动SharedPreferences必须cleard如果(saved_images)文件夹中创建它再次存储从图像开始意味着图像-1,图像-2等等。
我试着用这段代码清除SharedPreferences,但它不起作用,可能会导致只存储一张图片,只能称为image-1。
2-如果我保存同一图像两次它保存,但我需要保存一次只有一次,当试图再次保存它时必须给吐司:已保存。
这是一段代码,我用它来清除和恢复SharedPreferences:
View vi=convertView;
final ViewHolder holder;
if(convertView==null){
vi = inflater.inflate(R.layout.gallery_items, null);
holder=new ViewHolder();
holder.text=(TextView)vi.findViewById(R.id.textView1);
holder.image=(ImageView)vi.findViewById(R.id.image);
holder.button=(Button)vi.findViewById(R.id.button_save);
holder.button.setOnClickListener(new OnClickListener() {
private Bitmap bm;
public void onClick(View arg0) {
String root = Environment.getExternalStorageDirectory().toString();
File myDir = new File(root + "/saved_images");
if(!myDir.exists()){
myDir.mkdirs();
bm = BitmapFactory.decodeResource(mContext.getResources(), images[itemPos]);
holder.image.setImageBitmap(bm);
SharedPreferences savedNumber = mContext.getSharedPreferences(PREFS_NAME, 0);
int lastSavedNumber = savedNumber.getInt("lastsavednumber",0);
lastSavedNumber++;
String fname = "Image-"+lastSavedNumber+".png";
File file = new File (myDir, fname);
if (file.exists()) {file.delete(); }
try {
FileOutputStream out = new FileOutputStream(file);
bm.compress(Bitmap.CompressFormat.PNG, 100, out);
out.flush();
out.close(); }
catch (Exception e) {
e.printStackTrace(); }
SharedPreferences saveNumber = mContext.getApplicationContext
().getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editorset = saveNumber.edit();
editorset.putInt("lastsavednumber",lastSavedNumber);
editorset.commit();}
else if(!myDir.delete()){
SharedPreferences saveNumber1 = mContext.getApplicationContext
().getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = saveNumber1.edit();
editor.clear();
editor.commit();
Toast.makeText(mContext, "saved", Toast.LENGTH_SHORT). show();}}});
vi.setTag(holder);}
else holder=(ViewHolder)vi.getTag();
holder.text.setText(name[itemPos]);
final int stub_id=images[itemPos];
holder.image.setImageResource(stub_id);
return vi; }
,这原代码,做工精细,所有的图像存储在顺序
在SD卡文件夹。
View vi=convertView;
final ViewHolder holder;
if(convertView==null){
vi = inflater.inflate(R.layout.gallery_items, null);
holder=new ViewHolder();
holder.text=(TextView)vi.findViewById(R.id.textView1);
holder.image=(ImageView)vi.findViewById(R.id.image);
holder.button=(Button)vi.findViewById(R.id.button_save);
holder.button.setOnClickListener(new OnClickListener() {
private Bitmap bm;
private String PREFS_NAME;
public void onClick(View arg0) {
String root = Environment.getExternalStorageDirectory().toString();
File myDir = new File(root + "/saved_images");
if(!myDir.exists()){
myDir.mkdirs();}
bm = BitmapFactory.decodeResource(mContext.getResources(), images[itemPos]);
holder.image.setImageBitmap(bm);
SharedPreferences savedNumber = mContext.getSharedPreferences(PREFS_NAME, 0);
int lastSavedNumber = savedNumber.getInt("lastsavednumber",0);
lastSavedNumber++;
String fname = "Image-"+lastSavedNumber+".png";
File file = new File (myDir, fname);
if (file.exists()) {file.delete(); }
try {
FileOutputStream out = new FileOutputStream(file);
bm.compress(Bitmap.CompressFormat.PNG, 100, out);
out.flush();
out.close(); }
catch (Exception e) {
e.printStackTrace();
}
SharedPreferences saveNumber = mContext.getApplicationContext
().getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editorset = saveNumber.edit();
editorset.putInt("lastsavednumber",lastSavedNumber);
editorset.commit();
Toast.makeText(mContext, "saved", Toast.LENGTH_SHORT). show();}});
vi.setTag(holder);}
else holder=(ViewHolder)vi.getTag();
holder.text.setText(name[itemPos]);
final int stub_id=images[itemPos];
holder.image.setImageResource(stub_id);
return vi; }
我知道疗法是有些东西丢失或错误的方式应用,所以请任何帮助方面将会理解,谢谢。
@ android116你检查了我的答案... – GoCrazy 2013-04-22 10:34:19